Part II. Humpback Whale Journey: A Year in the Lives of Humpback Whales (A Scientifically Correct Fictional Story)


Humpback Whale Journey

A Year in the Lives of Humpback Whales

(A Scientifically Correct Fictional Story)


Table of Contents



A Year in the Lives of Humpback Whales

Chapter 1—Glacier Bay

Chapter 2—Ocean Voyage

Chapter 3—Tlingit Arrives At The Islands

Chapter 4—Koholā is Born

Chapter 5—A Meeting with Spinner Dolphins

Chapter 6—Songs of the Humpback Whale

Chapter 7—More Dolphin Encounters

Chapter 8—Leaving Hawaiian Waters

Chapter 9—Back in Northern Waters

Chapter 10—One Year Later—Continuing On

Gentle Giants


Appendix 1: The Evolution of Whales and a Brief History of the Life on Earth

Appendix 2: Guide to the Taxonomy of the Humpback Whale

Appendix 3: Adaptive Radiation and the Evolution of Cetaceans
Appendix 4: A Brief History of Whaling

Appendix 5: Timeline of Hawai‘i’s Whaling Era

List of Sources for Humpback Whale Journey: A Year in the Lives of Humpback Whales


 Tlingit and Koholā, the principal characters in the story that follows, are fictional. They are used to describe a typical year in the life of humpback whales. The scientific information presented in the book is factual, providing an accurate portrayal of the whales and their environment.
 Every winter about 5,000 humpback whales migrate to Hawaiian waters to mate and give birth. They come from Alaskan waters and the Bering Sea far to the north where they feed on a variety of small fish and the tiny shrimp-like creatures known as krill. The humpback migration may be more than 5,000 miles in length, making it the longest migration by any mammal.
 Humpbacks begin arriving in Hawaiian waters in late October. The first to arrive are the juveniles, followed by adult males and females, and then pregnant females who give birth in Hawaiian waters and may mate again. 
 Around April or May the whales head north again for the summer months. The last whales to leave Hawaiian waters are new mothers and young calves, and their journey back to Alaskan waters completes the migratory procession of another mating and birthing cycle. 


All whales, dolphins, and porpoises are members of the scientific order Cetacea. Cetaceans are carnivorous, aquatic, air-breathing mammals found in all of the world’s oceans. The word “cetacea” comes from the Latin “cetus,” which means whale.

The two main evolutionary lines of cetaceans are the baleen whales, including humpbacks, and the toothed whales, including dolphins and porpoises.


Humpback Whale

Megaptera Novaeangliae

Humpback whales are scientifically classified as a Megaptera novaeangliae, their genus and species names. Megaptera means “Big-winged,” in reference to the humpbacks’ exceptionally long front fins, called pectoral fins, which are the largest pectoral fins of any whale species. Novaeangliae refers to New England, where early whalers first pursued humpbacks.


Humpback Whale—Megaptera Novaeangliae
Kingdom: Animalia
Includes all animals.
Phylum: Chordata
Chordates have a precursor to a backbone.
Subphylum: Vertebrata
Vertebrates are animals with a backbone.
Class: Mammalia[i]
Mammals are warm-blooded vertebrates that nurse their young.
Order: Cetacea
Cetaceans are aquatic, air-breathing mammals, including all porpoises, dolphins, and whales.
Suborder: Mysticeti
The baleen whales are characterized by two blowhole openings, a symmetrically shaped skull, 
vestigial leg bones, and the use of baleen for feeding. 
Family: Balaenopteridae
Balaenopteridae have a streamlined body, dorsal fin, and ventral pleats. Feed by engulfing and filtering.
Genus: Megaptera
From the Greek “megas” meaning great, and “pteron” meaning wing, referring to the long pectoral fins.
Species: Novaeangliae
Refers to New England waters where humpbacks were once abundant.


A Year in the Lives of Humpback Whales

Chapter 1

Glacier Bay

A rumbling sound sweeps across the landscape like distant thunder, echoing off the steep mountains and over the Glacier Bay waters. The loud sound emanates from the end of the bay where the face of a glacier calves a giant iceberg into the water.

From deep in the sea, a 50-foot-long humpback whale rises up from the depths, arcing her dorsal fin above the surface and exhaling a column of mist into the chilled northern air. The whale scans the water for food as another chunk of the massive glacier breaks off and tumbles into the sea, creating more sounds that resonate through the water and over the surrounding hills. These are the ancestral lands of the Tlingit Indians, who called these sounds “white thunder.”

The whale releases a powerful blast of air, breathes in, and then dives below. The vapor of her breath hovers above the mirrored surface of the water in a fine mist that slowly dissipates, eventually leaving the northern air again perfectly still.

The entire Glacier Bay region is ringed by the sea and the steep peaks of the St. Elias and Alsek Mountain Ranges.[ii]

Glacier Bay

Two hundred years ago, Glacier Bay was beneath 4,000 feet of ice. The glaciers were retreating, however, and by 1794 they had receded retreated five miles up the bay, 48 miles up the bay by 1879, and 65 miles today.

The mountain ranges surrounding Glacier Bay include the 18,000-foot peaks of the Alsek Range and St. Elias Mountains to the north, and the Beartrack Mountains to the south.

To the east are the Takhinsha Mountains and the Chilkat range, and to the west the Fairweather Mountains, including 15,300 foot tall Mount Fairweather. The Glacier Bay region is accessible to humans by plane or boat.

[Map: Glacier Bay region mountains]

During each long winter, new layers of snow settle over the mountains. This snow never fully melts during the region’s short, cool summers, and year upon year the layers of precipitation accumulate. This has gone on for millennia in these northern ranges, and the layers of snow are now packed and frozen into dense and seemingly permanent glaciers that are actually rivers of ice slowly but surely moving down the deep valley slopes.

Where the exposed faces of ice meet the sea, huge icebergs periodically break off and fall into the ocean, producing an accompanying roar of sound, the white thunder of Tlingit myth. The sounds of these calving icebergs are also recognized by the region’s humpback whales, including the whale we will call Tlingit, who breaches again and lets out a raucous blow as her body slams down onto the surface.

As if in response to these loud demonstrations, another whale breaches nearby. Tlingit continues to signal her own presence by slapping her tail fluke on the water’s surface. The vast icefields of this northern region formed long before the first humans arrived.

Today these ancient glaciers glisten in the sun, reflecting shades of intense blue. This is a place of elemental beauty. Large bergs drift through the crystal bay waters like castles of ice, frozen pieces of ancient time.

Searching for food, Tlingit swims to a depth of about 500 feet and then slowly rises toward the surface light. She has patrolled these waters off the coast of Alaska for the last six months, feasting on the summer bounty of marine life including the herring, krill, copepods, and plankton that fill the northern waters during summer and provide plenteous food for the whales.

Tidewater Glaciers

Thirteen of Glacier Bay’s 16 tidewater glaciers are actively calving bergs into the ocean. Such tidewater glaciers are found only in Alaska, Scandinavia and Chile.

The Glacier Bay region also contains over 100 alpine and valley glaciers. These are just some of Alaska’s 10,000 glaciers still holding on from the most recent ice age, which began 2.5 million years ago.

Tlingit spent most of the summer months north of Glacier Bay before she swam across the Gulf of Alaska and then down along the southeastern coast to Glacier Bay.


Glacier Bay is rare in that one may see there both advancing and retreating glaciers. Six are advancing and three are retreating, while the rest are mostly stable.

Advancing tidewater glaciers move over the land, erasing all life in their path before eventually calving into the ocean. A retreating glacier moves back up the mountains revealing the land underneath.

Glaciers often advance slowly over many years, but then sometimes they move suddenly and rapidly, scraping away the land and leveling whole forests. Advancing glaciers may surge downward up to 300 feet in a single day. This may be caused by earthquakes, melting patterns, or simply by the dynamics of the glacier’s formation on the mountainside.

When a large piece of a glacier falls into the ocean, a local tsunami may be generated. One of these localized tsunamis in Alaska sent water 1,700 feet up an adjacent hillside.

As glaciers retreat along Glacier Bay’s shores, the temperate rainforest slowly returns through a natural process of succession. First come the lichens, then moss and algae, then dryas and fireweed, until eventually the trees take over - predominantly willows, alder and spruce — until finally the glacier-torn lands are again reclaimed by the forest.

Navigating by instinct, Tlingit swam up the length of Glacier Bay until she reached the landlocked end of the bay, about 65 miles up from the mouth. Here at the terminus of the bay near the calving glaciers Tlingit makes one last search for feeding opportunities.

The isolated inlet is surrounded by mountain ranges rising up steeply from the azure waters of Glacier Bay. Temperate rainforest cover the lower slopes surrounding the bay, and encircling these sprawling woodlands are higher peaks all capped with snow.

Swimming unhurriedly through the bay waters, Tlingit rises to the surface and then turns on her side, lifting one of her pectoral fins into the air. The elongated fins possess a well-developed tactile (touch) sense, and are almost one-third of the length of her 50-foot-long body.

Tlingit pauses now at the surface and takes several breaths, each explosive exhalation producing a tall, white spout of mist. After sending up one last spray of air and water, Tlingit fills her lungs as full as possible and dives again into the dim ocean light.

Nearly twenty minutes later she reemerges, her back barely rising above the water as the air of her massive lungs is again propelled out through her blowholes, emitting a low, sonorous tone. Tlingit then draws in another giant breath and slips beneath the water.


[Diagram: Humpback blowholes]

Humpbacks have two blowholes, or nares, as do all baleen whales. Baleen whales are classified as mysticetes. Toothed whale species are classified as odontocetes, and have only one blowhole. All dolphins and porpoises are odontocetes.

The humpbacks’ blowholes are well-positioned so the whale barely needs to arch its back above the surface to breathe, and can easily breathe while continuing to swim forward. Humpbacks open and close their nares voluntarily, and they are able to control their blowholes as dexterously as humans are able to move their lips.


Far in the distance, a triangular dorsal fin ten feet tall slices the surface of the bay and then disappears with barely a riffle. To Tlingit, it is just a distant speck on the horizon, but she is instantly aware of what she seesonly one animal has such a tall dorsal fin: the orca, or killer whale, a predator of the humpback. Tlingit also has a dorsal fin, but the humpback’s dorsal fin is only about one foot tall, much smaller than the orca’s.

Tlingit is attuned to the high-pitched acoustic signals that confirm the orca’s presence. Conscious of the prospect of danger, Tlingit steers clear of the potential predator. She could probably out-swim or out-dive the orca if necessary, although Tlingit’s great size makes her generally less mobile than the orca.

In a direct confrontation, Tlingit could ram the orca with her huge head, or rostrum, but more likely, she would use her muscular tail region, called the caudal peduncle, to ward off the killer whale with powerful slapping blows.

The humpback’s caudal peduncle is the most powerful muscle in all the animal kingdom, and it is Tlingit’s best protection and ultimate defense, particularly since humpback whales have no teeth.

Today there will be no violent encounter between the two whales because the orca knows better than to challenge a healthy, adult humpback. Tlingit also avoids a direct confrontation by staying her course, and increasing the distance between herself and this

These are the misty days of fall when fog creeps up the hillsides and the land is barely visible. Clouds of sea mist drape the inlets, forming and dissolving above the Glacier Bay water. Suddenly a rumbling noise sounds throughout the bay, and it is unlike the deep thunderous booming of a calving glacier.

When Tlingit surfaces she sees a large ship approaching, and the people on the ship see the humpback whales. Tlingit’s huge spout of misty air causes shouts to come from the people on the boat’s upper deck.

Tlingit sends her whole body up into the air with two strong strokes of her tail, and she spins half way around in midair before crashing loudly back onto the water. This creates a huge splash to the delight of the onlookers dazzled by the magical moment, a close encounter with a breaching humpback whale.

Some of the whale-watchers are briefly frightened as the 45-ton humpback then swims directly toward them on a collision course with the boat. Not a moment too soon the giant creature slides beneath the surface and disappears.

In the medium of water, Tlingit’s enormous body moves with a lightness and apparent ease that makes her seem almost weightless.


Humpback Behaviors—Why Whales Breach

Humpback whales engage in many different behaviors that are categorized and analyzed by researchers. They roll, lunge, breach, mill around, and often slap the surface with their pectoral fins or tail flukes. Humpbacks also “spy hop,” poking their heads straight up out of the water, and male humpbacks sing long, complex songs, often with their head down and their tail near the surface.

Perhaps the most notable humpback behavior is breaching—no other whale species breaches more often than humpbacks. Breaching may be done by whales to gain a view of their surroundings above the surface, to loosen attached barnacles or parasites, or to send acoustic signals through the water to other whales in the area.

Breaching may also be used by the whales to intimidate or deter a predator, or to demonstrate fitness to other humpbacks during the mating season, and thus attract mates.

Young whales are often seen breaching over and over again as they practice their skills in imitation of adults. Also, we cannot discount the possibility that humpbacks breach simply because they enjoy doing itin other words, because it is fun!

Numerous hypotheses are put forward about why particular humpback behaviors occur. Voluminous amounts of data are gathered and studied, yet in the end the conclusions are often partial and uncertain, leaving much to be determined.

Humpback Whale Behaviors

Ø BlowEmitting air from the nares (blowholes) and sending up a spout of misty air and water.

Ø BreachLeaping from the water, the whale usually spins around 180 degrees and then lands on its back.

Ø Fluke Up Dive—Lifting the tail fluke up out of the water in an upward arch and then rolling the tail underwater while diving down. Also called Fluking.

Ø Head LungeLunging forward with the head out of the water; may be done during competitive situations. Also called Head Rise.

Ø Head Slap—Slapping the lower jaw onto the water’s surface.

Ø Pec Slap—Slapping one or both pectoral fins down onto the surface, possibly as a means of communication.

Ø Peduncle Slap—Lifting up the back half of the body (the peduncle) and slapping it down onto the surface.

Ø Round Out, or Peduncle Arch—Arching the back above the surface and then raising the tail fluke and diving below. This behavior led to the name “humpback.”

Ø Spy Hop—Rising the head straight up out of the water, as if to look around.

Ø Spouting—Sending up sprays of mist (from the blowholes) while breathing at the water’s surface.

Ø Singing—Emitting patterned sounds.

Ø Tail Slap—Slapping just the tail fluke down onto the surface; may be done repeatedly as a warning.


Tlingit’s speed averages about five miles per hour as she maintains a leisurely pace through the bay waters, zigzagging along and coming up for air about every eight minutes. She comes across some schools of herring in Glacier Bay, but they are only sparsely concentrated and hardly worth the effort required to capture them. These are Tlingit’s last days in northern seas.

Loons call out in the coves as crows and ravens let loose with their own distinctive sounds. Eagles soar high overhead, and onshore are remnants of the vast northern forests, the ancient home of the native people who plied these waters in dugout canoes fashioned from the region’s giant trees. The woodlands stretch on uninterrupted for miles, supporting a cornucopia of wildlife.

Many trees in these undisturbed, old growth forests have reached the end of their lives and now lay across the forest floor like fallen giants, slowly decomposing back into the soil to nourish new life. Dense conifer forests filter the rainwater that fills myriad streams that all eventually find their way to the ocean. Salmonberry lines the shoreline along with the golden fall cottonwoods.

During the northern summer the waters of the Inside Passage are teeming with salmon, shrimp, herring, crab, steelhead, grayling, sea urchins, rainbow and cutthroat trout, and many other species. Summer is over now, and the abundance of life has diminished. Tlingit uses more energy than she gains as she searches the water for edible life.

On this late November day Tlingit senses a changeperhaps it is the shift in the water or wind currents, or the end of the great plankton blooms. Tlingit interprets these changes as a directive to leave these waters.

