Seabirds of the Hawaiian Islands

Seabirds of the Hawaiian Islands

Seabirds of the Hawaiian Islands 

Noddy Terns (Noio Kōhā)

The Great Frigatebird (‘Iwa)

Laysan Albatross (Mōlī)

Pacific Golden Plover (Kōlea)

Newell’s and Wedge-Tailed Shearwaters

(‘A‘o; ‘Ua‘u Kani)

Red-Tailed and White-Tailed Tropicbirds

(Koa‘e ‘Ula; Koa‘e Kea)

Overview of Hawaiian Seabirds

About 9,700 species of birds inhabit Earth, but only about 3% of these species are marine birds. The Hawaiian Islands have at least 22 species of native seabirds, which combine to form a total population of more than 12 million seabirds in the Hawaiian Islands. Most of the Hawaiian Islands’ seabirds live on the Northwestern Hawaiian Islands, which are hundreds of miles northwest of the eight main Hawaiian Islands.

[Photograph: Seabird over the ocean]

‘Au i ke kai me he manu ala.

Cross the sea as a bird.

To sail across the sea. Also applied to a hill that juts out

into the sea or is seen from far out at sea.

(Pukui: 237-28)


 

Hawaiian Noddy Tern (Anous tenuirostris melanogenys)

Hawaiian Name: Noio Kōhā

Status:

[Illustration: Noddy tern]

More than 60% of seabirds in the Hawaiian Islands are noddies and terns, and there are three native species of each. Noddies are actually a type of tern, but are distinguished from other terns by their distinctive nodding and bowing behavior during mating ceremonies.

Noddies are seabirds, but they lack substantial oil glands at the base of their tails, so they cannot alight on the water for more than a few minutes. Noddies and terns present a fish to their mate during mating ceremonies. A male noddy will nod and bow when he feeds his mate before she lays her egg.

Ua ho‘i ka noio ‘au kai i uka, ke ‘ino nei ka moana.

The seafaring noio bird returns to land, for a storm rages at sea.

A weather sign.

(Pukui: 2787-307)

Black noddies have yellow-orange legs and feet, and vary in color from dark gray-brown to sooty black. They live throughout the year along the coasts of the main Hawaiian Islands as well as throughout the Northwestern Hawaiian Islands.

Black noddies build substantial nests on rocky ledges, in caves, or in trees. They may live to 25 years of age.

Brown noddies nest on the ground, usually laying a single egg near ground vegetation. Brown noddies are found in the Northwestern Hawaiian Islands as well as on the offshore islets of the main Hawaiian Islands.

[Photograph: Noddies bowing]


 

The Great Frigatebird (Fregata minor palmerstoni)

Hawaiian Name: ‘Iwa

Indigenous: Tropical Pacific.

To look up and see a frigatebird soaring overhead is like stepping back into the age of dinosaurs. With a forked tail and bent wings, the frigatebird looks like an ancient pterodactyl in flight.

Frigatebirds are also called “man-o’-war birds,” a name given to them by sailors who thought they resembled the favorite pirate vessels known as frigates.

There are five kinds of frigatebirds in the world, but the only type of frigatebird in the Hawaiian Islands is ‘iwa, also known as the great frigatebird. A wide-ranging species, frigatebirds banded in the Hawaiian Islands have later been seen in the Philippines.

An ancient Hawaiian saying states: He ‘iwa ho‘ohaehae nāulu.” (An ‘iwa that teases the rain clouds.”), which refers to A beautiful maiden or handsome youth who rouses jealous envy in others.”[i]

[Illustration: Frigatebird (wing profile)]

Anatomy

The great frigatebird’s body may average 43 inches (109 cm) long with a wingspan that may exceed 90 inches (229 cm), yet the bird usually weighs less than 3 pounds (1.4 kg).

The female frigatebird is bigger than the male. Females are black with some white feathers on the upper breast and throat, while males have all black feathers.

Male frigatebirds have an inflatable red pouch of skin under their throat, and they often blow up this throat (gular) pouch like a balloon, particularly when they are near a colony of birds and want to get a female’s attention.

