Sharks

Hawaiian Name: Manō

Indigenous

Sharks have been swimming in Earth’s oceans for about 350 million years, making them one of the most primitive species alive on Earth today.  Worldwide there are currently about 360 known species of sharks, and the biggest of them all is the whale shark.

Around 45 feet (14 m) long but quite gentle, whale sharks are sometimes seen in Hawaiian waters.

 

Pau pele, pau manō.

Consumed by volcanic fire, consumed by shark.

May I die if I don’t keep my pledge.

                                                                        Pukui and Elbert[i]

 

Native Shark Species of the Hawaiian Islands

The Hawaiian word for shark is manō.  In all, at least 41[ii] species of sharks have been seen in Hawaiian waters, but 20 of these are deep-sea shark species. 

Just six shark species are relatively common in Hawaiian waters, and are seen most frequently by divers, fishermen, and snorkelers.  These six of species include:

Ø                  Gray reef shark (Carcharhinus amblyrhynchos)

Ø                  Galapagos shark (Carcharhinus galapagensis)

Ø                  Blacktip reef shark (Carcharhinus melanopterus)

Ø                  Sandbar shark (Carcharhinus plumbeus)

Ø                  Whitetip reef shark (Triaenodon obesus)

Ø                  Scalloped hammerhead shark (Sphyrna lewini)

 

Also seen fairly often is the tiger shark (Galeocerdo cuvieri), which may be more than 20 feet (6 m) long but on average measures 10 to 16 feet (3 to 5 m) long and weighs up to 1 ton (.9 mton). 

The great white shark (Carcharodon carcharias) is only occasionally seen around the Hawaiian Islands.  While some artifacts in the Bishop Museum contain teeth from great white sharks, it is believed the animals were only rarely seen.

 Great white sharks may reach a length of 20 feet (6 m), and more than 5,000 pounds (2,268 kg).  The largest great white shark ever recorded was 39 feet (12 m) long.

One suspected great white shark attack in the Hawaiian Islands involved the disappearance of William Goines off Hale‘iwa, O‘ahu on May 18, 1926.  Two days later a 12-foot (3.7-m) great white shark was caught off Kahuku, O‘ahu.  Goines remains were found inside the fierce predator.

On March 9, 1969, while surfing at Mākaha, O‘ahu, Licius Lee sustained leg injuries when he was bitten by a great white shark, which was identified based on the analysis of tooth marks in the surfboard. 

A whale carcass in the area had likely attracted the shark.  In addition to these attacks by great white sharks, there have been numerous other reliable sightings of the large predators in Hawaiian waters.

On December 8, 2005, shark tour operator Jimmy Hall, who runs a company that allows people to get close to sharks (the people are in an aluminum cage), got out of the protective cage when an estimated 19-foot-long great white shark (Carcharodon carcharias) appeared during an outing off Hale‘iwa, O‘ahu.  The shark was so large that Hall initially mistook it for a humpback whale.

The encounter was captured on video, and is said to be the first footage of a great white shark in Hawaiian waters.  Hall got in the water with the shark and repeatedly touched its fins and tail.  The footage also shows the shark brushing up against the boat.  The great white shark encounter was shown on local and national news networks, and reported in various other news media.

 

Shark Migration

A great white shark tagged by researchers in 2001 swam from a California seal rookery to the island of Kaho‘olawe and then back to California, spending a lot of time in very deep waters. 

The tagged shark, nicknamed Tipfin by researchers because of its missing fin tip, was tracked using a satellite tag implanted in the shark. 

Tipfin was in California on December 9, 2001, near the Farallon Islands at a sea lion rookery.  Tipfin then traveled to the Hawaiian Islands, usually swimming either within 15 feet (4.6 m) of the ocean surface, or much deeper, from 1,000 to 1,500 feet (305 to 457 m) deep.  Great white sharks are known to feed on spinner dolphins in Hawaiian waters. 