It may be the migrating movements of other species, the air and sea growing cooler, or more subtle clues that cause Tlingit to begin her annual journey south. This is the end of summer, and time for the beginning of Tlingit’s long migration to tropical seas.

Tlingit has spent every summer of her 28 years of life feeding in the northern waters of the Pacific Ocean. Tlingit will now once again journey southward to the shallow contour of warm water surrounding an archipelago (island group) in the middle of the Pacific Ocean. The archipelago is called the Hawaiian Islands, and is thousands of miles from the nearest continent.

Instincts encoded into Tlingit’s genes over the millions of years of her ancestors’ evolution now once again urge her to begin her migratory path from Alaskan to Hawaiian waters. Every winter of her life she has basked in Hawai‘i’s tropical seas, often mating there and giving birth.

In the last seven years Tlingit has given birth to four calves. Now pregnant once again, Tlingit will be among the last of the whales to leave the northern Pacific and swim to Hawaiian waters where once again she will give birth and then nurse her offspring. Tlingit can feel the young one inside of her now, and its subtle and sometimes sudden movements are quite familiar.


Humpback Population and Migration

The North Pacific humpback whale population totals more than 8,000 whales, and is increasing by up to 7% each year. About two-thirds of these humpback whales migrate to the Hawaiian Islands each winter.

The warm and relatively shallow bays around Hawai‘i are an ideal place for humpback whales to give birth to their young.

Humpback Birthing Areas

Other birthing areas of North Pacific humpbacks include waters off Taiwan, southeast of Japan, off the coast of Baja, California, near the Socorro and Revillagigedo Islands off Mexico, in Central American waters, and near Ryukyu, Bonin, and the Mariana Islands.

The pathways followed by humpbacks on their annual migrations are only generally known. For decades the whales defied attempts to track them with tags and satellites, and information about the species was gained primarily from photographs of humpback tail flukes collected in various locations and catalogued by researchers.

Scientists continue to compare and cross-check fluke photographs taken throughout Hawaiian and Alaskan waters and other areas where mating and feeding occur. Improved satellite tracking methods provide valuable data about humpback migrations, as do new techniques of genetic analysis and acoustic monitoring.

Southern Hemisphere Humpbacks
In the southern hemisphere, humpback whales respond to the extending ice edge that comes with the Antarctic autumn. The winter freezing of the Southern Ocean is the biggest seasonal climate change on the planet. 
By late February a thin skin of ice begins to form, and soon thereafter the southern end of the Earth becomes a frozen continent. 

By May the size of Antarctica is doubled, with some 20 million square miles covered thick with ice. Thousands of humpbacks spend the summer in Antarctic waters, but during winter they are far away, having migrated north to the tropical waters of the Great Barrier Reef.

In both hemispheres, humpbacks prefer relatively calm, shallow breeding and birthing waters, such as Hawai‘i’s protected bays that are less than 600 feet deep and are around 75 degrees Fahrenheit.


Humpback whales have migrated between polar and tropical seas for millions of years, and Tlingit knows instinctively how to repeat this journey she has made every year of her life. She feels now the urgency of these last days of feeding and pursues every available food source, yet she finds little to eat so late in the season.

Raising her tail fluke above the water, Tlingit slams it down repeatedly, each time sending up a raucous splash. Finally, as if to say goodbye, she dips her giant head below and with one powerful thrust of her tail fluke propels her great mass down into the sea.

Tlingit suddenly feels something biting into her outer flesh. It is just a cookie-cutter shark (Isitius brasiliensis), and so small it is hardly an irritation to the giant whale. With its suction-cup lips, the shark grabs hold of Tlingit’s side and then sinks its teeth into her skin and blubber and waits.

As Tlingit swims she creates a water current that flows over the cookie-cutter shark, turning the fish’s body and driving its teeth deeper into Tlingit’s skin. Eventually the tiny shark extracts a two-inch circle of flesh from the whale, creating a small, scoop-like incision that the massive humpback barely feels. Tlingit bears many tiny scars from these little sharks as well as from her encounters with other marine creatures.

Now surfacing, Tlingit shoots up a spray of mist at full power. The air is powered by her huge lungs, and comes out of her blowholes at more than 200 miles per hour.


Humpback Whale Breathing

With each exhalation a humpback whale expels 90% of the air in its lungs. In comparison, a human only expels about 25% of his/her lung capacity. A complete humpback exhalation takes about ½-second, and an inhalation takes about one second.

Breathing requires significantly more energy in cetaceans than in land mammals, in part because water is about 900 times denser than air. Density is a measure of the mass of a substance in a given volume (e.g., pounds per square inch).

Whales are conscious breathers, choosing when to breathe and doing it with intention, unlike humans, who breathe reflexively in response to the level of carbon dioxide in the blood.

As Tlingit sets off across the vast sea to Hawai‘i, she is fortunate enough to come across one last school of herring. The fish are alerted by the movements of Tlingit’s giant form approaching, and within seconds they assemble into a single synchronous group moving as if they were one organism. The fish dodge and dart through the water in an attempt to escape the massive predator.

Tlingit swims below the school of herring and then circles around in a wide arc as she releases a thick stream of tiny air bubbles. Then she spirals inward and upward, carefully controlling her release of air as the miniscule bubbles rise to the surface. The spiral of air released by Tlingit forms a giant bubble net about 40 feet in diameter, encircling the fish and reining them in.

As the large school of herring is pushed closer together by the narrowing curtain of air bubbles, the fish quickly become confused. They are disoriented by the seemingly impenetrable barrier, and the ocean’s surface boils with all the trapped herring that are now crowded into a dense knot.

The summer sun is hot and bright, and shines brilliantly off the flanks of the leaping fish. Above this whole scene, opportunistic seabirds are drawn to the chaos of sound and movement, and they swoop down to catch the fish in midair.

Tlingit didn’t herd these fish together to provide a feast for the seabirds, however. The fish are her prey also, and she is causing them to congregate for a very specific reasonshe is hungry.

Tlingit dives straight down beneath the roiling mass of herring and then quickly turns upward and gives her flukes two strong strokes that send her body racing up toward the surface. Then she opens her jaws as wide as they will go and plows directly up through the school of frenzied fish.

Tons of water are instantly taken into Tlingit’s enormous cetacean mouth along with thousands of herring. The mesh-like trap of Tlingit’s baleen keeps the fish in as rivers of water stream out the sides of her mouth and flood back into the sea. Tlingit’s head rises up and her jaws clap shut as her 45-ton body lunges forward and slaps down onto the water.

Tlingit has no teeth, only baleen hanging from her upper jaw. The brush-like plates of baleen are comprised of a rigid, fingernail-like material woven together into a strainer that filters the tiny fish and crustaceans from the sea. Tlingit’s tongue weighs nearly two tons, and she uses it to push the water through the fine-fringed baleen and out of her mouth.

As the contents of Tlingit’s mouth are strained through the bristly baleen, her tongue is already pulling the food back toward her throat, which only opens to about ten inches in diameter.

In great gulps Tlingit consumes thousands of the tiny prey as well as one unlucky bird that had swooped down to grab a leaping fish just as Tlingit came up through the school. The bird was caught up in the maelstrom and now resides in Tlingit’s stomach.

This latest meal brings Tlingit’s consumption for the day to nearly three thousand pounds of food. She’ll need this nourishment for her journey south since there will be little or no food in Hawaiian waters. These last additions to Tlingit’s fat layer are very important as she begins her journey because only her thick layer of blubber will provide sustenance during her migration to and from Hawaiian waters.

The seas around the Hawaiian Islands are relatively safe and protected, but lack any significant food supplies for humpbacks. The whales return to Alaskan waters in late spring after the northern ice retreats, when the immense schools of herring and blooms of tiny krill again flourish in the nutrient-rich northern waters.

This explosion of life forms during the summer will provide plenteous food for the whales and ensure the survival of the North Pacific humpback population.

Tlingit continues to move further away from land. Her ocean crossing has begun in earnest now, and she will not stop anywhere or diverge from her migratory path until she reaches tropical southern seas. Tlingit will swim virtually non-stop across the open waters of the Pacific Ocean until she reaches Hawaiian seas where she will once again give birth.

Tlingit will encounter many other marine species during her open ocean journey. With each degree of latitude nearer to the equator, the water surface temperature will become warmer and the species she encounters will be different.


Chapter 2

Ocean Voyage

During her southern migration and for the length of her stay in tropical seas, Tlingit’s fat layer will provide her not only with food but also with the water she needs to survive. This substantial fat layer will be Tlingit’s sole source of life, and also a storehouse of energy that will feed not just one whale but two.

The baby now in Tlingit’s womb already weighs about one ton. The whale was conceived eight months earlier in Hawaiian waters, just about one month after Tlingit gave birth from the previous year’s conception. That calf made it through the dangers of its infant year, and is now weaned and surviving independently.

Tlingit’s shape has changed considerably since she became pregnant. Her body is normally fusiform (torpedo-shaped), but now has become much wider in the middle, more bulbous and round. The tiny whale now in Tlingit’s womb grows each day to look more like the whale it will soon become. When Tlingit reaches Hawaiian waters her calf will be born and her body will return to its normal shape.

Since humpbacks have baleen instead of teeth, it may seem strange that the lower and upper jaw of the fetal whale in Tlingit’s womb holds rows of tiny teeth barely emerging from the gums.

These teeth are a remnant of the humpbacks’ ancestral past, and will be reabsorbed into the gums before the whale is born. An explanation for these teeth is found in the fossil record, which reveals that baleen whales evolved from toothed whales tens of millions of years ago.

At a certain stage of the development of a humpback whale, the DNA seems to suddenly activate the whale’s knowledge that it is a baleen species and not a toothed species, and the tiny teeth begin to reabsorb into the gums and baleen begins to form. All of this happens before the whale is born.


Humpback Evolution

The medium of water has been the prominent factor in the evolution of humpback whales. In the early days of the whales’ evolution, from about 60 million years ago to 40 million years ago, gradual changes from generation to generation allowed the whales’ land mammal ancestors to become increasingly aquatic.

Over millions of years, the whale ancestor’s body began to elongate and became streamlined. The forearms began to develop into pectoral fins, the back legs slowly disappeared, and the tail grew into a massive fluke. The fossil record supports the conclusion that these changes occurred as predicted by the theory of evolution, which is based on the concept of natural selection, and is concerned with a species’ traits, the specific and sometimes unique physical and behavioral characteristics of individual members of the species.

Natural selection describes the process by which species change over time. Changes in a species occur because individuals with traits beneficial to survival in a given environment tend to produce more offspring than other members of the same species not possessing the particular trait. As more and more members possess the desirable traits, the species as a whole changes.

For example, if a broader tail assists an animal in getting food, the animals of the group with the broadest tails will be the best fed and thus stronger, and so will likely produce more babies. These babies are likely to possess the beneficial trait (e.g., a broad tail), since they are offspring of parents with the beneficial trait. The members of the population without the beneficial trait will be at a disadvantage and, on average, will get less food and have less offspring.

Through this natural selection process, broader tails eventually become more common among the surviving population of the species. In this way the species as a whole changes, or evolves over time.

The natural selection process directs which traits persist or disappear in a species, how the species changes over time, and ultimately, which species survive on Earth.


Size of the Humpback Whale

Female humpbacks are on average 45 feet long, while male humpbacks are about three feet shorter. Humpbacks are the fifth largest whale species. The largest documented humpback whale was an 88-foot humpback caught in the Caribbean by a whaling ship.

Blue whales are the largest of all whales, measuring about 100-feet long on average. The biggest blue whale ever recorded measured 190 feet, which is bigger than the biggest of the ancient dinosaurs.


Tlingit is far from any land, and she is guided by the currents of the sea as well as the movements of the sun and moon across the sky. Suddenly Tlingit sees an elephant seal, the largest of all seal species. This particular male elephant seal weighs nearly four tons and is nearly 18 feet long. Tlingit has seen this type of seal before, in past years in these open ocean waters.

When the elephant seal submerges and begins to sink, Tlingit also swims below. Together the two ocean creatures slowly drop deeper and deeper until they are about 500 feet down.

As Tlingit descends into the ocean depths her lungs are compressed by the extreme pressure of the water. The air in Tlingit’s lungs is forced into her nasal passages and the surrounding air sacs, and as she swims deeper the oxygen is stored in her blood.

Tlingit turns and heads back toward the surface, but the seal continues its descent into the dark abyss1,000, 2,000, 3,000, 4,000, 5,000 feet deep!

Tlingit, however, cannot see or visit the depths of this ocean where the seal now feeds. Eventually the elephant seal will make its way to a rookery on a California beach where elephant seals arrive each year to mate and give birth.

Elephant Seals

The elephant seal has evolved certain abilities that allow it to deal with the enormous pressures of the deep ocean. This is necessary for the seal to be able to search for the food sources that have helped the species survive.

Seals are mammals, as are humans and whales, and all mammals share numerous physiological characteristics. They are also very different. Elephant seals may sink into the ocean depths, while a human would quickly die from any deep submersion.

If a human were to descend in a similar manner as an elephant seal, the human would quickly succumb to nitrogen narcosis and death.

Elephant seals are a mystery in their ability to resubmerge with very little rest between dives. Most other deep-diving creatures, such as sperm whales, spend time resting at the water’s surface between dives, but some elephant seals engage in continuous diving, descending and ascending 24 hours a day for up to eight months.

Many seals regularly come ashore to sleep, but it’s believed that elephant seals may go a long time without sleeping. Sea lions are the only seals that even approach the sleepless feats of elephant seals, as sea lions may go three days diving and resurfacing before coming ashore for a rest.

Scientists are investigating whether deep-diving elephant seals may be catching some sleep as they sink into the inky black depths, or if sleep may simply be a trait evolved in land mammals to conserve energy. Perhaps elephant seals do not need to conserve energy due to the nature of their environment and their feeding habits. In other words, they may not need to sleep.

Elephant seals may dive more than one mile deep in just 20 minutes. At that depth the pressure of the water exceeds one ton per square inch, which is enough pressure to crush steel. As depth increases, pressure increases. At sea level, the pressure in the air is 14.7 pounds per square inch, and is known as one atmosphere of pressure.

One atmosphere of pressure is also defined as the weight of a one-inch-square column of air from the ground to 100,000 feet high. Water weighs about 800 times as much as air. In the ocean the pressure increases one atmosphere for every 33 feet of depth.

Humans can only go about 250 feet deep at most without specialized equipment. Ascending too rapidly will cause a human to get “the bends” as decompression sickness causes nitrogen to froth in the blood. The elephant seal, however, is able to withstand the extreme pressures of the deep ocean and then rise again fairly rapidly to the surface without harm.


Humpback Diving

The humpback whale’s capacity to hold oxygen in its muscle and blood allows the whale to dive more than 600 feet deep in the ocean and to stay under for significant lengths of time. During a deep dive, the whale’s lungs collapse under the extreme pressure and then expand again when the whale rises toward the surface.

Humpback whales have a substance in their bloodstream called myohemoglobin, which holds oxygen and delivers it to the body. The muscle tissue also has an oxygen-holding substance, called myoglobin, suffusing the tissue with large amounts of oxygen and making it deep red to purple in color.


For weeks Tlingit has maintained a steady pace across the ocean. She is now more than 2,000 miles from the protected waters of the Inside Passage, far from the glaciers and far from the land of bears, caribou, moose, and eagles. There are no longer any swarming blooms of krill or great schools of herring like those that recently satisfied her nearly insatiable appetite and provided the staples of her summer diet.

In Alaskan waters, Tlingit consumed as much as two tons of food per day. For the duration of her migration south, however, Tlingit will go without any significant food supply, and she won’t resume significant feeding until she returns to northern waters.