Frigatebirds can glide for several hours with very little effort, often soaring at heights above 500 feet (152 m), higher than any of the other seabirds in the Hawaiian Islands. This is helpful since they have very little webbing between their toes, and don’t land on the water if they can avoid it.

Lacking oil glands to waterproof their feathers, frigatebirds don’t dive beneath the ocean’s surface for fish like some other seabirds.

Feeding

Frigatebirds can dive very fast and make sharp spiraling turns, and are probably the most acrobatic of all of Hawai‘i’s seabirds. Frigatebirds may chase and dive down upon other seabirds, such as red-footed boobies and shearwaters, in order to force them to drop or disgorge their food.

The frigatebird then uses its agility and speed to swoop down and catch the food before it hits the water. This piracy explains how the frigatebird got its Hawaiian name, ‘iwa, which means “thief.”

In addition to stealing food from other seabirds, frigatebirds fly low over the water and use their long, hooked bills to grab floating food, including squid, fish, newly hatched sea turtles, and even mālolo (flying fish).

Frigatebird Nesting

Frigatebirds are migratory, traveling between their nesting areas and places where food is more plentiful. Though frigatebirds are commonly seen flying over the Kaua‘i shoreline, they do not nest there. Most of Hawaiian frigatebirds nest on the Northwestern Hawaiian Islands, which begin hundreds of miles northwest of Kaua‘i.

Frigatebirds are seen near in the Northwestern Hawaiian Islands during winter months, and are seen on the main Hawaiian Islands more often in summer. Frigatebirds are also known to nest on Ka‘ula Island, which is about 22 miles (35 km) southwest of Ni‘ihau and also on Mokumanu (“Bird Island”[ii]), off of Mōkapu Point on the east side of O‘ahu.

Frigatebirds are biennial breeders, nesting every other year beginning at about five years of age. In breeding season the males gather together and show off their puffed up red throat pouches. The birds gather nesting material (branches and twigs) to build relatively flat nests in bushes or other vegetation.

Nesting material is gathered primarily by the female frigatebirds, but it’s primarily the male that builds the nest. The female then lays one white egg around March or April. Male and female frigatebirds take turns incubating the egg, which basically means that they sit on it. After about 1½ months, the chick hatches.

The baby chick has no feathers at first, and so the parents must protect the baby from the sun. Soon the hatchling is covered with white, downy feathers. The baby gets fed by the adults about every 18 hours and stays in the nest about 4½ months before it grows adult feathers and fledges (learns to fly), which usually occurs in October. Frigatebirds have been documented to have reached 34 years of age.

Some ancient mariners kept frigatebirds on their ships. The sailors knew that when a frigatebird was released it would fly straight toward land, helping the sailors know which way to go. Frigatebirds feathers were also utilized in ancient Hawaiian featherwork.

[Photograph: Frigatebird, red throat pouch]


 

Laysan Albatross (Diomedea immutabilis)

Hawaiian Name: Mōlī

Indigenous: Central and North Pacific.

Along the oceanside cliffs of the Hawaiian Islands, adult albatross perform elaborate courtship dances with each other. Then they breed, nest, lay their eggs, and nurture their young. Quite a site to see, fat and fluffy baby albatross are sometimes bigger even than their parents.

Eventually the albatross parents leave, and the young ones must learn to fly on their own. Finally the fledglings head out to sea, not to return until years later when it is their turn to nest.

[Illustrations: Albatross mating dance; baby albatross.]

Physiology, Migration, Feeding and Nesting

The Laysan albatross may be nearly 3 feet (91 cm) long with a wingspan up to 80 inches (2 m). Adult Laysan albatross weigh from 5 to 7 pounds (2 to 3 kg), making them the largest seabirds in the entire Pacific region.

Laysan albatross are white, with black on their upper wings and around their eyes. This black coloration around the eyes is a common trait in seabirds, and helps to reduce glare.

Albatross may live for more than 40 years, and may stay at sea up to five or more years before returning to land to nest. The birds often spend the summer months about 1,000 miles (1,600 km) or more from the Hawaiian Islands, on and over the waters of the North Pacific Ocean.