The migration patterns of great white sharks have not been extensively researched, but satellite tagging in the coming years should answer many questions.  Researchers theorize that great white sharks may simply be stopping off in Hawaiian waters on their way to the western Pacific from California. 

Since pregnant female great white sharks have only been spotted off Australia and Japan (and not in California waters), the sharks may be giving birth in the western Pacific. 

Around California’s Farallon Islands (where the seal rookery provides feeding opportunities), male great white sharks return annually while the females only return every other year. 

For updates on efforts to place satellite tags on great white sharks, see the internet site: http://www.montereybayaquarium.org/.

 

Shark Anatomy

Sharks have a long upper tail lobe that provides great thrust for sudden bursts of speed.  The wedge-shaped head of many shark species, such as the tiger shark, provides very little resistance on the sides and allows for quick turning.  Shark skin is composed of hard tooth-like scales called denticles, which are extremely abrasive. 

Special plates just behind the retina in the shark’s eye reflect light to super-sensitive cells that enhance vision.  The tapetum lucidum reflects the light, which then passes through the retina’s light receptor cells and is reflected back, doubling the effects of the illumination.  The lens in a shark’s eye is about seven times as powerful as in humans. 

Sharks also have a lateral line down their center that helps detect low frequency vibrations from a distance.  Tiny electric sensors called electroreceptors help sense extremely small muscle movements of prey, even in total darkness. 

Sharks have the highest known electrical sensitivity of any animal, and may sense as little as five billionths of a volt per meter.  They also have an extremely advanced sense of smell, and some shark species can sense as little as one part in ten billion.  Sharks have no vocal cords nor any other apparatus to make sounds.

 

Birthing

Most sharks are ovoviviparous, which means that the female has eggs, but doesn’t actually lay them.  Instead the eggs hatch inside her body.  The gestation period for the eggs is about nine months, and then the shark gives birth to from 10 to 80 baby sharks. 

Some shark species are oviparous (laying leathery-cased eggs) or viviparous (the embryos are nourished by a placenta-like organ).  While most shark species give birth to just one or two pups, tiger sharks may give birth to up to 135 pups at once.  Sharks may live about 30 years, but not much more than 40.

 

Shark Finning

According to the National Marine Fisheries Service, in 1999 there were 87,576 sharks caught by longline fishermen in Hawaiian waters (usually far offshore).  More than 50,000 of these sharks were finned, and then the rest of the shark was thrown back into the sea.  The fins sell for between $18 and $70 per pound.

Hammerhead and tiger shark fins are considered the most desirable, and are sought after as a delicacy (mostly in other countries).  A new federal law that prohibits shark finning in United States waters, and a new state law that prohibits landing shark fins in the Hawaiian Islands, should drastically reduce the practice of finning.

 

Sharks in Ancient Hawai‘i

Sharks played an important role among the ancient Hawaiians, and were considered by some as ‘aumākua, personal or family gods, and sacred guardians and protectors that should be respected and even fed.  Sharks also played a role in myths and legends, as well as Hawaiian history. 

Stephen L. Desha[iii]gives an account of Kekūhaupi‘o battling the niuhi shark (a name given to various shark species) to pass the final test with his lua master.  Kekūhaupi‘o (“the standing [of the] arched hau tree”[iv]) went on to become the trainer and fellow warrior of the future King Kamehameha I.

 

He niuhi ‘ai holopapa o ka moku.

The niuhi shark that devours all on the island.

A powerful warrior.  The niuhi shark was dreaded because of its ferociousness.  It was believed that a chief or warrior who captured this vicious denizen of the deep would acquire something of its nature.

                                                                        (Pukui: 841-91)

 

Shark teeth were the finest cutters of ancient Hawai‘i, and were used to cut designs for kapa (tapa) barkcloth as well as for decorative bases for drums and ipu (Lagenaria siceraria, bottle gourds).  Shark skin was also used for the head covers of hula drums. 