As Tlingit swims across the vast Pacific Ocean toward the Hawaiian Islands, the young one inside her continues to grow.


Earth’s Oceans

Two-thirds of Earth’s surface is covered by oceans, and these oceans are all interconnected. The Pacific Ocean is the deepest of Earth’s oceans, averaging about 13,000 feet deep.

The surface of the Pacific Ocean covers 25 percent more area than all of Earth’s entire land surface combined. If the surface of the Earth was smooth, then the whole planet would be some 12,000 deep under water. Because Earth’s terrain is so uneven the water on Earth fills the low areas and a vast amount of land remains above water.

The highest spot on Earth is Mt. Everest in the Himalayas, rising to 29,028 feet above sea level. The lowest spot is the western Pacific’s Marianas Trench, more than 37,000 feet below sea level.

Ocean water is a rich soup of many different substances, mostly hydrogen and oxygen, but also sodium, chlorine, magnesium, sulfur, calcium, potassium, bromine, carbon, strontium, boron, silicon, fluorine, and other elements.

Earth’s oceans include about 300 million cubic miles of water in all, which is more than 97 percent of all the water on Earth. Most of the other three percent of Earth’s water is locked in the polar icecaps.


Chapter 3

Tlingit Arrives At The Islands

Instinctively Tlingit interprets the ocean currents in a way that affects the path she chooses on her annual migration. These migratory instincts are dictated by rules of nature that change over time, including global weather patterns as well as water temperature variations in the North Pacific Ocean.

Now three weeks into her journey south, Tlingit begins to notice subtle differences in the sea and air, revealing that land is near. Finally after three weeks of traversing the vast expanse of the Pacific, the fathomless depths suddenly begin to have a bottom. Tlingit is nearing the waters where she was born, and now when she surfaces she sees land in the distance.

Tlingit finds her way each year back to these islands, the Hawaiian Islands, a group of relatively tiny specks of land in the middle of the enormous Pacific Ocean. Utilizing various navigational clues, Tlingit crosses the open ocean waters to find the archipelago of the Hawaiian Islands.

Many factors contribute to Tlingit’s ability to find the isolated Islands, including the position and movement of the sun and moon, and even the stars in the sky. Perhaps even the flights of birds provide clues, along with the winds that drive the ocean currents, the changing texture of the water, and the different look of the cloud formations in the distance.


Coriolis Force

A prominent feature of Earth’s weather is the prevailing wind patterns that circulate in large predictable ways due to the rotation of the Earth and the heat of the sun.

The Earth’s curvature also affects sunlight reception, which is different in the tropics than in the polar regions. This difference in sunlight also affects global wind patterns. Prevailing winds are deflected to the right by Earth’s spin, and this effect is called the Coriolis Force.


Finally Tlingit reaches the northern shore of the northernmost Hawaiian Island, the very waters where she was born. Off the coast of Kaua‘i, Tlingit swims past bays and peninsulas she has seen many times before during her winters in Hawaiian waters.

Tlingit recognizes the underwater reef that fringes the shoreline as well as the shallow inlets and the deeper bays. Finally she reaches the place that feels most familiar, the site of her own first days, Kaua’i’s Nāpali Coast.

The rugged shoreline of the Nāpali is like no other. Sheer lava cliffs rise thousands of feet straight up from the sea as waterfalls thunder down from the peaks. The mountains are topped with steep spires and long, fluted ridges separated by deep-carved valleys.

Streams cascade down from the high ramparts and tumble over the coastal cliffs before converging in the lower valleys and flowing into the ocean.

For hundreds of centuries the mountainous winter surf has pounded at this seacoast, and with each passing year a few more inches of coastline are lost to the sea. Some of the sea-cut chambers along the base of the Nāpali cliffs are large enough for Tlingit to swim into, but she simply registers the memory of these massive caverns and continues on her way.


Caves of Hawai‘i

The younger Hawaiian Islands to the southeast, especially Hawai‘i Island (also called The Big Island), have coastal caves formed by lava tubes. These lava tubes were created during volcanic eruptions and serve as conduits for streams of molten earth. Lava tubes usually form near the surface when the liquid lava drains out leaving the shell behind.

The caves of Kaua‘i’s Nāpali coast are different, however. They were formed when certain sections of hard lava fractured and then were subsequently filled by lava flows, forming dikes. Centuries of powerful surf then created caves by smashing the dikes’ relatively weaker and less dense surrounding rock.

Waves push water into the crevasses, resulting in extreme compressional forces scouring out caves from the zones of weakness all around the dikes. Eventually a cave’s ceiling may fall in, further increasing its size.


In past years, Tlingit has spent time in the waters all around the island of Kaua‘i, moving to different areas depending on the prevailing winds and weather. Compared to the long distance Tlingit migrated across the ocean, the distance around the island is relatively small.


The Hawaiian-Emperor Chain

The Hawaiian Island Chain extends in a line from the southeast to the northwest for about 1,523 miles, crossing through the Tropic of Cancer. At the southeast end of the chain are the eight main Hawaiian Islands, including Hawai‘i Island (the Big Island) located at 19 degrees north latitude.

At the northwest end of the Hawaiian Chain is Kure Island, located at 28.5 degrees north latitude. To the north of Kure is a chain of undersea volcanoes known as the Emperor Chain.

Together the Hawaiian Island Chain and the Emperor Chain comprise the 3,726-mile-long Hawaiian-Emperor Chain. Only the eight main Hawaiian Islands and the relatively tiny reefs, shoals and atolls of the Northwestern Hawaiian Islands rise above the water.


Northwestern Hawaiian Islands 

Combined Land Area: 6 square miles.

Size Comparison: One-tenth of one percent of Hawai‘i’s land area.

Also called: The Leeward Islands.

The eight main Hawaiian Islands comprise 99.9% of the total land area of the State of Hawai‘i. The Northwestern Hawaiian Islands constitute the other .1% (one-tenth of one percent) of the State of Hawai‘i’s land area.

The Northwestern Hawaiian Islands extend for about 1,200 miles to the west-northwest of Kaua‘i, and include 124 scattered islets, shoals, and atolls beginning at Nihoa, about 150 miles west-northwest of Kaua‘i. Most of the tiny islets of the Northwestern Hawaiian Islands barely rise above the water’s surface.

After Western contact, the Northwestern Hawaiian Islands were visited by various ships, including whalers, fishermen, coal transport ships, salvage ships, guano miners, collectors of bird eggs and feathers, and hunters of seals and turtles.

In 2000, a Coral Reef Ecosystem Reserve was declared on 99,500 square nautical miles northwest of the main Hawaiian Islands, including the previously designated Hawaiian Islands National Wildlife Refuge. The Reserve bans oil and gas drilling as well as dumping, and places new restrictions on fishing.

The Reserve contains about 70% of the United States’ coral reefs, and supports at least 7,000 species of fish, birds, marine mammals and other flora and fauna, about half of which are endemic (unique) to the Hawaiian Islands.


The Island of Kaua‘i

The island of Kaua‘i is more than five million years old, and rimmed with white-sand beaches and relatively flat lowlands that taper gently upward before rising steeply into the heartland’s volcanic summits.

The interior of the ancient island consists of the towering remnants of several extinct volcanoes, the most prominent being 5,148-foot-tall Mt. Wai‘ale‘ale, which once was thousands of feet taller than it is today. Surrounded by a wild river and canyon wilderness, Mt. Wai‘ale‘ale is considered the wettest spot on Earth.


Mt. Wai‘ale‘ale

Wai‘ale‘ale, means “Rippling water,” and refers to the lake that sits atop the plateau at the volcano’s summit where the Hanalei River begins. Located at the center of the island of Kaua‘i, Wai‘ale‘ale is said to be “the wettest spot on earth” due to the extreme amount of rainfall there, including 681 inches in 1982. Wai‘ale‘ale has an average annual rainfall of 451 inches, the highest in the world.

Wai‘ale‘ale’s actual rainfall may be even more than 451 inches because high winds at the summit are known to blow the rain horizontally over automated rain gauges that relay weather information via satellite.

The single rainiest year on record at Wai‘ale‘ale’s summit was in 1982, when 681 inches were recorded. India’s Cherrapunji Village received 905 inches of rainfall in 1861, but only has an average annual rainfall of about 428 inches.


Like a giant cup, Wai‘ale‘ale’s summit crater gathers water from the clouds and filters it downward into the island’s aquifers. The dense trees and shrubs in the highland crater comb the moisture from the sky and percolate it down through the igneous rock to the island’s porous lava interior.

The rainwater replenishes the mountain streams that flow out in all directions from the summit into the lower valleys.

Along the coast a small swell rolls in against the cliffs as waves tumble onto the white sands of each isolated beach. Between the green, furrowed fingers of the Nāpali sea cliffs are high, inaccessible valleys, and where the lower valleys meet the ocean the isolated coves give way to broad sandy beaches.

For three days the tradewinds have been blowing strong from the northeast, but now the winds have subsided. Bright clouds form and dissipate over the foothills and coastal cliffs where sprinkling rains scatter the sunlight and create rainbows that add even more color to the majestic land.

Tlingit feels an instinct that tells her she has reached the very waters where she was born, and all of her senses confirm this. Perhaps Tlingit’s magnetic sense also helps her recognize this place, just as it helped her travel thousands of miles to Hawaiian waters. The sea bottom beneath her has its own unique magnetic signature, imprinted in her memory at birth and now possibly again recognized by her in these native waters.


Humpbacks possess a magnetite substance in their brain, which makes attunement to Earth’s magnetic field possible. The whales are magnetoreceptive animals that have the ability to use their own internal compass to help determine direction, and this magnetic sense helps guide them in their navigations over the globe.

Earth’s magnetic field radiates up and out from the surface of the ground at every point on the planet. Humpbacks migrating to Hawai‘i may be aided by their recognition of consistent global changes in the magnetic field as it emanates up from the planet’s center and out from the Earth’s surface.


Animal Magnetoreception

Every latitude and longitude on Earth’s surface differs in the strength of its magnetic field, as well as the angle at which the magnetic field comes up from Earth’s surface.

Certain magnetoreceptive animals, many of them migratory species such as whales, have the ability to sense the subtle differences in these magnetic field strengths, as well as the angles at which the field emanates up from Earth’s surface. This assists the whale’s navigation process during its long migration.

While latitude and longitude qualities of Earth’s magnetic field are predictable over long distances, in some particular places there are sudden changes in the Earth’s crust that cause the strength of the magnetic field to vary significantly. These magnetic anomalies, or localized differences, may become familiar over time to magnetoreceptive animals.



Earth’s magnetic energy is generated by the planet’s molten iron core, and constantly rejuvenated by the planet’s spin. The Earth spins at a speed of 1,035 miles per hour to the east at the equator, so there is plenty of movement to keep the magnetic field strong. Earth also moves at 60,000 miles per hour in orbit around the sun.


To Tlingit, the land is a foreign place that her aquatic nature prevents her from visiting. In ancient times her ancestors walked on land, so perhaps somewhere deep in her genetic memory Tlingit retains a sense of this terrestrial past. Tlingit’s only connection to the land now is that she swims near the streams and rivers that are gradually returning the islands back to the sea.

During times of heavy rain, the ocean near the large rivermouths is clouded with suspended sediments carried down from the mountains, and this is noticed by the whales. All along the coast the red earth flows down from the highest volcanic peaks and into the sea in a process of erosion that began many millions of years ago, even before the island had finished forming.

Tradewinds blowing over the ocean gather up the moisture of the sea. As the winds reach land and rise up the mountain slopes the moist air cools and condenses into clouds that rain down upon the islands.

The tradewind showers slowly but persistently carry the land back into the ocean, and this is all part of a larger process of volcanoes growing up from the seafloor, rising above the surface to become islands, and then over millions of years slowly eroding back down beneath the waves.

With the experience Tlingit has gained during her 28 years of life, she instinctively knows what her ancestors have for centuries known, that these Nāpali waters are her home. This is where she was born and where her offspring were born, and where they will return each year of their lives.

Tlingit swims along the northern shore of the northernmost Hawaiian Island, basking in the warm, tropical waters that allow for the continuation of an eternal cycle.


Chapter 4

Koholā is Born A fiery sunset blazes across the western sky where cumulus clouds glow red as if lit from within. Slowly the colors blend into deeper tones and then dissolve into the darkness of night. Soon the eastern sky begins to radiate light and a silver moon emerges full and bright over the water.

The sea is as smooth as glass, its calm surface mirroring the moon and stars. Tlingit comes up for a breath and water pours off her back reflecting the heavens above. Her body shines with celestial light as she exhales a spray of phosphorescent mist into the still night air. Silently again she slides beneath the surface.

There in the shallow waters of a sheltered Nāpali cove, Tlingit brings into the world a baby humpback whale. Born into the watery moonlight the baby is nuzzled upward by her relieved mother and swims to the surface. We will call this whale Koholā, the Hawaiian word for whale.

Koholā is confused for a moment as she crosses the boundary between air and water. The newborn whale’s eyes are dazzled by the luminous sea as she takes her first breath.

Swimming below the surface, Koholā finds her mother’s teat and the milk begins to flow plentifully into the infant’s suckling mouth. For Koholā’s first year of life, the milk will provide her with all the nourishment she will need to grow.

Born twelve feet long and weighing two tons, Koholā will gain as much as 100 pounds per day and grow about one foot longer each month. Her light-colored skin will darken within days, but for now it is a silken color that perfectly matches the pearl moon above.

Morning arrives. The sun climbs above the mountains in the east and the moon is still visible on the western horizon. From opposite sides of the sky the two bright beacons welcome Koholā into the daytime world.

As the sun rises higher the moon disappears, and Koholā lingers at the water’s surface. She feels the warmth of the sunlight on her skin, and she is curious about this strange round object above beaming down golden light.

Though she is just an infant, Koholā naturally begins to utilize her innate abilities that help her make sense of her environment. Like all humpback whales, Koholā has the ability to see in air as well as underwater. Her cornea is like a bifocal lens, allowing efficient vision both above and below the water’s surface.

When Tlingit is underwater she looks through the more rounded portion of her eye’s cornea. When she is above the water, Tlingit rolls her eyes back a bit in order to look through the more flattened portion of the cornea, which has a narrower lens and is better able to focus light on her retina.

Koholā slowly becomes familiar with her dual vision ability, which allows her to focus her eyes in this strange other medium, this world above her underwater world. Perhaps it is not surprising that humpback whales have retained some adaptations to seeing in air, since their evolutionary ancestors lived on land. About 60 million years ago those mammalian land dwellers roamed the shores of the Tethys Sea.

The evolutionary connection spans even farther back through time, to some 370 million years ago when the whales’ ancestors lived in the sea. They crawled up from that primordial ocean to inhabit the land before eventually returning to the water. The evolutionary process has come full circle, from the water to the land to the water.



Between about 60 and 30 million years ago, the whale ancestors called mesonychids ventured into the oceans to search for food, and gradually became more aquatic. (See Appendix 4 for more details.)


Koholā’s responses in her new environment are guided by instincts passed down through the centuries from one generation to the next and now encoded in her genes.

She pauses now with her eyes just above the sea, reveling in her newfound ability to see above the ocean’s surface.