Laysan albatross do not dive beneath the water, but instead fish from a sitting position on the surface. This makes them particularly vulnerable to shark attacks, which occur quite frequently in the birds’ Northwestern Hawaiian Islands habitat.

Laysan albatross usually arrive in the Hawaiian Islands by late October or early November, and stay at their nesting areas until June or July. Even during the nesting season they may fly thousands of miles in search of food, then return directly to their island nests to feed their young. Laysan albatross feed mostly on large squid as well as the eggs of the mālolo (flying fish).

As graceful as Laysan albatross are in flight, they are fairly awkward on land. Laysan albatross sometimes have difficulty taking off for flight unless they can run down a slope or use some other suitable launching area. Once in the air, however, Laysan albatross can soar for hours without flapping their wings, and may even sleep while airborne.

Laysan albatross prefer to nest in the same area where they were born, often returning to the exact same location. They also tend to mate with the same partner for life. The female lays one egg in a nest depression, usually in November or December.

The parents alternate tending the egg, which incubates for about 64 days, and then the chick may take several days to break free from the shell. After about 5½ months the chicks fledge (learn to fly).

During the nesting season in the Hawaiian Islands, albatross often perform bizarre courtship dances that include prancing around with their mate and thrusting their beaks skyward along with bill snapping and vocalizations.

These courtship displays, as well as the difficulty the chicks have learning to fly, are likely reasons for the birds’ nickname: “gooney bird.”

Endangered Status

Worldwide, many types of albatross are endangered due to hunting. Early explorers utilized their meat, oil and feathers. In just one 17-year period, more than five million albatross were killed for their downy body feathers, which were used as stuffing for quilts and mattresses sold in European markets. Also highly valued were the albatross’ long white tail feathers and wing feathers, which were prized for pen plumes.

Laysan albatross nest on the main Hawaiian Islands, particularly on O‘ahu, Ni‘ihau and Kaua‘i, though many of their traditional nesting areas no longer provide good habitat because they have been developed.

Still the birds persist in some areas near where homes and other structures have been built. The albatross remain particularly vulnerable to domestic animals (e.g., cats and dogs) that pose a continuing threat to the birds (especially to baby albatross).

On Kaua‘i, Laysan albatross have been making a comeback, particularly at Kīlauea Lighthouse National Wildlife Refuge on the island’s north shore, and at the Pacific Missile Range Facility on Kaua‘i’s southwest shore.

Most albatross in the Hawaiian archipelago are found on the Northwestern Hawaiian Islands, a group of reefs, islets and atolls located hundreds of miles northwest of Kaua‘i.

At the far northwest of the Northwestern Hawaiian Islands are the French Frigate Shoals, Midway Atoll and Kure Atoll, which are home to the largest albatross populations of the Hawaiian Islands.

Midway Atoll has the largest Laysan albatross population anywhere, with nearly 400,000 nesting pairs. Midway also has nearly 20,000 black-footed albatross (Diomeda nigripes) and there are occasional sightings of the rarely seen short-tailed albatross (Diomedea albatrus), which is federally listed as an endangered species. The short-tailed albatross is also known as the golden gooney because of its yellow head and neck feathers and its pink bill.

As of January 2001, there were an estimated 1,150 short-tailed albatross remaining worldwide, making them one of the world’s most endangered seabirds. The species main breeding area is Torishima Island off Japan. One short-tailed albatross banded at Torishima in 1993 was spotted years later at Midway.

Satellite Tagging of Laysan Albatross in the Hawaiian Islands

In 1999, ornithologists working in conjunction with Kīlauea Point National Wildlife Refuge and the U.S. Fish and Wildlife Service attached transmitters to Laysan albatross nesting near Kīlauea Lighthouse on Kaua‘i’s north shore.

When the birds left Kaua‘i to find food for their young, the transmitters sent signals to a satellite that relayed the birds’ latitude and longitude data back to Earth.

Results from a previous study based on Tern Island found that one albatross flew 24,843 miles (40,000 km) in just 90 days. The bird traveled all the way across the North Pacific and back, a distance equal to flying all the way around the world.

Another bird made repeated trips east to the San Francisco Bay area and then back to the Hawaiian Islands to feed its young. Continuing research will reveal more about the large, graceful albatross birds, including their unique courtship habits and their amazing journeys in search of food.