Equilateral triangles in a chief’s ‘ahu ‘ula (feathered cloak) and the complex tattoo motifs of Hawaiian warriors embodied the mana (divine power) of shark teeth.  Shark teeth were also attached to leiomano (shark-tooth weapons). (See Chapter 11, Timeline: 1782, Chapter 11; and Battle #10, Chapter 17.)

 

Shark Attacks in Hawaiian Waters

An average of two to three shark attacks occur each year in the Hawaiian Islands.  Of all the documented shark attacks in Hawaiian waters, just three are thought to have involved Great White sharks.  These attacks occurred in 1926 and 1969 (see above), and 2003 (see below). 

From 1990 to 1997, the Hawaiian Islands ranked second in the nation in number of shark attacks (26 in the Hawaiian Islands, compared to 133 in Florida).  However, the Hawaiian Islands ranked first in the nation in fatalities from shark attacks during this period, with three deaths.  Worldwide, the Hawaiian Islands ranked fifth in attacks and seventh in fatalities. 

Since 1779 there have been more than 117 documented shark attacks on humans in Hawaiian waters.  In the year 2000 there were 79 documented shark attacks worldwide, ten of them fatal (including two in the Hawaiian Islands, neither fatal).

At a popular west Maui snorkeling beach called Olowalu there have been three shark attacks since 1991.  On January 1, 2002, a 35-year-old male snorkeler about 100 yards offshore was bitten on the buttocks. 

On October 18, 2000, a 56-year-old female snorkeler about ½-mile (.8 km) offshore was bitten on the upper and lower back.  On November 6, 1991, a 41-year-old woman who owned an oceanfront Olowalu home was killed by a tiger shark, prompting the formation of a Shark Task Force as well as a state-sanctioned shark hunt. 

In 1992, shark attacks caused two deaths, both in waters off O‘ahu.  On July 3, 1993, a 16¼-foot (5-m) tiger shark was caught in O‘ahu’s Kāne‘ohe Bay.

The recent history of shark attacks in the Hawaiian Islands includes three attacks in 1994 (two on O‘ahu and one on Kaua‘i); three attacks in 1995 (one each on Maui, Kaua‘i and O‘ahu); four attacks in 1996 (three on Maui, one on O‘ahu); two in 1997 (one on Kaua‘i, one on O‘ahu); and six attacks in 1999 (two on Maui, one on Kaua‘i, three on Hawai‘i Island). 

In 2000 there were two shark attacks on Maui.  One of these resulted in death, and the others resulted in severe cuts, some with critical injuries.  In 2001 there were 76 shark attacks worldwide, including four in Hawaiian waters.[v]

 

A Log of Recent Hawaiian Shark Attacks

Ø                  On November 26, 1991, a 41-year-old woman who owned an oceanfront home on Olowalu on Maui was killed by a tiger shark as she swam about 100 yards (91 m) offshore near her home, prompting the formation of a Shark Task Force as well as a state-sanctioned shark hunt.[vi]

Ø                  On February 19, 1992, a male was bodyboarding west of O‘ahu’s Waimea Bay at a spot known as Leftovers and did not return to shore.  The next morning his bodyboard was found with a large piece missing.  The 16-inch crescent taken out of the bodyboard was presumably due to a shark bite.[vii]

Ø                  On November 5, 1992, a male bodyboarder offshore on O‘ahu’s Wai‘anae coast died after being bitten on the right leg by a shark estimated to be about 11 feet (3.4 m) long.[viii]

Ø                  On October 28, 1997, a young man who is also a champion bodyboarder lost his lower right leg to a shark at the surf spot known as Majors along the coastline of the Pacific Missile Range Facility.  He was about 150 yards (137 m) offshore when the attack occurred.  His right hand, which he used to fight off the shark, was also injured and suffered nerve damage.[ix]