 For several weeks now the two whales have lingered near the stretch of coastline where Koholā was born. With each passing day the young one grows more accustomed to her surroundings in these warm Hawaiian seas, showing all the exuberance of a healthy calf as she comes to the surface and repeatedly slaps her pectoral fins down on the water.
 Many of Koholā’s antics are in imitation of her mother as well as other humpbacks she encounters nearby. Some of Koholā’s behaviors, however, are just curious experiments that express her interest in exploring the ocean world around her and her own developing abilities.
 As the whales move along the northern coast, the infant swims just in front and to the side of her mother’s dorsal fin, and above her pectoral fin. Pushed forward by the maternal current, Koholā is able to keep up with Tlingit’s fast pace, and the calf’s efforts are supplemented by Tlingit’s graceful power. The two whales move as one, with Koholā gliding effortlessly in the slipstream flow provided by her mother. 
 Quite naturally attuned to the water currents, Koholā swims below again and then rises to the surface where her mother uses a pectoral fin to push forward a sizeable wave of water that propels the baby forward. Koholā excitedly rides the rushing water, sliding down the wave’s face before veering off and circling back around again to be next to her mother.
 Koholā gets stronger each day, and more proficient at using her tail fluke, which is already extremely powerful. Soon Koholā discovers her ability to breach. With just a few strokes, her whole body comes flying out of the water. She is exhilarated by this breaching activity and repeatedly thrusts her tail fluke to send her body surging up from the sea, then turning over in midair before crashing down on her back with a splash. 
Koholā makes one particularly high breach and then swims excitedly toward Tlingit, circling her mother twice as if celebrating the new skill she has learned.
 Perhaps as a demonstration to her calf, Tlingit occasionally exhibits her own breaching ability, soaring up from the surface and then landing with a regal splash. Tlingit’s full breach makes a loud sound under the water as well as above, and just seconds later a similar sound is heard from another whale in the distance. 
 Communication with other whales is just one of the possible reasons for breaching, just as the sounds produced by breaching are just one of many ways whales communicate with each other. Koholā’s breach is still somewhat of a clumsy child’s attempt compared to her mother’s acrobatic pirouettes.

Tlingit has several ways of sensing her environment. Adorning the front of her lips and upper and lower jaw are numerous golf-ball-sized sensory nodules called tubercles.

Each of these fleshy bumps contains a single hair follicle called a vibrissa, which is a coarse bristle about one-inch long connected to sensory nerves. Tlingit’s vibrissae determine temperature, currents, and other information about her surroundings.

 Tlingit mills about as she watches Koholā frolic in the water. The work of birthing is done now and Tlingit enjoys the company of her new child and the relative safety of warm Hawaiian seas. Tlingit swims toward Koholā and allows the young one to nurse and gain the sustenance she needs to grow. 
 Tlingit produces over 100 gallons of milk per day, and this milk is comprised of nearly 50% fat. The milk provides ample nutrition for Koholā, who will double in length by her first birthday. The infant barely needs to suckle her mother as the milk is pushed out voluntarily by Tlingit with a pressure that sends it flowing into Koholā’s mouth. 
 Satiated for the moment, Koholā swims just below the surface and glides effortlessly through the sea’s prism of light. As each day passes, Koholā’s white skin is slowly darkening. Her body grows at a rapid pace, nourished solely by her mother’s milk. 


Chapter 5
A Meeting with Spinner Dolphins
Now fast approaching are five small spinner dolphins (Stella longirostris), known to Hawaiians as nai‘a. The dolphins are about four feet long and swimming straight for Tlingit. 
Speeding along at about 20 miles per hour, all five dolphins arch above and below the water in synchronous motion. About every 30 feet, the curves of their backs appear and then as quickly disappear again beneath the water.
 Two of the dolphins demonstrate why they are called spinners when they suddenly leap straight up out of the water, spinning and flipping head over tail before landing with a splash. As they approach Tlingit and Koholā, the dolphins group together again and swim in a wide arc around the pair of whales. 
 Sounds are streaming through the water as the dolphins bounce high frequency pulses off their fellow cetaceans and interpret the returning sound waves. In the distance more dolphins appear and join the pod.
All toothed cetaceans, including all dolphins, have the ability to send out pulses of high frequency sound. They bounce these sound pulses off objects, and then interpret the returning echoes. This use of sound pulses is known as echolocation, and allows marine mammals to “see” an acoustic image of their surroundings and also to communicate with other dolphins. 
Echolocation is used by dolphins to locate and identify fish and other prey. Echolocation pulses are also used to stun prey, making it easier to catch.
 Dolphins send out sound pulses through an area of their head known as the melon, a lens-shaped organ that extends from the rostrum, or beak, to the blowhole. The melon is filled with a fine, waxy oil held in suspension by web-like tissues. 
 Implosive movements of air through the dolphin’s nasal passages produce the echolocation. The sound waves are then focused through the melon and emitted through the forehead in a narrow stream of high frequency waves.

Dolphins are considered vocal learners, which means that they modify their vocalizations as a result of the vocalizations of other individuals (e.g., other dolphins). Many birds are capable of vocal learning, but it is thought to be rare among mammals.

Humans, harbor seals, and cetaceans are the most versatile vocal learners, readily able to imitate and use new sounds for communication. Pods or extended families of dolphins and whales may develop their own distinct dialects of echolocation.

Some nonhuman primates have been conditioned to alter the amplitude and duration of their vocalizations, but the only other mammals known so far to be able to change the frequency parameters of their vocalizations are Greater Horseshoe bats, which learn the main frequency of their echolocations from their mother.
 Tlingit and Koholā are now surrounded by dolphins, more than 20 of them. Some jump up repeatedly while others swim just beneath the surface with only their dorsal fins showing. Two of the dolphins leap skyward in perfect unison as if in a choreographed dance. 
 One dolphin jumps higher than all the rest, twirling through the bright sunlight as it flashes off her wet skin. Two other dolphins swim around the whales in a wide circle, the dolphins’ backs and dorsal fins slicing up through the water and then disappearing.
 These coastal spinner dolphins now encircling Tlingit and Koholā are quite different than the open ocean dolphin pods that live far from shore and follow pelagic (deep-water), schools of tuna. The coastal pods of spinners never venture too far from the Islands, and seeing them reassures Tlingit that she is in her home waters. 
 All around Tlingit and Koholā the water is filled with high frequency echolocation pulses resounding off the humpback whales and enveloping their bodies. The whole experience feels new to Koholā, although she has felt these particular sound vibrations before.
 Koholā’s mother encountered these same spinner dolphins just before Koholā was born, and they echolocated Tlingit with high frequency sounds. This awakened Koholā in the womb as the pulses sounded out her form and likely revealed to the dolphins that inside of Tlingit there was another whale soon to be born. 
 Tlingit is familiar with the sounds of the dolphins that now surround her. The presence of this pod extends back centuries in these northern Kaua‘i waters, and Tlingit has encountered these particular dolphins many times before. In the echolocation pulses that now penetrate her skin, Tlingit recognizes the pod’s signature sounds. 
 Playful and curious, the spinner dolphins send out a chorus of pulses that fill the water with high frequency sounds. One of the dolphins swims near to Koholā and examines her using echolocation. Seventy pulses each second bounce off Koholā and reflect back to the dolphin, revealing information about the young whale.
 When she feels the sound vibrations on her body, Koholā instinctively swims near her mother who swims on unconcerned. Koholā soon decides that these visitors are not threatening, and she briefly follows after the dolphins.
 For Tlingit a certain comfort comes from seeing these nearshore dolphins and hearing their echolocation pulses that fill the water with sounds and remind her of years past in tropical waters. The dolphins continue on their way and Tlingit uses her huge tail fluke to generate speed and catapult her body into the air.
 As if in response to Tlingit’s breach, a spinner dolphin zooms out ahead and repeatedly flies up with exuberant spins and gyrations. Each splashdown sends up a misty spray that catches the sunlight and divides it into a rainbow of colors that quickly dissipate in the ocean breeze. 
 The skills that Koholā learns during her first year of life will help her make the transition to self-sufficiency. Humpbacks are carnivores, and though their prey is small, capturing it still requires the strategies of a predator. Young humpbacks learn these skills from older whales, and the old continue to learn from experience, always adapting and refining their ability to hunt for food.
 Koholā will be trained by her mother in the skills she will need to survive. Eventually she will no longer be dependent upon her mother’s milk and her mother’s protection. Koholā may eat some small fish or euphausiids (krill) during her first summer in Alaskan waters, but she will also continue to nurse.
 When Koholā is about ten months old, she will be weaned and will no longer rely on her mother’s milk for sustenance. Koholā’s survival will then require that she learn to catch an adequate amount of food each day to sustain her rapidly growing body. 
Seasonal Behaviors
Humpback whales, like all other mammals, instinctively follow complex social and biological rules that help the species survive. Humpbacks feed and increase their size and strength during summer in northern waters in preparation for the next migration south. Food supplies in Alaskan waters dictate humpback distribution as well as social interaction among the whales.
Reproductive processes determine when the whales arrive in Hawaiian waters their distribution around the Islands during the winter months and when they leave for Alaskan seas. 
The annual migration of humpbacks to Hawaiian waters occurs not all at once, but in a long parade of whales arranged according to their reproductive status. The first humpbacks to begin their southward migration are the previous year’s mothers along with their calves, who will be weaned during the winter in Hawai‘i. Then the subadult whales begin their journey, followed by mature whales.
The last humpback whales to head south are expectant mothers, who stay in the food-rich northern ocean as long as possible. Finally they too head for tropical seas where feeding opportunities are scarce and all facets of the whales’ lives are affected by the desire to mate, give birth, and raise young. 
Integral to the humpback mating process are the whales’ songs, which are elaborate and operatic vocalizations that permeate Hawaiian waters during winter.


Tlingit has overcome great odds in her lifetime, and her body bears many marks inflicted upon her by other ocean creatures. Tlingit’s 15-foot-wide tail fluke is scarred from an attack by a killer whale (Ornicas orca) and her left pectoral fin is missing a small piece due to a tiger shark (Galeocerdo cuvieri). Her body also has numerous smaller scars and markings from various encounters with other ocean life.

A large area of Tlingit’s back is colored by the presence of countless diatoms, the one-celled algae that live in northern waters. Algae growth had tinted the lighter patches of Tlingit’s skin yellowish-green, but these colors have mostly faded since she returned to Hawaiian waters.

Tlingit’s body also bears many small, circular, white marks created by several types of barnacles that were attached to her skin in northern waters. Since Tlingit arrived in Hawaiian waters most of the barnacles have fallen off, leaving only the white rings of scar tissue.

Tlingit is among the last of the North Pacific humpbacks to arrive in the tropics. In Alaskan waters she ate up to two tons of food per day, and she stored the energy she needed for her long journey and for the rigors of birthing and nursing. Now she basks in warm but nutrition-poor tropical seas.

More than 1,000 pounds of barnacles may be attached to a humpback whale’s skin in Alaskan waters. The most common barnacles attached to humpbacks are acorn barnacles (Cornula diaderma, and Coronula reginae), and long-necked goose barnacles (Conchorderma auritum).

Some barnacle species are endemic (unique) to particular species of whales, meaning they grow only on that species and are found on no other whales. These endemic barnacle species favor certain whales due the particular chemical make-up of the secretions on the whales’ skin.


 Instinctively Tlingit knows the rhythms of this ocean. She senses the daily pulse of the tides and is familiar with the storm-driven swells that arrive from the North Pacific Ocean. Tlingit easily navigates the currents along the island shorelines as well as the deep-water currents that move in seasonal and semi-predictable ways. 
 Today a winter swell pulses energy through the sea and sends waves toward Hawaiian shores. Big winter storms spawned near the humpbacks’ Alaskan feeding grounds now move over polar seas thousands of miles from the Hawaiian Islands. 
The energy of these massive weather systems radiates through the whole ocean as the storms progress northwest across the top of Earth. Today powerful ocean waves buffet the northern coastlines of all the Hawaiian Islands. 
A wave’s period is determined by the time it takes for one complete wave to pass a stationary point. To surfers, anything above a 12-second period wave constitutes a “swell,” and usually means the beaches have great waves for surfing. 
Wave height is measured from the peak to the trough, and may exceed 50 feet on the outer reefs during the biggest of swells. Large waves are sent toward the Hawaiian Islands by low pressure storm systems that form hundreds and even thousands of miles from Hawai‘i.
 A wave’s wave period is the time it takes one complete wave to pass a given point. The longer the wave’s period, the bigger the height and power of the wave. A big swell generated in Alaska may produce a swell that arrives in Hawai‘i days later with a period of up to 25 seconds between each wave.
 On Kaua‘i’s northern shore, great upwelling mountains of water appear on the horizon and then roll in with a thunder from the open sea. The waves slowly take form as they surge toward land, each peak rising and curling over into a white explosion of foam and spray. Each time Tlingit surfaces to breathe, she sees the billowing mass of the giant, breaking waves.
 Every point and bay is alive with crashing waves as the energy of the ocean releases itself upon the island beaches. Tlingit and Koholā linger near the outer reefs not far from where giant waves are breaking. Tlingit has swam near such large ocean waves many times before in northern as well as southern waters. 
 The wind is calm, and a salty mist lingers over the foothills where clouds hang low. Intermittent sunlight shines down golden light on the land and water, and a cool vapor rises from the sea and drifts over the coastal mountains. Offshore a double-hulled canoe sails totally silent, pushed by an almost imperceptible breeze. The six-person crew occasionally paddles as they gaze in quiet appreciation at the majestic beauty of the Nāpali coastline. 
 Recently the rains have been plentiful over the island mountains and the rivers are flowing full. Near the seacoast, where the land drops away sharply, the high ridges are lined with waterfalls that plunge down each pali (cliff). Steep pinnacles and tall spires stand sentinel over the valleys like sacred monuments. The vertical green faces are lined with silver streams that reflect the sun like ribbons of light.
 Sculpted by centuries of rains, the Nāpali mountains on Kaua‘i’s northern coast have been honed into sheer cliffs and razored ridges. Amidst the monumental seacliffs are pockets of higher land that allow no gradual path to the ocean, sending the streams plunging down steep descents into deep pools that calm the tumultuous flow. The myriad streams of the upper valleys converge into thunderous watercourses that cascade over tumbled boulders before finally finding their way to the sea.
 For thousands of centuries this Nāpali coastline has been relentlessly pounded by rains, winds, and giant surf carving away at the shoreline cliffs that now drop nearly straight down for thousands of feet directly to the ocean. Year upon year the wind-driven waves explode against the rocky headlands, making the cliffs ever steeper and causing huge chunks of land to collapse into the sea. 
 Offshore the coral reefs fringing the island and are part of the whales’ habitat. This tropical environment is very different from the humpbacks’ summer waters far to the north. 
 Tlingit and Koholā swim along the coast about one mile offshore from the northeast tip of the island. They pass several small baysKē‘ē, Wainiha, and Lumaha‘i—and then come to the great sandy crescent of Hanalei Bay.
 A sizable swell is now arriving, and the waves are still growing in size. There are no boats in Hanalei Bay this time of year because its northern exposure provides no protection from the large winter waves. 
 Waves are breaking along the whole length of the Hanalei Bay shoreline. These waves form perfectly at the points on each side of the bay and at various spots along the great, curving shoreline. Surfers paddle their surfboards to catch the waves, and ride down the huge, curling wave faces.
 Perhaps unaware or at least unconcerned about all this surfing activity, the two whales swim onward, eventually reaching a rocky outcropping of land known as Kīlauea Point where an old lighthouse is perched atop the peninsula bluff. The opposite cliff is dotted with thousands of nesting red-footed boobies. Many birds circle above while others arrive and leave in a continual procession from their cliffside homes.
 Offshore of Kīlauea Point is a rocky islet is known as Moku‘ae‘ae, which means “Fragment frothing in the rising tide,” referring to the tumultuous whitewater created when the big waves hit the point’s craggy rocks.
Moku‘ae‘ae is the northernmost point of the main Hawaiian Islands, and the islet is the habitat of a multitude of other seabirds including petrels, terns, noddies, albatross, and shearwaters. Gliding high overhead are great frigatebirds as well as red-tailed and white-tailed tropicbirds.
 Some of these seabirds nest on the rocky cliffs or in burrows on the shoreline bluffs. Some of the birds are just passing by the Hawaiian Islands on their migratory pathsfrom every direction they come and go on their annual migrations that connect all of the Earth’s land and sea.
Pacific Golden Plovers
Pacific golden plovers, known to Hawaiians as kōlea, migrate to Hawai‘i each winter, just like the humpback whales. While the plovers fly the distance in just two or three days, however, the humpbacks take a few weeks to swim the distance. 
Plovers come to Hawai‘i to feed, and then fly north to polar regions to lay their eggs. This is just the opposite of the humpback whales, which feed in the north and come to Hawai‘i to give birth.