Updates on tagged birds may be seen on the internet site: www.wfu.edu/albatross.

[Photograph: Albatross]


 

Pacific Golden Plover (Pluvialis fulva)

Hawaiian name: Kōlea

Indigenous.

Pacific golden plovers migrate to the Hawaiian Islands during fall to feed, then return north to Alaska again for the summer months to lay their eggs.

This is similar to the migration habits of koholā (Megaptera novaeangliae, humpback whales), which also come from Alaska to spend their winters in the Hawaiian Islands. The humpback whales, however, come to the Hawaiian Islands in winter to mate and give birth, and go north in the summer to feed.

An ancient Hawaiian proverb, “O Kā‘elo ka malama, kāpule ke kōlea,” (“Kā‘elo is the month when the breasts of the plovers darken,”) refers to “...the month when the plovers are fat and ready to fly on their migration to the north.”[iii]

[Illustration: Pacific golden plover]

The Pacific golden plover’s non-stop flight between Alaska and the Hawaiian Islands may cover more than 3,500 miles (5,633 km) but take less than three days.

After spending May, June, and July on the Alaskan tundra, the plovers head south in August (some arrive in July). The plovers often arrive in flocks that disperse once they reach the Hawaiian Islands.

While plover adults usually begin arriving in the Hawaiian Islands in late August, juveniles arrive in late September, staying until late April, or May, when they again head north.

Anatomy and Physiology

Pacific golden plovers are about 11 inches (28 cm) long, weigh about ½ pound (.23 kg), and live to about eight years of age. Plovers are dark brown, and spotted with gold on top, but paler on the underside. Plovers have a large, dark eye region, and a fairly large head relative to their body.

Before leaving the Hawaiian Islands in April, the female plover molts into a beautiful beige-gold breeding plumage. The male plover gets a “tuxedo” look, with a pure white stripe along the sides of the head and down the neck. The abdomen, breast, cheek and throat are black.

Feeding

Pacific golden plovers are known to return to the same general area each year to feed, often returning to the same specific patch of grass, where they will remain throughout the season. They prefer open grassy areas, including pastures, lawns, and golf courses.

In the Hawaiian Islands the plover is very territorial, and will defend its feeding area against other plovers, though it will often ignore other bird species. Some plovers move around a bit more, and are not as territorial when it comes to their feeding grounds.

During its winter stay in the Hawaiian Islands, the plover feeds on insects and other invertebrates, as well as certain flowers and leaves. Plovers often run in short bursts, intermittently stopping to look for insects. Feeding for about four months in the Hawaiian Islands, plovers fatten up for the long journey north.

Migration

Beginning in late April, the plovers head north again to the Alaskan and Siberian tundra, a journey that may span over 3,500 miles (5,633 km). Plovers are often very solitary birds during their stay in the Hawaiian Islands, but before they begin their migration north they gather together in large flocks and then head north.

The departure dates may be quite regular among certain Hawaiian Island plover populations. For example, the O‘ahu birds are said to always leave within days of April 25, but this may vary.

Once the plovers begin their journey north, they may sustain speeds of 60 to 70 miles per hour (97 to 113 km/hour), making them among the world’s fastest birds when it comes to sustained level flight, which excludes speeds attained by diving birds such as raptors.

During their migrations, plovers fly at elevations up to 20,000 feet (6,100 m). With a tailwind, the birds may reach speeds of over 100 miles per hour (161 km/hour), and the flight to the northern breeding grounds may be completed in 50 to 60 hours.

Some plovers may remain in the Hawaiian Islands during the summer months. New efforts to track plover migrations, estimate population size, and learn more about plovers are being coordinated through the website: www.hawaii.edu/bird.

The Hawaiian Pacific golden plover population is currently estimated at about 2,500 birds. Plovers have also been seen in South Pacific Islands, and these plovers may be migrating much farther than the birds that winter in the Hawaiian Islands.

Nesting

Once plovers reach their arctic nesting grounds, the males build nests and share in the duties of caring for the chick. Most but not all males change partners from year to year.