Ø                  On March 5, 1999, a woman suffered a 13-inch shark bite to her leg as she was swimming off Ka‘anapali.[x]

Ø                  On March 18, 1999, two honeymooners kayaking off the Lahaina coast were apparently blown out to sea.  The man was rescued three days later on Kaho‘olawe. He told authorities that their boat capsized and a shark killed his wife.[xi]

Ø                  On August 15, 2000, a windsurfer was severely bitten in the lower left leg by a tiger shark.  The attack occurred about ½-mile offshore southeast of Kū‘au after the windsurfer fell off his board and was severely bitten in the lower left leg by a tiger shark identified by teeth recovered after the incident.[xii]

Ø                  On October 18, 2000, a 56-year-old female snorkeler about ½-mile (.8 km) offshore was bitten on the upper and lower back. 

Ø                  On March 23, 2001, a man suffered minor cuts when he was bitten by a shark while bodyboarding at O‘ahu’s Sandy Beach about 35 yards (32 m) offshore.

Ø                  On April 11, 2001, a man received cuts and puncture wounds to his left hand when he was bitten at O‘ahu’s ‘Ewa Beach by a shark estimated to be about 2¾ feet (84 cm) long.

Ø                  On November 14, 2001, a surfer at Maui’s Kapalua Beach had his surfboard bitten into by a shark.

Ø                  On January 1, 2002, a 35-year-old male snorkeler about 100 yards offshore was bitten on the buttocks. 

Ø                  On March 25, 2002 a bodyboarder lost his lower left leg to a shark about 150 feet (46 m) offshore at Brennecke Beach on Kaua‘i’s south shore.  The 17-year-old was pulled underwater twice, and then finally freed after he jabbed the eye of the shark (thought to be a tiger shark).

Ø                  On August 28, 2002 in O‘ahu’s Kewalo Basin channel, a tiger shark, estimated to be 11 to 12 feet (3.4 to 3.7 m) long, bit into the left foot of a 16-year-old boy, causing a large gash.  The shark also bit the tail off the boy’s surfboard.

Ø                  On September 27, 2002, a man was surfing off O‘ahu’s Kāhala Beach when his surfboard was bitten by a black tip shark estimated to be 4 feet (1.2 m) long.

Ø                  On October 30, 2002, a 62-year-old woman, swimming about 25 yards (23 m) off of Kama‘ole Beach Park 1 in Kīhei on Maui’s south shore suffered deep wounds on her right foot (cutting ligaments, tendons and an artery) in what is suspected to have been a shark attack.

Ø                  On November 17, 2002, a 33-year-old woman visitor from San Diego, California was severely bitten by a shark about 100 yards (91 m) off of Maui’s Kā‘anapali Coast.  She suffered wounds to her wrist, forearm and right shoulder.  She stated that the shark was gray, with a white-tipped tail, and the shark was definitely more than 6 feet (1.8 m) long.

Ø                  On May 10, 2003, on Hawai‘i Island a man swimming near Kahalu‘u Beach when an estimated 6-foot-long, gray-colored shark bit into his left foot, ankle, and calf.

Ø                  On June 24, 2003, a man’s foot was bitten by a shark as he swam offshore at Mākua Beach in Wai‘anae on O‘ahu.  The man had been swimming with a pod of about 45 spinner dolphins, when the dolphins suddenly (and rapidly) left the area just before the man’s foot was bitten.

            The shark may have been preying on the dolphins, and mistaken the man for a dolphin.  Based on the man’s opinion that the shark was about 5 feet (1.5 m) wide and silver colored, and the account of the fleeing dolphins, experts deduced that it was a likely a great white shark.  Fortunately the man’s foot was not severely damaged despite needing more than 25 stitches.

Ø                  On October 5, 2003, a woman was bitten by a gray-colored shark estimated to be about 4½ feet at Maui’s Kalama Beach while wading by a fishing net.  She received injuries to her right index finger, right knee, and left thigh.