Chapter 6
Songs of the Humpback Whale
Koholā stays relatively close to her mother. Day by day Koholā learns about the various life forms in Hawaiian waters, and is often puzzled by the strange creatures she encounters. 
Koholā surfaces and sees a noddy bird plunge into the sea and emerge with a fish in its mouth. Beneath the water, she sees another diving bird penetrate the surface and scatter a school of fish in all directions. 
Koholā will become even more familiar with seabirds when she learns to feed in northern waters. There she will plow up through the swarms of krill and herring, and occasionally will scoop unsuspecting birds into her mouth as the birds dive down to catch the leaping fish.
As she swims along in the relatively shallow nearshore waters, Koholā suddenly notices a creature foraging along the bottom of the sea. It is a Hawaiian monk seal (Monachus schauinslandi), known to the Hawaiians as ‘ilio-holo-i-ka-uaua. The monk seal is about the same size as a dolphin but rounder and fatter, and uses its whole body to undulate through the water.
Koholā swims closer but this startles the monk seal, who swims away quickly and resumes the search for foodoctopi, lobsters, eels, and reef fish. Soon the curious seal returns to investigate the whales, circling around at a distance, but eventually both species 
Days roll by one into the next as Koholā learns from each new experience in tropical seas. Tradewinds blow strong off the sea and rise up the hillsides where the moist air condenses into billowing clouds creating small passing rainstorms over the hills and nearshore waters.
The rains give Koholā an exhilarating feeling as moisture falls through the bright sunlight forming a giant rainbow over the water. As evening arrives the sunset sky dazzles Koholā’s eyes with even more curious colors.
This same weather pattern continues for several weeks as Koholā increases in size and develops her skills. The bay waters are cradled by great stone cliffs and soft breezes play along the sandy shoreline.
The winds of these islands are rich with the scents of ferns and flowers, from the wild jasmine and ginger of the lowlands to the wind-twisted forests of ‘ohi‘a lehua and koa in the uplands. As Koholā swims near the shore, she senses the subtle differences in the ocean water, especially near the larger rivermouths. 
Native Birds of the Hawaiian Islands
Kaua‘i’s mountainous regions provide habitat for Hawai‘i’s many native bird species. In the forested uplands and mountains are such native avifauna (bird life) as the pueo (Hawaiian owl) and a variety of colorful honeycreeper birds, each with a specialized beak adapted to a specific food source. 
One of these honeycreepers is the ‘i‘iwi with its long down-curving bill, ideally shaped to feed from the long, cup-shaped flower of the native lobelia flower. The ‘i‘iwi beak and native lobelia flower fit each other perfectly.
On the slopes of the volcanoes live the nēnē, descendents of Canadian geese. Nēnē have adapted to walking on high, dry lava flows on Hawai‘i Island. Nēnē also take to the air and are seen gliding in formation over the lowlands and along the coast.
There is a history to these islands that Koholā perhaps also senses, a feeling of connection rooted in her evolutionary history. Deep in her genetic memory there may still be a link to those ancient days when whale ancestors walked on land, just as all life forms on land may retain some sense of their own ancient origins in the vast and mysterious sea. 
Tlingit was born in Hawai‘i’s tropical waters, and each year of her life the booming sounds of her breaches have echoed off these same seacliffs that rise above her now. For the last two thousand years the island’s tropical breezes have also carried the sounds of the native people, the Hawaiians. Their ancient chants accompanied the graceful and rhythmic movements of hula, the enduring passion of a people and culture interwoven with the land and sea.
For Tlingit and Koholā these tropical seas are home, yet only for a part of each year. The humpbacks’ life involves a migration between two worlds, Hawaiian and Alaskan waters, and each of these native places has its own separate purpose for the whales. Island waters provide shelter for mating and birthing while northern waters provide bountiful summer feasts.
Tlingit is quite exhausted from her recent activities, and her movements are now gentle and relaxed. She has completed her long journey from polar to tropical seas and has given birth to a healthy calf who now swims around exploring her new world.
Winter has ended and Tlingit feels the desire to begin feeding again. She would eat now if food was available, but the small fare she feeds upon is nowhere to be found in these tropical seas. Soon Tlingit will make the journey north and swim through great clouds of tiny ocean creatures that will once again nourish her massive body. 
Now nursing her young one in Hawaiian seas, Tlingit is beginning to feel the hunger for food. Yet the allure of these warm equatorial seas still remains. Hawai‘i’s tropical waters provide Tlingit with suitable conditions for the propagation of her species, and mating is once again a possibility.
When Tlingit left Alaskan waters in the fall, she weighed about 45 tons. Her weight is now down to just 37 tons, and won’t begin to increase until she returns north. Meanwhile Tlingit has little time to rest because her calf needs continual guidance and plenteous milk.
Both mother and daughter must gather their energies for the coming migration north. Koholā swims near Tlingit again to nurse upon her swollen mammary glands, and with an insatiable thirst the infant drinks gallon after gallon of the rich, nourishing liquid.
When she is not nursing Koholā, Tlingit meanders through the water, mostly milling near the surface or submerging only several feet before barely swishing her tail fluke to lazily move forward. Today Tlingit is in that half-awakened state, her body tired from the demands of migration and motherhood as she lounges in the land of leviathan dreams.
Unihemispherical Sleeping

Humpback whales must be at least partially conscious to breathe, and so they let just half of their brain sleep at a time. This is known as unihemispherical sleeping.

In the productive northern ocean Tlingit will feed upon great blooms of krill, copepods, and small fish such as herring, capelin, smelt, and sand lance. Using the long baleen strips that hang from her upper jaw, she will seine the tiny quarry from the sea. Tlingit’s frayed strands of baleen are woven together into a mesh that filters the minuscule prey from the ocean water.
 Tlingit suddenly becomes aware of a long, plaintive noise suffusing the water all around her. The song begins with a series of deep, rumbling low notes followed by long, wailing high notes as the pitch rises and then lowers again into deep bass tones. This is the mating song sung by the humpback male, and the sounds beckon the females of the species.
 The whale sounds emanate from about 400 yards away where a humpback is singing just beneath the surface. The ocean is alive with the sounds of the singer, and Tlingit can feel the song as much as hear it, absorbing it through her skin and sensing it with her many vibrissae, the long coarse hairs that emerge from knobby protuberances on her upper and lower jaws.
 The songs of the humpback whale have resounded through the ocean for many millions of years. To Tlingit, the songs are full of soothing and welcoming noises that stir inside her the urge to mate again. Perhaps the songs awaken memories of past winters in these tropical seas—being courted by males, mating, and becoming pregnant. 
 The male humpback’s symphony of sounds, from the deep booming bass notes to the tremulous high tones, attracts Tlingit and awakens certain instinctual feelings—for this is the species’ signature song.
 Listening to the song of the male humpback is calming to Tlingit even as it triggers a certain wariness due to all the work involved in raising a calf. Tlingit has given birth to four calves in the past seven years, including the recent birth of Koholā. 
The songs that now fill the water have started the rituals of reproduction once again, and Tlingit swims nearer to the sounds as she feels the vibrations pulsing through the water. 
Suddenly Tlingit breaches and then swims deep below. Her daughter follows and is excited by the strange and enticing noises she hears. As the two whales move nearer to the sounds they can hear the singing male humpback in his full glory.
Koholā feels the rumbling throughout her whole body as high and low tones vibrate through the water in long crescendos of repeating musical phrases that fill the sea with music. 
The singing whale is positioned just beneath the surface with his head down, as if suspended from above by his tail—this is a common singing posture. The sounds are new to Koholā, yet familiar, for this is indeed the language of her species.
Tlingit is impressed by the quality of this particular whale’s song. The series of tones is consistent and smooth, and the song continues for a long time between breaths.
Over and over the whale repeats the song, as if calling out to a potential mate and unwilling to stop singing until the mate is finally wooed. Hour after hour the singer perfectly reproduces the complete pattern, carefully regulating the song’s tone and volume.
Humpback Songs
Humpback songs consist of phrases lasting a few minutes each. Phrases are combined to form themes, and two to nine themes constitute a song. The song is a continuous vocal display that lasts anywhere from about six minutes as long as 30 minutes before it is repeated, often for many hours at a time. 
Humpback whales are able to emit a broad range of vocalizations despite the fact that they have no functional vocal cords. The whale produces these sounds by controlling implosive movements of air between a series of muscles, valves, and blind sacs that branch off the respiratory tract.
Humpback whales are prodigious singers, yet they don’t release air while singing. Instead the sound is created by forcing air into dead-end branches off the larynx or directed over a throat constriction. This is similar to how sound is produced by pinching a balloon near where the air is escaping. 
The acoustic range of humpback whales, from their lowest to their highest notes, exceeds all other animals, land or sea. Humpbacks use the whole span of this vocal range, and may produce two completely different sounds simultaneously.
Humpbacks may adopt a head-down position in the water while singing so more blood perfuses their brain, which is understandable considering the complexity and precision of the singing and the incredible memory required to repeat the lengthy songs. 
All of the humpbacks in an area sing the same general song, perhaps imitating the most successful singer in the hopes that it will bring them a mate. 
Each week the song being sung by a population of humpback whales changes by a small degree, and all the singers make this same change. Week after week, humpback whales alter their song just slightly, and so by the end of the mating season the song may be very different than it was at the beginning of the season. 
Humpbacks generally stop singing when they leave their mating and birthing waters. When the whales return the next year, all of the singers again begin singing the same song, taking up where they left off the year before. 
The humpbacks’ song-sharing behavior plays a key role in the species’ social dynamics as the song evolves simultaneously throughout the humpback population.
 Tlingit is attracted by the sounds of the singing whale, and now swims closer to the alluring rhythms. Little Koholā is a bit confused by these deep melodious tones pouring through the sea. She can tell that the noises do not frighten her mother, yet Koholā is still a bit wary as she swims toward the origin of the sounds.
Koholā swims ahead but then swims back around toward her mother for assurance, circling around Tlingit and staying relatively close. For Tlingit, the sounds reverberating through the water are a reminder that she is not yet finished with certain important activities that will occur here in Hawaiian waters, and Tlingit possesses other urges besides feeding. 
Several males in the area would like to mate with Tlingit. She is receptive, and will choose one of the whales, but this will almost certainly be Tlingit’s last year of mating, becoming pregnant, and giving birth—then the reproductive phase of her life will be over. 
Several males draw near, and then Tlingit gives Koholā a nuzzle as if to signal that she is leaving but will soon return. Then Tlingit slaps her broad tail onto the water, rolls onto her side, and submerges. 
Moments later Tlingit erupts from the water amidst a rainbow of spray and foam. Rising up to the peak of her breach, Tlingit lets out an explosive exhalation as she spirals upward and spins around 180 degrees. 
Again Tlingit launches skyward, her 15-foot pectoral fins extended out to her sides as she whirls around and gains a brief view of the whole panorama of the island/ocean scene. Just as quickly she comes down onto the surface with a booming splash.
Onshore the steep seacliffs rise precipitously from the breakers. Garlands of mist encircle the upper peaks and hide the origins of waterfalls that seem to fall from the sky. Tlingit swims back down into the ocean, her elongated fins extended like the wings of a giant bird soaring through the depths. 
Long-jointed bones run the length of Tlingit’s pectoral fins, making them nimble and flexible. She bends the fins gracefully as she glides through the ocean water. 
Tlingit breaches again and lands with a huge splash. Where her giant body enters the sea the great volume of displaced water creates a vacuum of air. Then the water rushes in again from all sides, sending up a secondary splash as Tlingit’s massive form disappears beneath the surface. She breaches not only to view her surroundings, but also to make sounds on the surface that other whales will hear. 
Tlingit finally ceases her aerial displays and lingers for a few minutes near the surface. Then she begins to swim rapidly, and suddenly turns and dives straight down. Minutes later Tlingit again flies up from the water in a full breach, and now her behavior distinctly changes. She moves along the surface purposefully, swimming rapidly, and with three other humpback whales now swimming in formation behind her. Such a grouping of males in close formation behind a receptive female is known as a competition pod.
The whales are courting Tlingit’s favor as each whale tries to displace the others from the front position nearest Tlingit. This closest male behind Tlingit is known as the primary escort, and is in the ideal position for winning the favor of Tlingit and being given an opportunity to mate with her. 
Tlingit tests her suitors, taking them through a series of turns and maneuvers—up and down and left and right—all this to challenge the strength and coordination of the whales competing for the position of the primary escort. 
Over a period of several hours, the competition pod is put to the test by Tlingit. They bump and jostle each other, occasionally breaching and then coming down from above to inflict punishment on the whale below by hitting the whale with their hard jaw plate. Finally one of the whales distinguishes himself without a doubt, and it is this male that has proven himself the most worthy of mating with Tlingit.
Tlingit and the primary escort now begin a series of close interactions, including the touching of pectoral fins and bellies, and much diving around and over and under one another. The other escort whales linger nearby, aware that their attempts at courtship were unsuccessful. 
Tlingit and her mate continue their interactions, including slapping their pectoral fins on the water’s surface. The male turns on his back with his belly above the water and repeatedly hits both fins down onto the water, each time bringing his fins up and crossing them over his stomach before slapping them back down onto the water on either side of his body. 
Soon the two whales swim underwater together away from the others. There in crystal blue Hawaiian seas a humpback whale is conceived.


Chapter 7
More Dolphin Encounters
 In about one month Tlingit will be back in Alaskan waters feeding on the bounty of sea life. Herring, krill, and copepods will fill the northern waters so thickly that she’ll need to expend very little energy to acquire food. She’ll take in great mouthfuls of the fish-filled water and strain the catch through her fringed baleen plates. Eventually Tlingit will regain the weight she lost during the winter months, and the food she eats will nourish yet another infant humpback whale.
For hours upon hours Tlingit will swim through dense swarms of krill, her gaping mouth surging through the enormous clouds of underwater life like a giant mower plowing a path through the sea. 
Tlingit may eat two, three, even four tons of food per day, rejuvenating her energy and providing her with the strength she will need for the next migration south. Here in Hawaiian waters, however, there is little for Tlingit to eat, yet Hawai‘i’s tropical seas are a perfect environment for other important activities, such as mating and giving birth. 
Just days after her encounter with the male humpback, Tlingit feels a subtle sensation that indeed a seed has been planted within her. Yet the tiny whale now inside Tlingit’s belly will not begin to grow until she reaches the northern feeding waters. Then the fetal cells will begin to divide and multiply at a rapid pace as the mother feeds and also returns her own body to full size in the northern seas. 
By the end of summer the whale inside Tlingit will have grown to weigh over one ton. Then, as the water grows colder again, Tlingit will repeat her annual southern migration to Hawai‘i where she will give birth.
Now rounding the point and gliding into Hanalei Bay, Tlingit and Koholā come upon some dolphins that are different than the spinner dolphins they encountered earlier. These are bottlenose dolphins (Tursiops truncatus), which look somewhat similar to spinner dolphins, but are larger and have a distinct, robust snout.
Tlingit has encountered bottlenose dolphins many times before, and she swims on unconcerned. Koholā is curious and swims near the new visitors, noticing right away that the dolphins are a bit different than others she has met.