Plovers typically lay four, greenish-brown eggs (one every other day). Together the eggs total about two-thirds of the female’s body weight, and may be more than 50% yolk, which is a higher percentage of yolk than the eggs of most other birds. The plover’s nest is lined with lichens and leaves. The eggs are incubated by the female at night and the male during the day.

Less than a month after hatching, the downy goslings and ducklings begin to fledge (learn to fly). In early August the parents begin to leave, but the chicks will not follow until one or two months later.

This next generation of plovers must then find their way to the remote Hawaiian archipelago thousands of miles away. The journey south will be the beginning of a cycle of migration that will then be repeated each year.

[Photograph: Plover]


 

Shearwaters—Newell’s and Wedge-Tailed

[Illustration: Newell’s and wedge-tailed shearwater]

Newell’s (Townsend’s) Shearwater (Puffinus auricularis newelli)

Hawaiian Name: ‘A‘o

Endemic subspecies

Status: Threatened subspecies. Found on Kaua‘i, O‘ahu, and Hawai‘i Island.

The Newell’s shearwater, a local variety of the Townsend’s shearwater, has a black back, a white breast, and is about 13 inches (33 cm) long, with a wingspan that may exceed 3 feet (91 cm).

Newell’s shearwaters breed on the Hawaiian Islands from April to November, flying to their nesting colonies each day at dark and leaving again before dawn. The sound they make is a repeated “ah-oh,” which explains their Hawaiian name, ‘a‘o.

An ancient Hawaiian saying states: “He ‘a‘o ka manu noho i ka lua, ‘a‘ole e loa‘a i ka lima ke nao aku.” (It is an ‘a‘o, a bird that lives in a burrow and cannot be caught even when the arm is thrust into the hole.”), which was “said of a person who is too smart to be caught.”[iv]

Newell’s Shearwaters spend about six months over the eastern tropical Pacific, and then in April they return to their mountain nesting sites, which are frequently in areas with dense uluhe ferns (Dicranopteris linearis).

There they dig new burrows (or fix up their old ones), and then nesting occurs. The sounds of the birds above the colonies at night have been described as similar to the sounds of crying babies, mules, or even ghoulish laughter.

Shearwaters are seabirds that skim close the surface of the ocean and then plunge into the water to catch fish or squid spotted from the air. The birds have what is called a tube nose at the base of their beak. The tube nose is connected to a gland that removes extra salt from the bird’s food and water. Shearwaters sometimes stay at sea for years, and their webbed feet allow them to kick off from the water’s surface.

The fish and squid that shearwaters feed on are often pushed toward the ocean’s surface by schools of tuna. Fishermen have long known that seeing a gathering of shearwaters may be a sign of the valuable tuna species the fishermen seek.

[Photograph: Newell’s shearwater]

Wedge-Tailed Shearwaters (Puffinus pacificus chlororhynchus)

Hawaiian name: ‘Ua‘u Kani

Indigenous (migratory).

[Illustration: Wedge-tailed shearwater]

Wedge-tailed shearwaters are the most commonly seen Hawaiian seabird offshore of the main Hawaiian Islands.

Wedge-tailed shearwaters are about 18 inches (46 cm) long, with a wingspan of about 3 feet (91 cm) and a wedge-shaped tail. They are brownish-gray, have a pointed beak and webbed feet. Birds in the “light phase” (most Hawaiian shearwaters) are dark on top but whitish-colored underneath.

Wedge-tailed shearwaters nest in burrows on the ground. The burrows are small little caves about 2 to 3 feet (60 to 90 cm) long. The shearwaters begin preparing their nests in April and lay a single white egg in June.

Each parent sits on the egg for about ten days at a time as the other parent feeds at sea. After about 52 days the chick hatches (usually in August), and both parents feed the nestling partly digested food (regurgitated squid and fish).

About two weeks before the chick learns to fly, the parents leave the nesting island. The chicks must then survive on their own stored fat. The young bird soon learns to fly and then is able to get its own food.

Shearwaters are often called “the moaning birds” because they make strange wailing or crying sounds when they are settled in their colonies, particularly at dawn and dusk.