Bottlenose Dolphins

The Hawaiian name for dolphins is nai‘a. Bottlenose dolphins are found in virtually all oceans except at higher latitudes. Sleek, streamlined creatures that dive over 150 feet for food, they often stay underwater more than ten minutes. A bottlenose dolphin trained by humans once dove 1,795 feet, though dolphins don’t often dive so deep on their own.

The dorsal fin of the bottlenose dolphin is taller than the spinner dolphin’s dorsal fin, and also more curved back, or falcate.

One of the bottlenose dolphins swims below and playfully exhales air that floats upward and dissipates as it hits Koholā, who is exhilarated by the feeling of the air bubbles on her skin. 
Tlingit breaches and then swims deep below as Koholā continues to watch the dolphins, circling around curiously but then swimming deep underwater after her mother. When the two whales come to the surface again, the dolphins are particularly curious about Koholā, and then swim nearer to investigate her. 
Koholā is excited at the nearness of the dolphins, and is also interested in their strange activities. Koholā sees that they aren’t much bigger than her, but so very different. Using echolocation, the dolphins are able to sense how excited and curious Koholā is about them also.
The dolphins repeatedly swim around the two whales and send out echolocation pulses. These particular bottlenose dolphins are resident to this coastal area and only venture into deeper waters to feed. This is different than some other groups of bottlenose dolphins that swim the distance between the islands. 
For a short time the dolphins continue to encircle the two humpback whales as they all swim near the mouth of Hanalei Bay. Tlingit is unfazed by the encounter, surfacing to breathe and continuing on in her own relaxed rhythm of aquatic movement. Koholā leaps above the water in a full breach as she follows after her mother.
Tlingit’s graceful movements in this watery world hide the fact that her ancestors walked on land. Tlingit is not conscious of her species’ terrestrial past, nor is she concerned with the principles of evolution by which populations of species change over time—perhaps only humans ponder such things.
Tlingit herself will not evolve, though her species as a whole will evolve over many generations. The evolution of a species occurs not in one or two lifetimes, but over thousands and millions of years.
Evolution occurs solely on the basis of some individuals of a population of a species, such as humpback whales, giving birth more than other individuals of the population. These particular members of the population that are more successful at reproducing pass on their particular traits to the next generation, and so that trait becomes more common in the population.
Mesonychids—The Ancestors of Whales
More than 50 million years ago some land mammals that were slightly bigger than dogs but smaller than bears began to venture into the shallow coastal waters searching for food. These were the mesonychids, the terrestrial ancestors of whales, and they looked somewhat like the hyenas of today. 
The mesonychids’ forays into the aquatic realm were driven solely by the species’ need to survive. The terrestrial habitat of the mesonychid did not provide sufficient food, and so the mesonychids increasingly ventured into the sea in search of feeding opportunities. 
Over many generations the mesonychids evolved small variations in their physical traits, including wider tails that allowed them to stay underwater longer and get more food. Individuals with beneficial traits were generally stronger and healthier, and consequently had more offspring, thus passing on their favorable traits.
The sea provided food, and so traits that were beneficial in the aquatic realm were favored by the evolutionary process of natural selection. Generation by generation, the overall mesonychid population changed, with each generation becoming slightly better adapted to venturing into the water for food. In this way the species as a whole became more efficient when pursuing prey in the ocean. 
Over many thousands of years, the body of this ancestral whale became more elongated and streamlined as it adapted to the ocean environment. The hind limbs became smaller and eventually disappeared altogether as the forelimbs lengthened and flattened, becoming pectoral fins. 
The nasal passages migrated to the top of the head to become the blowholes, allowing for more efficient breathing at the surface. The teeth of the evolving species disappeared as baleen evolved to strain small prey from the sea. 
Perhaps the most critical trait that evolved in the ancestral whale species was the flattening of the tail into a broad, horizontal fluke that increased propulsive power and helped the whale capture prey. 
The evolving fluke, powered by the undulations of the entire back half of the creature’s body, also provided the power for a significant breaching ability that in turn allowed for more effective vision and communication. The powerful tail region also helped the whale defend itself in the unpredictable, undersea world.
All of the attributes that humpbacks possess today developed over time through the process of natural selection. These traits, by definition traits that increased the species’ chances of survival in their ancient ocean habitats.

Humpback Evolution

Humpback whales are the products of the entirety of all of their ancestors’ past habitats. It was the buoyant medium of water that allowed the baleen whale to attain its huge stature. A similar sized creature on land would need much more energy to maneuver and would need a much more massive skeletal structure to support its weight.

Environment dictates form and function, and because environmental conditions change over time, so do species — this is according to the theory of evolution and the principles of natural selection.

This is also why, in modern whales, we still see reflections of their ancient past, as natural selection is the driving force of the species’ physical changes.

The form of the humpback whale today is a reflection of all of the specific habitats where it struggled to find food and survive. Some adaptations, or traits, that have persisted in the anatomy of humpback whales are traits that were beneficial to their survival and reproduction in ancient oceans.

In the teeth that recede into the fetal whale’s gums before birth, we see a remnant of the humpbacks’ toothed ancestors that survived in ancient oceans before humpbacks evolved baleen that helped them feed on large quantities of small prey. The humpbacks’ vestigial bones are remnants of their now-disappeared hind limbs.

Traits that are still present in today’s humpback whales reveal the species’ storied past. Looking at a modern humpback whale, we may discern its behaviors by the shape and structure of its intestines, which reveal its current diet. The humpback’s dual-lensed eyes reveal the duality of the whale’s habitat above and below the surface.

The humpback’s enhanced abilities to transmit sound reveal the evolution of its communication abilities specifically adapted to the properties of acoustic transmission in water.
 Just as the baleen whales’ long pectoral fins and wide, powerful tail fluke evolved for propulsion, feeding, and defense, they also evolved a super-sized mouth for efficient feeding. 
These evolutionary processes occurred over millions of years as the emerging cetacean species of humpback whales evolved from the mesonychid, a hoofed, shore-dwelling mammal that walked on land some 65 million years ago before venturing back into the sea to become a fully aquatic mammal.
Tlingit’s distant ancestors were terrestrial creatures, yet to her the land is a foreign place that is not her domain. In the past she has heard the distressed cries of stranded and beached whales, and she also knows the perils of strange northern waterways where whales are sometimes trapped by quickly changing tides. 
Many years earlier, during the peak years of commercial whaling, the water around Tlingit was filled with the blood of dying whales. Tlingit was very young when the killing stoppedthe memories linger now only in the back reaches of her mind, barely there. Perhaps even deeper in Tlingit’s memory, passed down through her direct ancestors, there is some distant recollection of those experiences that threatened the very survival of humpbacks they were hunted mercilessly throughout the world’s oceans. 
Tlingit and Koholā now swim through Island waters that appear unthreatening to the whales. They sometimes come across sharks or other marine life, but for the most part the whales’ days are uninterrupted by any need for defensive behaviors. Occasionally a boat will cut off their path or approach too rapidly, and when this happens Tlingit submerges and swims away with Koholā following. The whales sometimes swims closer to the boats for a curious look, and this usually causes boat captains to shut off their engines in order to quietly observe the beautiful marine mammals. 
 The coves and bays of the Hawaiian Islands are mostly welcoming and free of predators, but when Tlingit and Koholā begin their journey north they will leave behind the relative safety of tropical seas. 
In the open ocean and far northern waters of the Pacific, pirate whalers continue to prey on the humpback species. Also found predominantly in northern waters is Ornicus orca, the killer whale, the most voracious natural predator of the humpback whale. Young humpbacks are particularly vulnerable to orcas.
Chapter 8
Leaving Hawaiian Waters
It is early May now and most of the humpbacks have headed north. Spring is in full swing, and all along Kaua‘i’s northern shores the warm breezes are cradled by great stone cliffs. 
Tropical tradewinds rise up the mountain slopes where the air cools and condenses into billowing clouds that create small passing rainshowers. The uplifting winds release their quarry of moisture and spawn rainbows that tint the horizon with radiant tropical light. 
Huge ocean swells roll in from the open ocean and crash against the cliffs. Wave after wave pounds against the coastline rocks, slowly but relentlessly carving away at the towering ramparts that rise up steeply from the sea. Tlingit and Koholā will head north soon, and they will be among the last of the humpbacks to depart Hawaiian waters on their annual migration. 
The ocean temperature around the Hawaiian Islands has already risen almost two degrees from its winter low, gradually increasing as summer approaches. Onshore the emerald green mountains glow in the bright sun. Recent rains have energized the waterfalls that cascade off the sheer cliffs with a thunderous roar before gathering in the lower valleys and then empty into the sea.
A week of constant rain has muddied the nearshore waters and turned the river estuaries murky brown. With each downpour and powerful storm, the hills lose another layer of earth to the process of erosion. Year after year and layer by layer, the island returns to the sea.
The steady downpour of rain has ended now, and Tlingit and Koholā swim in a peaceful ocean. A single day of bright sun has dried the island’s white sand beaches. About a mile from where Tlingit and Koholā now swim, two other humpbacks breach from the water simultaneously. One of them is a calf, like Koholā, and she breaches twice more while her mother swims below. 
Koholā is aware of the nearby activity and cautiously swims toward the other whales before swimming back toward her mother. Again Koholā hears and also sees the other calf breach, and she responds by energetically circling around Tlingit and then diving down into the water with an increased level of energy.
One of the distant whales breaches again. These two newly arrived humpback whales spent the winter months in waters off Hawai‘i Island (the Big Island) after the young one was born, and now have now ventured to Kaua‘i at the north end of the Hawaiian Island chain. Like Koholā and Tlingit, these whales will also soon begin their migration north to Alaskan waters. 
This is the last night in Hawaiian seas for Tlingit and Koholā. Tlingit feels the natural urge toward migration, and she moves deliberately in the prevailing current. Koholā follows, already sensing that this is part of her destiny, though not fully aware that it will be just her first ocean crossing along a migratory path she will eventually follow during every year of her life.
Koholā has actually traveled the distance between Hawai‘i and Alaska twice before. The first time, going north, Koholā was barely a group of cells inside Tlingit. Koholā remained in this dormant embryo state until her mother reached the feeding waters and began to find nourishment, and the time for increase began. 
On Tlingit’s journey back south after summer was over, Koholā was still unborn, though growing rapidly in Tlingit’s womb. Now Koholā is her own free-swimming being, a humpback whale beginning her first migration across the vast sea to distant northern waters. 
Tlingit continues to swim north, not randomly now, but purposefully. Koholā senses this change in her mother’s behavior as well as the changes in her ocean environment. As the evening sky begins to darken, a different horizon greets Koholā’s eyes when she comes above the surface. She is still a bit confused by the bright celestial sphere above, the vast sky glittering with stars barely conceived by her infant cetacean eyes. 
On the night Koholā was born, she was greeted by the huge white orb of the moon, which then reappeared each night as it gradually diminished to nothing and then slowly grew full again. This slow cycle of the waxing and waning moon is now starting to become familiar to Koholā, just as she has already become familiar with the sun’s daily movement across the sky. 
Tonight the moon is once again full, a bright beacon shining over Tlingit as she nurses her calf near the sea’s surface. A gentle swell rocks the water as a fine moonlight glazes the silver-colored sea.
Tlingit and Koholā have now begun their journey north toward polar waters. There food will be plentiful and they will feed among all of the other North Pacific humpback whales. 
The journey across the open sea will be a familiar one to Tlingit, though still it will not be easy. For the young Koholā the journey will be especially difficult, but also constantly exciting and full of new discoveries. Koholā will encounter many species not seen in tropical waters, which are so far the only waters she has known.
When Koholā arrives in northern waters, there will be strange landforms rising up from the shores. She will see glaciers calve and eagles soar overhead, and she will swim near bears at the river mouths clawing salmon from the water. 
Koholā will also encounter other whales that are very different from herself, such as the narwhal with its unicorn-like tusk, and the beluga with its canary-like whistles. A very different world lies ahead for Koholā.
As she swims north, Koholā notices the ocean temperature slowly decreasing and the water currents changing. Subtle variations in color and water composition occur with each degree of higher latitude, and Koholā is a bit confused about the different character of the sea around her. Even the sky looks different. 
The ocean where Koholā now swims is so deep she cannot see the bottom, even when she swims hundreds of feet below the surface. Above the water there is no land in sight, and Koholā struggles to keep up with her mother. For the first time the youngster cannot rest when she is tired and must follow her mother across an ocean that now seems infinitely deep. With her young one in tow Tlingit pushes on, vigilant to the mission of migration. 
Koholā’s primary fear in this new and foreign world is separation from her mother, her sole source of food (mother’s milk), and her only link to the knowledge she will need to survive. Koholā catches up to Tlingit and nuzzles against her, signaling a desire to feed. Not so easily persuaded, Tlingit continues on a steady pace toward northern waters. The young one’s persistence finally wins out, however, and Tlingit pauses as rich milk flows into Koholā’s mouth. The two whales are now about 50 miles north of the Hawaiian Islands.
Suddenly Tlingit is alerted by a dark form rising from below, but quickly recognizes the creature as non-threatening. It is a dense-beaked whale (Mesoplodon densirostris), brownish-silver in color on top and white underneath. The whale weighs about two tons and measures just over 14 feet long, which is about average for mature members of this species. 
Koholā is close by practicing her breaching, and the splashes of her pectoral fins and tail fluke cause Tlingit to circle around and dive below before gliding upward toward her calf. Koholā sees the dense-beaked whale and is aware that this creature is somewhat alike but also very different than herself. Two oversized teeth protrude upward from the mouth of the dense-beaked whale. 
Koholā begins to swim away before looking back curiously and noticing the many marks all over the whale’s body. The marks were caused mostly by altercations with other dense-beaked whales, and this particular whale that Koholā encounters is quite old and bears many scars.
As the dense-beaked whale nears the surface, its teeth poke up out of the water. The whale thrusts its chin and rostrum above the surface and then submerges its front as its dorsal fin appears.
Dense-Beaked Whales 

Dense-beaked whales are also known as Blainville’s beaked whales. Until 1922, no dense-beaked whale had been found alive, and 26 species were found in museums. There have been encounters since then, but sightings remain rare, including strandings on Hawai‘i’s Leeward Islands.

The two very different whales look at each other quite closely, and rather than scaring Koholā, the eye contact somehow calms her. Perhaps Koholā senses that this other creature is similar to her, or at least less different than other creatures she encounters in the ocean.
The Dense-Beaked Whale
The dense-beaked whale is a deep-diving, toothed cetacean that feeds on squid and fish. The male of this species has two large barnacle-encrusted teeth, each about eight inches long. These prominent teeth stick straight up from the sides of the whale’s lower jaw. 
 Dense-beaked whales are rarely seen by humans, and prefer very cold water. The species is more common in Hawaiian waters than anywhere else because Hawai‘i’s offshore waters get deep very quickly compared to continental waters. This rapid drop-off in depth makes the cold, deep water readily accessible to the dense-beaked whale.
The temperature of the ocean beneath about 3,000 feet deep is just above freezing. This is true in all the oceans at all latitudes, from the equator to the poles.


Chapter 9
Back in Northern Waters
About three weeks after leaving Hawaiian waters, Tlingit and Koholā finally reach their destination, the food-rich northern seas where Tlingit begins to partake in a summer feast and regain the weight she lost over the long winter without food. 
Koholā is still nourished each day by her mother’s milk, and continues to grow rapidly, about one foot per month. The young whale will double in size during her first year of life.
 Above the rolling swells of water, Tlingit sees Alaska’s Kodiak Island where huge brown bears onshore lumber alongside a river. These are grizzly bears, Ursos arctos horribilis, the largest bears on Earth. These particular grizzlies are also known as Kodiak bears. 
 One of the large Kodiak bears walks into the river’s current and then swoops its massive paw down to claw a salmon from the rushing water. The salmon are born high in the mountain lakes and streams and then swim downriver to the ocean. Years later the salmon return upriver to their home waters to spawn the next generation. 

To Tlingit, the movements of these strange creatures she may see on the shoreline are only a mild curiosity. Tlingit swims along at a moderate pace, about five miles per hour, surfacing every few hundred feet for another breath of air while occasionally diving beneath the sea in search of food.

Occasionally Tlingit ventures into coves and bays to explore some feeding opportunities. In one of these bays she comes upon a northern sea lion, a large marine mammal quite common in these waters. Tlingit veers to the right, inspecting the sea lion closely with her left eye.

The young male sea lion is about seven feet long and 700 pounds, and swims around Tlingit in a smooth circle. The seal then surfaces as Tlingit surfaces, and together the two different species take a breath and re-submerge, casually inspecting each other before going their separate ways. Within two years this young sea lion will weigh more than one ton and measure more than twelve feet long.


Chapter 10
One Year Later Continuing On
In southeast Alaska, off the northern shore of Mitkof Island where the Fredrick Sound meets the fast-flowing Wrangell Narrows, tall masts of boats sway gently in the Petersburg harbor. North of the tiny, seaside town a half-dozen bald eagles look over the inlet waters. These white-crowned birds benefit from plenteous salmon they pluck from the water with their razor-sharp talons.
After an unsuccessful feeding attempt, a young eagle alights on a branch. The eagle’s feathers are still a mottled colorshe won’t gain her adult plumage until about five years of age. The eagle’s body, like Koholā’s, is still changing even as the bird develops better hunting skills.
Koholā has now completed her second journey north from tropical waters, and has chosen this location as her primary feeding area during the first year apart from Tlingit. Koholā was born in Hawaiian waters, traveled with her mother to Alaskan waters, and then swam back again to Hawai‘i’s tropical seas. On her second journey north, Koholā left the tropics before Tlingit. Koholā is now on her own off the southeast Alaskan coast.
Hungry from her long journey, Koholā feeds on huge schools of fish and continues to grow in size and strength. She is well on her way to reproductive maturity, which will occur around 4½ years of age, though full physical maturity won’t come until about eleven years of age.
Koholā has now begun to understand the seasons of her life as a humpback whale migrating between the two worlds of the tropical and polar waters. The brief northern summer is marked by a frenzy of procreation among life’s smallest creatures, and is the time to eat large quantities of food. Winter in Hawaiian waters is the time when calves are born and whale songs fill the sea, signaling the rituals of mating and birthing. 
When Koholā was just a few months old and arrived in northern waters after her migration from the tropics, she quickly discovered an ocean full of life. Koholā fed on Tlingit’s rich milk while she learned about her new environment in northern waters, the other half of her native habitat.
During summer months in Alaskan waters the vast soup of the sea transmutes life into more life. Large creatures feed on the small, and the smallest feed on the thick broth of microscopic plankton at the base of the food chain. A combination of sunlight, minerals and nutrients create a rich diversity of life that blossoms before Koholā’s eyes.
Koholā’s first winter in Alaskan waters was full of new experiences and she encountered many other humpback whales as well as a great variety of other marine life. As winter approached she headed south with Tlingit, and the northern sea became dormant and seemingly lifeless. 
Now millions upon millions of tiny creatures once again fill the northern sea, a teeming bounty unmatched in any ocean. The flourishing marine organisms are a testament to the abundance and diversity of lifeits profound interconnectedness, complexity, and beauty. 
Protists, fungi, lichens, vascular plants, krill upon krill, and an endless array of marine life forms fill the water. Between the tiny krill are even tinier creatures called diatoms, which are one-celled, glass-armed algae. This microscopic ocean life at the bottom of the food chain supports the most massive mammalian creatures of the ocean, including Tlingit and Koholā.
The sun is the primary energy source of virtually all ocean life including plankton, the mediators of Earth’s solar energy. The term plankton refers to aquatic species at the mercy of the ocean’s currents. Many types of plankton are able to achieve some small-scale movements on their own, though it is primarily the water currents that provide transport. Plankton harvest the energy of the sun and pass it on through the food chain to more complex life forms.
Many varieties of phytoplankton, the ocean’s primary producers, gather the energy of the sunlight and convert it to energy in a process called photosynthesis. 
A magnesium-based molecule called chlorophyll is used by the phytoplankton to complete this conversion of sunlight to energy, and the long days of the Alaskan summer provide ample hours of sunlight for photosynthesis to occur.
Virtually all ocean life depends either directly or indirectly on phytoplankton. As the solar collectors of the sea, phytoplankton thrive near the ocean’s surface where they absorb sunlight and synthesize it into energy. 
Phytoplankton are eaten by zooplankton, and both are eaten by fish—all three are eaten by whales. Inevitably, all life in the sea is either eaten or decomposes on the seafloor where bacteria transforms it once again into the food chain’s basic nutrients, including phosphates and nitrates that support photosynthetic organisms. 
Winds move the sea’s surface waters, which are in turn replaced by water rising up from below. This upwelling carries the nutrient-rich waters from the ocean deeps up toward the surface, and drives the marine food chain processes. 
Suddenly great clouds of rising bubbles shatter the tranquility of the ocean’s mirrored surface. The large circle of bubbles is coming from several whales working together to corral nearly one million herring into a confined area so they may be eaten.
In close formation the whales, including Koholā, swim below the trapped fish. The whales, in close formation and with their cavernous mouths fully open, rise up through the trapped prey. The herring are enveloped in the frothy prison of air and are confused and helpless as they bump into one another and leap above the surface. Swirling in a mass frenzy, the herring are unable to sense the titanic forms coming up from below. 
Koholā opens her massive mouth and surges up through the trapped school, taking in thousands of gallons of fish-filled water. The whole front half of Koholā’s body expands like a giant balloon, revealing the folded skin of her ventral pleats, or throat grooves.
Spilling out the sides of Koholā’s voluminous mouth are the herring lucky enough to escape. The remainder of the fish see only darkness as Koholā uses her baleen to strain them from the water, and then uses her huge tongue to push the fish back toward her throat and swallow them in large gulps.
Koholā participates in this feeding as part of a cooperating group of humpback whales, and the coordinated efforts benefit them with abundant food.
Days later, Koholā swims alone as she comes upon a great cloud in the water. It is a mating swarm of krill concentrated in one area, and thus particularly vulnerable to the feeding techniques of the humpback whale. Koholā swoops below the krill and rises with her mouth fully agape. 
Again the shape of Koholā’s body is transformed as she takes in thousands upon thousands of the tiny prey. The front half of Koholā’s body expands and the ventral pleats widen with the inward flood of water. 
Koholā strains the huge quantity of food through her baleen and begins releasing the water as she swallows the krill. The water streams out of Koholā’s mouth as the baleen traps the tiny organisms like a giant sieve. Koholā’s tongue shovels the food into her throat, which then contracts and swallows in great gulps as the krill begin a journey through Koholā’s several stomachs.
And so we will leave the whales where we joined them, in Alaskan waters thick with herring and blooming with krill, waters surrounded by snow-capped peaks where eagles fly and bears prowl the rivers for salmon. Koholā is growing and thriving in these northern waters, and soon she will return to the tropics to fulfill her role in the perpetuation of her species. 
Tlingit and Koholā also enjoy the summer bounty of food as the two whales continue on through their annual cycle of seasons and migrations.
Gentle Giants
Humpback whales are among the largest and most graceful creatures inhabiting Earth’s seas. Their huge streamlined bodies glide through the ocean with ease, and two strokes of the powerful tail fluke propels the whale’s giant body up from the surface where it spins around in midair before landing with a thunderous splash. Yet humpback whales came very close to extinction due to commercial whaling.
Seeing humpback whales in their natural element is an awesome experience, and the fascination only grows as one learns more about these magnificent and highly-evolved marine mammals. Yet our understanding of humpback whales remains shallow, and we are often as perplexed as we are informed. With each new fossil or fact, each new study or reformulated conclusion, many new questions arise.
During nearly two centuries of intensive commercial whaling, humans learned a great deal about the humpback whales’ commercial value, how to hunt them profit from the sale of their flesh, yet little was discovered about the whales themselves—their migration, social structure, feeding, mating, and birthing. 
Modern science has only just begun to provide an understanding of the whales’ life processes and social relationships, and relatively little is known about their pronounced and subtle patterns of living. Many things remain a mystery, such as the complexities of cetacean communication methods, including the humpbacks’ structured and lengthy songs that resonate through the ocean deeps. Future studies will reveal more about the whales’ methods of sound propagation, including their amazing ability to use the broadest vocal range of any species of the land or sea. 
Recent fossil finds have shed new light on the evolutionary origins of whales. Fossils such as Ambulocetus inachus and other “missing link” fossils are now helping researchers understand how modern whales came to be, and scientists are utilizing new DNA analysis techniques to unravel the many phases in the evolutionary history of whales. 
The puzzle is far from solved, however, with much yet to be learned about the ancestors of whales and their slow change over time from an ancient land mammal species into the multitude of cetacean species that inhabit the oceans today.
Just decades ago, numerous whale species were on the brink of extinction due to commercial whaling. Some of these endangered cetacean populations, including the North Pacific population of humpback whales, have now significantly recovered, while others remain extremely endangered. 
Ocean pollution is a continuing threat to the largest of the whales. Many smaller whales and dolphins continue to die as the unwanted by-catch of commercial fisheries that seek tuna and other fish.
 Humpback whales are the gentle giants of the ocean, and they are the products of millions upon millions of years of evolution, yet they came very close to vanishing forever. The days of large scale commercial killing of humpback whales are over, and enough humpbacks somehow evaded the onslaught of whaling ships and harpoons to prevent the species from becoming extinct. 
 The humpback whales in the oceans today are the living links to the distant past, and their evolutionary history mirrors the processes of evolution of all aquatic and terrestrial life on Earth. 
While the modern history of the humpback whale is a stunning example of how profit is sometimes pursued at the expense of a species, the continuing story of humpbacks tells us that eventually human goodness may prevail as concerned individuals rally to save a unique and irreplaceable marine mammal. 
Humpback whales are as mysterious as they are fascinating, and learning about them is a step towards saving them and preserving the ocean environment where they live. 


Appendix 1:
The Evolution of Whales
and a
 Brief History of Life on Earth
15 billion years ago: The universe is born in an explosion called the Big Bang. Out of a chrysalis of gas and dust there coalesces a substance called matter, which eventually forms into stars, galaxies, planets, and a variety of other stellar objects. 
Over 100 billion galaxies form, including the Milky Way Galaxy, which contains about 200 billion stars. One of these stars is our sun.
4.5 billion years ago: Earth forms, 93 million miles from the sun. Earth is the third farthest planet from the sun, and one of nine planets revolving around the sun, which is the center of the solar system. Earth is the fifth largest planet, and has one moon, which orbits the planet every 29 days.
4 billion years ago: Life takes hold on Earth, most likely in Earth’s oceans.
570 million years ago: Sponges and other multicellular organisms evolve in Earth’s oceans, followed by increasingly complex multicellular life.
468 million years ago: Life takes hold on land in the form of simple plants. 
370 million years ago: Lobe-finned fish appear. They use their bony front limbs to climb onto land in search of food. 
Reptiles evolve from lobe-finned fish and eventually branch out into many land animals, including mammals, dinosaurs, turtles, and other groups. 
225 million years ago: Dinosaurs appear for the first time, along with the ancestors of modern mammals. Dinosaur species soon dominate the land.
213 million years ago: Thirty-five percent of all animal families become extinct, including all marine reptiles except ichthyosaurs. Dinosaurs expand into many terrestrial habitats. 
150 million years ago: Sea turtles inhabit Earth’s oceans.
65 million years ago: Another mass extinction occurs, most likely due to an asteroid impact that devastates dinosaur populations. 
Only very small mammal species exist on Earth at this time, and with the dinosaurs gone, many mammal species evolve into larger species, including the mesonychid, a hoofed shore-dwelling mammal that is the direct ancestor of whales. 
The mesonychid is about the size of a large dog or small bear, and roams the shores of a large body of water called the Tethys Sea.
60 million years ago: Mesonychids, the ancestors of whales, begin to venture back into the oceans to search for food. As each generation of the species spends more time in the water, evolution brings about gradual changes allowing the species to become better adapted to the aquatic environment. 
Over the following tens of millions of years, the hyena-like mesonychid species evolves new aquatic traits: the forelimbs lengthen into pectoral fins; the hind limbs gradually become smaller until they finally disappear; the body becomes more streamlined; the nasal passages migrate upward and back on the head to become the blowholes; and the head becomes broader as the body narrows toward the lengthening tail for more streamlined and efficient aquatic movement. 
The mesonychid’s tail becomes more flattened on the end, and this lateral flattening eventually leads to the horizontal tail fluke that propels the animal gracefully through the water.
53.5 million years ago: Appearance of Himalayaecetus subathuensis, considered the oldest whale.
50 million years ago: The primitive whale Pakicetus inachus appears.
49 million years ago: An archaeocete called Ambulocetus natans (“The walking whale that swam”) appears. This otter-like whale ancestor is about 10 feet long, 650 pounds, and has shark-like teeth, but does not yet have the horizontal tail fluke of modern whales.
46 million years ago: The whale ancestor Rhodocetus appears, and has the beginnings of a tail fluke.
40 million years ago: Basilosaurus isis appears. This whale ancestor has a body up to 65 feet long, and a well-developed tail. The evolving mesonychid has now made the transition from a land-dwelling mammal into a fully aquatic mammal.
30 million years ago: Two main evolutionary lines of cetaceans emerge—the baleen whales and the toothed whales. 
The baleen whales develop giant mouths with fringed plates of baleen that are used to sift tiny prey from the water. Toothed cetacean species hunt larger prey, and work together in cooperative hunting and feeding strategies.
10 million years ago: Humpback whales inhabit the world’s oceans.
5 million years ago: The island of Kaua‘i forms. It is the oldest and northernmost of the eight Hawaiian Islands.
4 million years ago: The first hominids (the ancestors of humans) appear. Called Australopithecus afarensis, they stand upright and walk on two feet.
100,000 years ago: Homo sapiens (modern humans) first appear.
c.1,700 years ago: Approximate time of first humans arriving in Hawaiian Islands. Estimates of the time of first human arrival range from A.D. 100 to A.D. 800.
Today: The scientific order Cetacea includes all whales, dolphins, and porpoises. Cetaceans are carnivorous, aquatic mammals found in all the world’s oceans. 
 There are two main evolutionary lines of cetaceans: baleen whales (mysticetes), and toothed whales (odontocetes). At least five species of baleen whales are native to Hawaiian waters, along with at least 19 toothed species.