The literal translation of the wedge-tailed shearwater’s name, ‘ua‘u kani, is “calling ‘ua‘u,” which describes the sound made by the bird. The shearwaters’ habit of gliding so close to the surface of the water that they appeared to slice or cut it caused English sailors to name the bird “wedge-tailed.”

Wedge-tailed shearwaters arrive at the Hawaiian Islands around March. Like the Laysan albatross, the wedge-tailed shearwaters return to the same location where they were born to lay their eggs. The chicks hatch in July or August, and after about 3½ months the chicks learn to fly.

By November the shearwaters migrate along the equatorial countercurrent to the coast of Central America, reaching such disparate locations as Panama and Japan and sometimes staying at sea for up to four years. Many of the birds migrate back to the Hawaiian Islands in March, repeating their migration path each year.

Shearwater Populations

Archaeological evidence shows that ancient Hawaiians utilized shearwaters and petrels as a food source. Abundant remains of shearwaters have been found in ancient Hawaiian settlements.

Pigs and dogs brought by the early Polynesian settlers of the Hawaiian Islands also had an effect on the populations of the ground nesting shearwaters.

After Westerners arrived, cats and mongoose further decimated the shearwater population. By 1931 the birds were thought to be extinct in the Hawaiian Islands, but they were “rediscovered” in 1954.

Saving the Shearwaters

Every autumn many of the little fledgling Newell’s shearwater birds leaving their colonies and head for the sea where they will feed on their own for the first time.

During this maiden journey, the birds often become disoriented by bright lights near roadways and other areas, causing them to become disoriented and land. This leaves the birds vulnerable to cars as well cats, dogs and other predators. These incidents are known as strandings.

On Kaua‘i, residents have been saving these stranded birds for more than 20 years. Most shearwater strandings occur in October and November. The peak period of the month for strandings is during the new moon when the sky is dark.

Also vulnerable to strandings due to nighttime light are other night-flying seabirds, including the ‘ua‘u (Pterodroma phaeopygia sandwichensis, Hawaiian dark-rumped petrel) an endangered species.

The Kaua‘i Island Utility Cooperative has recently completed work on all of its 3,049 light poles on Kaua‘i, installing a housing that blocks the light from escaping upward. This was recommended by island’s Save Our Shearwater program. Other night-flying seabirds are also vulnerable to

Shearwater Aid Stations

On Kaua‘i, the public is encouraged to rescue stranded shearwaters and leave them in small, protected cages that are provided at special aid stations. These aid stations are located at Kaua‘i County Fire Departments as well as other locations.

The birds placed in the cages at the aid stations are picked up each morning by state and federal wildlife biologists. The birds are checked for injuries, banded, and then released along the shoreline so they may fly out to sea. Up to 2,000 Newell’s shearwaters (an estimated 90% of all strandings), are returned to safety each year, with more than 25,000 birds rescued to date. Hundreds of fledgling wedge-tailed shearwaters are also rescued.

Rescuing Shearwaters

Be careful when attempting to rescue stranded shearwaters, as the birds may occasionally bite. Often the disoriented birds will be found sitting on the ground, and it will not be too difficult of a task to relocate them to an aid station. Stay clear of the bird’s head as you grasp its folded wings and tail. Then put the bird in a ventilated box for transport.

The Department of Land and Natural Resources (DLNR) advises the public that stranded birds may have unseen injuries and should not be tossed up into the air in an attempt to allow them to fly.

Local residents may assist in helping the native bird species survive by reducing unnecessary outdoor lights, especially floodlamps, which may cause the birds to land due to temporary blindness.

[Photograph: Newell’s shearwater in burrow]


 

Tropicbirds

White-Tailed Tropicbird (Phaethon lepturus dorotheae)

Hawaiian Name: Koa‘e Kea

Indigenous: Tropical Pacific.

Red-Tailed Tropicbird (Phaethon rubricauda rothschildi)

Hawaiian Name: Koa‘e ‘Ula

Indigenous: Tropical Pacific.

[Illustration: Red-tailed and White-tailed Tropicbirds: Comparison]

You will see them high in the sky, their long, thin bodies effortlessly soaring above the ocean or over mountain valleys. The red-tailed tropicbird and the white-tailed tropicbird are both almost all white in color, except the red-tailed tropicbird has a red bill and red tail feathers, while the white-tailed tropicbird has a yellow bill and white tail feathers.