Appendix 2
Guide to the Taxonomy 
Of the 
Humpback Whale
Kingdom: Animalia: 
All animals are part of the Kingdom Animalia.
Phylum: Chordata: 
All chordates possess a notochord, which is the precursor to the backbone. The notochord is basically an internal skeletal rod of either bone or cartilage.
Subphylum: Vertebrata: 
Vertebrates are the most advanced group of chordates, having a skeleton that supports appendages (fins, or arms and legs) and a cranium, which protects the brain. All animals with backbones are vertebrates. 
The most primitive vertebrates are fish, which give rise through evolution to amphibians (which have four limbs); and then reptiles (the first to colonize land); and eventually dinosaurs and birds. An offshoot group of reptiles eventually gives rise to a class called Mammalia, including humans.
Class: Mammalia: 
Mammals suckle their young and are characterized by hair and different-shaped teeth. Mammals are also warm-blooded, which means they can regulate their own body temperature.
Primitive mammals include monotremes (egg-laying mammals), and marsupials, which keep their young in a specialized pouch. Advanced mammals are called placentals, and this is the group that includes both the order Cetacea (whales, dolphins, and porpoises) and Homo sapiens (humans).
Order: Cetacea: 
Cetaceans include all whales, dolphins, and porpoises. The order Cetacea is divided into two suborders: Mysticeti (baleen whales) and Odontoceti (toothed whales).
Suborder: Mysticeti: 
Includes all the baleen whales. Mysticetes are characterized by two blowhole openings, a symmetrically shaped skull, vestigial leg bones, and the use of baleen for feeding. 
Note: The Suborder Odontoceti includes all cetaceans with teeth. Odontocetes are characterized by a single blowhole, an asymmetrically-shaped skull, no vestigial leg bones, and the fact that they have teeth, which are used for feeding. 
The Suborder Mysticeti includes three Families: 
Ø Humpback, fin, sei, Bryde’s, minke, and blue whales. 
Ø Characterized by torpedo-shaped (fusiform) body, and ventral pleats that increase mouth size while feeding.
Ø Feed by gulping and filtering.
Ø Bowhead, right, and pygmy right whales. 
Ø Characterized by a large, deep bucket mouth and rotund figure.
Ø Feed on krill, and skim through the water to filter out organisms.
Ø Gray whale.
Ø Characterized by feeding on crustaceans stirred up from the seafloor mud.
Ø Feed by vacuuming food through their baleen.
 Note: Odontocetes include Physeteridae (e.g., sperm whale); Platanistidae (e.g., river dolphins); Delphinidae (e.g., oceanic dolphins, killer whales); Phocoenidae (e.g., smaller true porpoises); Ziphiidae (e.g., beaked whales); and Monodontidae (e.g., narwhal, beluga).

Appendix 3 Adaptive Radiation and The Evolution of Cetaceans

The process of one species evolving into many species is called adaptive radiation (also called evolutionary divergence). This evolutionary process occurs slowly over many generations, usually over a period of thousands or even millions of years.

Adaptive radiation occurs when a population of a species becomes divided and each separated sub-group of the species adapts to different habitats and utilizes different food sources, eventually evolving different physical traits that were beneficial in the particular environment.

The evolutionary principal of natural selection dictates that the best fed members of a population are generally the healthiest and produce the most offspring, thus perpetuating their specific traits. Over many generations, new (unique) species evolve.

When the ancestors of whales began to spread through the oceansfrom polar to equatorial waters, from shallow to deep seasthey discovered new food sources and populated new habitats. The separated sub-groups of the population began to change and adapt to their particular environments.

The great diversity of habitats and food sources, along with the processes of natural selection, led to the evolution of dozens of cetacean speciesdolphins, porpoises, and baleen whales.

Pakicetus inachus was the ancestor of all whale species, and swam through the oceans some 50 million years ago. Over a period of about 20 million years, from 50 to 30 million years ago, Ambulocetus gradually evolved into at least 82 different cetacean species.

Today evolution continues, though we may not discern its occurrence during the relatively short span of our lifetimes. Populations of all species slowly evolve as they adapt to changing environments, and the ancient whales lived in far different environments than are found on Earth today.

The humpback whales’ distant ancestors were land mammals that increasingly ventured into the water for food that the land no longer provided. Over millions of years the species became totally aquatic, no longer walking on land at all. Instead the species spent all of its time in the ocean.

Ancient whale populations utilized a variety of different food sources in different ocean environments. These changes led to new physical adaptations, such as a large tail that aided propulsion. New traits continued to evolve to take advantage of new feeding opportunities

Environmental differences led to physical and behavioral changes among the emerging cetacean species. The separate whale populations eventually became distinct from one another—they looked different, behaved differently, ate different food, and eventually became completely different species.

Some of the ancient whales needed to hunt down and attack larger prey, and for this sharp teeth and the ability to swim fast were beneficial. The most successful of these hunters were better fed, and had more offspring than the less successful hunters.

Among these more successful members there eventually emerged more individuals (e.g., dolphins) with physical traits that favored hunting (fast swimmers, strong teeth, etc.).

In a vastly different area of ocean, however, some of the ancestral whales (aquatic mammals) learned to eat smaller prey, such as krill and herring, and among this subgroup, evolution favored the whales with larger mouths. Teeth were not helpful for feeding on small prey, and in some species (e.g., humpbacks) the teeth gradually disappeared as baleen evolved to filter the tiny prey from the water.

Through adaptive radiation, over many millions of years, there evolved at least twelve different species of baleen whales. All of these baleen whales were extremely large and all had mouths perfectly suited for straining tremendous quantities of tiny creatures from the ocean.

Baleen whales needed large areas of ocean to forage for food, and thus became more solitary, though they sometimes utilized group feeding strategies to encircle and capture prey, also learning to use releases of air bubbles from their blowholes to surround and catch prey.

The seasonal nature of the food sources of the large whales also influenced their migration patterns, which eventually tended toward polar waters during summer for feeding, and warmer, tropical waters during winter when mating and birthing occurred.

There are now at least 82 recognized species of cetaceans, including all whales, dolphins, and porpoises. Of these cetacean species, at least 70 are odontocetes (toothed species) and at least 12 are mysticetes (baleen species).

Each of the cetacean species that exists on Earth today is uniquely adapted to its particular environment. The species’ physical and behavioral traits are the products of past and current environmental conditions—environmental changes drive the process of evolution.

These environmental changes on Earth may occur relatively rapidly, as in the case of the asteroid impact about 65 million years ago that decimated dinosaur populations and allowed mammals such as cetaceans to evolve.


Appendix 4

A Brief History of Whaling
 Whaling was an important part of early Eskimo and Native American culture. The whales were usually hunted from canoes using stone harpoons. Records of humans hunting whales extend as far back as 220 B.C., and pictures scratched on stones depict successful hunts. 
 The Basques used rowboats and hand-held harpoons to hunt right whales along the coasts of France and Spain beginning in 1000 A.D., and by the 1500s most of the right whales along Europe’s coasts had been killed. The Basques crossed the Atlantic in search of more whales. 
 The peak period of whaling in the New World was 1560 to 1570, when about one half million gallons of whale oil were produced annually during the five-month season. As early as the 1600s, humpback whales were hunted from Japanese shores. 
 These practices of aboriginal whaling took relatively few whales, and likely had no effect on the overall population. 
 By the 1630s the Massachusetts Bay Colony established a thriving commercial fishing industry off the east coast of North America, leading to whaling in New England waters and then beyond. 
 Right and bowhead whales were soon hunted nearly to extinction. Then gray whales were hunted along the Atlantic coast of North America by the colonists and other whalers who decimated whale populations. This began the period of hunting further offshore for sperm whales. 
 The peak period of Yankee whaling was from 1800 to 1860 as ships traveled the world’s oceans in search of whales. By 1819 American whalers were hunting near the Hawaiian Islands, and by 1822 about 60 whaling ships patrolled Hawaiian seas. The peak year of whaling near Hawai‘i was 1851 when more than 600 ships docked in Honolulu and Lahaina.
 Beginning in the late 1800s and through the 1900s, commercial whalers severely reduced humpback whale populations in all the world’s oceans. Nineteenth century whalers lured the youngest of the whales within range of the harpoons, speared them, and then used the calves as decoys to lure the mother within range of the weapons. 
 Factory ships were built beginning around 1925, allowing whales to be winched up a ramp at the rear of the ship where they were flensed (cut-up). Smaller ships with cannon harpoons caught the whales and dragged them to the factory ship.
 At the turn of the 20th century, huge numbers of humpback whales were killed as a result of improvements in steam-driven whaling ships as well as the Norwegians’ invention of an explosive harpoon. By 1960, the North Pacific humpback whale population was less than 1,000 whales.
 In 1971, the last American whaling company shut down. All of the large whale species were declared endangered and near extinction. In 1973 the Endangered Species Act was passed, and in 1986 the International Whaling Commission placed a global moratorium on commercial whaling.


Appendix 5

Timeline of Hawai‘i’s Whaling Era

On September 29, 1819, the Equator and the Balena became the first whaling ships to arrive in the Hawaiian Islands. The New England ships anchored in Kealakekua Bay where the Balena harpooned a large sperm whale that yielded more than 100 barrels of oil. This began Hawai‘i’s whaling era.

In 1820, the Nantucket whaling ship Maro under the command of Joseph Allen became the first whaling ship to enter Honolulu Harbor. Allen later discovered rich whaling waters off Japan, and soon hundreds of whaling ships headed for the area to exploit the bountiful sperm whale resource.

The Hawaiian Islands, being centrally located between the American west coast and Japan, quickly developed into a major staging area for ships going to and from the newly discovered whaling area. The main Hawaiian ports for the whaling ships were in Honolulu and Lahaina, and many native Hawaiians were recruited to work on the ships.

In 1822, about 60 whaling ships patrolled Hawaiian waters, and the number continued to grow into a shore-based fishery in Hawai‘i that developed specifically to hunt whales. In 1824, more than 100 whaling vessels arrived in the Islands. On May 1, 1823, the Globe, a Nantucket whaling ship under the command of Thomas Worth, arrived in Honolulu. The Globe was later involved in whaling history’s worst mutiny, led by Samuel Comstock.

In October of 1825, the Lahaina home of Reverend William Richards was attacked by the crew of the British whaling ship Daniel. The whalers were angry at restrictions enacted due to missionary influences in the Islands.

In October of 1827, the sailors of the British whale ship John Palmer fired a cannon at a missionary house in Lahaina, Maui due to a conflict between the sailors and the missionaries. In 1828, a total of 159 whaling ships arrived in Hawaiian ports, including 112 in Honolulu and 47 in Lahaina.

In 1832, a total of 198 whaling ships stopped in Hawaiian ports, including 118 in Honolulu and 80 in Lahaina. The whaling industry continued to grow. Honolulu merchant Henry A. Peirce outfitted the Denmark Hill, which was captained by G. W. Cole and became the first whaling ship to sail under the Hawaiian flag.

In 1834, the whaling ship Helvetius, carrying 1,400 barrels of whale oil, wrecked on the reef off Diamond Head. Kamehameha III (Kauikeaouli) sent men to assist, and about 500 barrels of oil were salvaged.

In the 1840s, several companies in Hawai‘i attempted to hunt local whales. At this time, oil from the sperm whale sold for $1 per gallon, and oil rendered from whale blubber, such as from the humpback whale, sold for 30 cents per gallon.

1846 was the peak year for whaling ship arrivals at Hawaiian ports, with at least 596 whaling ships stopping in the Islands, including at least 429 at Lahaina and 166 at Honolulu. In 1851, a total of 220 whaling ships stopped at Hawaiian ports in 1851. Oil from sperm whales fueled the Industrial Revolution.

On November 8, 1852, the death of imprisoned whaler Henry Burns led to a riot by thousands of sailors who set fire to the Honolulu police station. In 1859, 549 whaling ships stopped at Hawaiian ports, including 249 ships arriving in Honolulu, 116 ships arriving in Lahaina, and 184 ships arriving in other ports.

After oil was discovered in Titusville, Pennsylvania in 1859, it became the new source of lubricants for industry, and this marked the end of the heyday of the whaling industry. By this date, whales were rapidly disappearing due to over-harvesting.

In 1868, about 600,000 pounds of whalebone (baleen) and 775,000 pounds of whale oil were transshipped from the Islands. In 1871, north of the Bering Strait, an early Arctic freeze destroyed the North Pacific whaling fleet, including seven Hawai‘i-owned ships.

In 1966, the International Whaling Commission prohibited all hunting of humpback whales in the North Pacific Ocean. The North Pacific population of humpback whales neared extinction, having declined to an estimated 1,000 whales or less. The Hawaiian Islands Humpback Whale National Marine Sanctuary was created in 1997 to provide protection for the species and their habitat.



Humpback Whale Journey:

A Year in the Lives of Humpback Whales

List of Sources for

Humpback Whale Journey: A Year in the Lives of Humpback Whales

Note on Spellings: All words in the text of the book conform to proper Hawaiian spelling and punctuation, however, the source titles that follow are listed exactly as published, and not altered to conform to proper Hawaiian spelling and punctuation (e.g., diacritical marks are not added).

Atlas of Hawai‘i: Second Edition. Honolulu: University of Hawai‘i Press, 1983.

Atlas of Hawai‘i: Third Edition. Honolulu: University of Hawai‘i Press, 1998.

Balcomb, Kenneth C. III. The Whales of Hawaii: including all species of marine mammals in Hawaiian and adjacent waters. San Francisco, California: Marine Mammal Fund, 1987.

Communication and Echolocation. Internet site:, SeaWorld/BuschGardens, 5/13/2001.

Curtis, Paul C. Whale of a time around Kaua‘i: Visitors, boat operators ready for another season of whale watching. The Garden Island, 12/01/2000.

Endangered animals in the Hawaiian Islands. Internet site produced by the US Fish and Wildlife Service:

Eyre, David L. By Wind, By Wave. Honolulu: The Bess Press, 2000.

Jacobs, Francine, and Beath, Mary; Revised for Hawaii by Tom, Allen; Hawaiian translation by Okimoto, Analu. Sea Turtles: No Na Honou Kai. Produced by the Hawaiian Islands Humpback Whale National Marine Sanctuary and the U.S. Fish and Wildlife Service with permission from the Center for Marine Conservation. Honolulu: Hagadone Printing Company, 1995.

Kaufman, Gregory Dean, and Forestell, Paul Henry. Hawaii’s Humpback Whales. Honolulu: Island Heritage Publishing, 1986.

Mate, Bruce R. Watching whale habits and habitats from Earth satellites. Whalewatcher, Summer, 1989, Volume 23, Number 2.

Norris, Kenneth. Dolphin Days. New York: W.W. Norton and Co. 1991.

Oliver, Anthony Michael. Hawaii Fact and Reference Book. Mutual Publishing, 1995.

Payne, Roger. Among Whales. New York: Charles Scribner’s Sons: Simon and Schuster Inc., 1995.

Polynesian Voyaging Society: The building of Hokule‘a1973-1975. Internet site:

Pukui, Mary Kawena, and Elbert, Samuel H. Hawaiian Dictionary: Revised and Enlarged Edition. Honolulu, University of Hawaii Press, 1986.

Pukui, Mary Kawena, and Elbert, Samuel H, with Mookini, Esther T. and Nishizawa, Yu Mapuana. New Pocket Hawaiian Dictionary. Honolulu, University of Hawaii Press, 1992

Ronck, Ronn. Hawaii Almanac. Honolulu: University of Hawaii Press, 1984.

The Audubon Society Field Guide to North American Fishes, Whales, and Dolphins. New York: Alfred A. Knopf, 1983.

The Humpback Whale: The humpback whale is the fifth largest of the great whales. Fact Sheet: Pacific Whale Foundation, Internet site:, 1999.

Whale Anatomy and Physiology. Internet site:, 5/13/2001.

Woodford, James. We should be so lucky. Internet site:, 5/13/2001.

Zoom Whales: All About Whales. Internet site:, 5/13/2001.

Zoom Whales: Primitive whales and whale evolution. Internet site:, 5/13/2001.

Zoom Whales: Whale Anatomy and Behavior. Internet site: http://www.enchanted, 5/13/2001.


The Four Suborders of Marine Mammals:

Cetaceans (whales, dolphins, and porpoises);

Pinnipeds (sea lions, seals, and walruses);

Carnivores (sea otter);

Sirenians (Stellar’s sea cow-extinct, dugongs, manatees).