At 36 to 42 inches (7.6 to 107 cm) long, the red-tailed tropicbird is a bit larger than the white-tailed tropicbird, which is 23 to 32 inches (58 to 81 cm) long. Both types of tropicbirds plunge dive into the water to catch fish and squid, and both birds may give a loud scream-like sound while in flight.

An ancient Hawaiian saying states: “Ke koa‘e iho ia, he manu lele no ka pali kahakō.” (That is the tropic bird, one that flies at the sheer cliffs.”), which was “said of a person who is hard to catch.[v]

[Illustration: Tropicbirds soaring.]

The red-tailed tropicbird has a 44-inch (112-cm) wingspan, compared to the 36-inch (91-cm) wingspan of the white-tailed tropicbird. Red-tailed tropicbirds also have two long, red tail feathers as well as black feathers around their eyes.

White-tailed tropicbirds have black eye stripes black bars across their wings and back, and long, white tail feathers. The distinctive long tail feathers of the tropicbirds, also called streamers, are actually highly specialized inner tail feathers.

Extremely graceful in flight, red-tailed tropicbirds are awkward on land, and barely able to walk without falling. This is due to the their fully webbed feet. Tropicbirds plunge dive into the ocean to catch fish and squid, sometimes going as deep as 10 feet (3 m).

Feathers from both the red-tailed and white-tailed tropicbirds were utilized in ancient Hawaiian featherwork. The feathers were utilized to make royal feather standards called kāhili, consisting of feather clusters attached to long poles. Kāhili were symbols of chiefly rank. Especially valued for kāhili were the tail feathers of the red-tailed tropicbird.

Breeding

Tropicbird breeding extends from March to October. Red-tailed tropicbirds are known for their elaborate displays of courtship during flight. The birds sometimes repeatedly circling each other in an upward and backwards flight motion.

A bird engaged in this backward flight appears a bit like it is rowing a boat, and may be nearly stationary in wind during this elaborate courtship dance, which usually lasts less than ten seconds.

The red-tailed tropicbird lays its eggs on the ground, usually under a shrub, beach vegetation or a rock overhang. The white-tailed tropicbird may nest inland and along the coastline, and lays its egg on a crater wall or on a ledge on a steep cliff face. The chicks of both birds are fully feathered after about six weeks and by about two months of age they learn to fly.

Tropicbirds are commonly seen near Kīlauea National Wildlife Refuge on Kaua‘i’s north shore, and circling high above Kaua‘i’s Nāpali Coast and Waimea Canyon. The birds are relatively rare, however, on the other Hawaiian Islands. On the island of Hawai‘i, tropicbirds are seen at Hawai‘i Volcanoes National Park in Kīlauea Crater. On O‘ahu the birds are sometimes seen on the windward side of the Pali.

[Photograph: Side by side comparison photos of red-tailed tropicbird and white-tailed tropicbird]



[i] p. 73, Pukui, Mary Kawena. ‘Ōlelo No‘eau: Hawaiian Proverbs & Poetical Sayings. Honolulu: Bishop Museum Press, 1983. Proverb 645.

[ii] Pukui, Mary Kawena, Elbert, Samuel H., and Mookini, Esther T. Mookini. Place Names of Hawaii: Revised & Expanded Edition. Honolulu: University of Hawaii Press, 1974.

[iii] p. 262, Pukui, Mary Kawena. ‘Ōlelo No‘eau: Hawaiian Proverbs & Poetical Sayings. Honolulu: Bishop Museum Press, 1983. Proverb 2399.

[iv] p. 64, Pukui, Mary Kawena. ‘Ōlelo No‘eau: Hawaiian Proverbs & Poetical Sayings. Honolulu: Bishop Museum Press, 1983. Proverb 545.

[v] p. 188, Pukui, Mary Kawena. ‘Ōlelo No‘eau: Hawaiian Proverbs & Poetical Sayings. Honolulu: Bishop Museum Press, 1983. Proverb 1749.