Ø                  On October 31, 2003, a 13-year-old girl on Kaua‘i’s north shore lost her arm to a large tiger shark.  A nearly 14-foot- (4.3 m-) long tiger shark caught a few days later is believed to have been responsible for the attack.

Ø                  On April 7, 2004, a man surfing in murky waters at a spot called “S-Turns” about 250 yards offshore of Pōhaku Park in Kahana was killed by a shark. 

            The man was bit in the upper thigh, suffering a 14-inch wound.  Two people paddling out to surf heard the man yelling for help and provided assistance, but the victim died from loss of blood as he was being brought to shore.[xiii]

Ø                  On October 9, 2004 a 34-year-old O‘ahu man who was spearfishing was bitten on the left shoulder and face by an estimated 12-foot shark in murky waters outside Kūpeke Fishpond in southeast Moloka‘i.  He saw the shark as it approached him head on. 

            The victim had caught some fish and they were trailing behind him attached to a cord about thirty feet long.  “I remember this big force hitting me,” he recalled, “and this big shadow wrapping me up, and I remember just being shaken.” 

            As the shark returned the man hit it with his uncocked spear gun, and the shark swam away.  Quickly losing blood, the victim used his wetsuit to help stop the bleeding.  The wound was exacerbated, doctor’s said, by the “...shaking action of the shark’s clamped jaws.”[xiv]

Ø                  On February 16, 2005, a man surfing on O‘ahu’s north shore was struck from below by an estimated 8-foot-long tiger shark.  The incident occurred about 40 yards from Rocky Point at Sunset Beach. 

            The shark hit the board so hard it knocked the wind out of the surfer, who then tried to swim away while kicking at the shark.  The man was able to get back on his surfboard and get to shore safely.  After the attack the beaches were closed from Sunset Beach to Pipeline.[xv]

Ø                  On May 2, 2005, a man surfing in Maui’s Kū‘au Bay was knocked off his surfboard by a shark that bumped into his ankle and bit into his board.  Surfing the spot commonly known as Noriega’s, the man was about 200 feet offshore when the incident occurred, and he saw “...a shark’s gray head, about 18 inches wide, gnawing on the board.”

            Hammerhead sharks had been seen birthing in the area two days earlier, but it remains unsure what type of shark bit the man’s board.  The 7-foot-10-inch surfboard was left with six tooth marks.[xvi]

Ø                  In October of 2005, an eight-foot (2.4 m) shark jumped from the water and bit the board of a surfer, then proceeded to thrash the board back and forth as the surfer struggled to stay on.  The surfer then hit the shark in the nose and attempted to push the shark away.  The shark let go and left.[xvii]

Ø                  On December 21, 2005, a swimmer was attacked by a shark losing his pinkie finger and the top of his ring finger and the side of the palm of his hand.  The attack occurred about 400 yards off of Keawakapu Beach on south Maui.  The victim saw the shark come up from below, and noticed its gray surface and white stomach.[xviii]

      (For more information about these shark attacks and other attacks (e.g., barracuda, jellyfish) in Hawaiian waters, see Chapter 15: Incidents of Disaster and Survival in the Hawaiian Islands.)

 

Avoiding Shark Encounters

To avoid shark encounters, surfers and swimmers are well advised to avoid river mouths, especially after rains, and avoid murky waters.  Also avoid being in the water at dawn and dusk as well as during the nighttime hours when some shark species may come inshore to feed.

Do not go in the water if you are bleeding or have any open cuts.  Sharks are extremely sensitive to very low concentrations of blood and other body fluids.

Shiny jewelry and other high contrast items are also considered potentially attractive to sharks.  Avoid excessive splashing, and always swim with someone else.  If you are unsure, always swim at beaches with lifeguards and feel free to ask for advice.

 

What Sharks Eat

A shark control program from 1967 to 1969, and a shark catching program in 1976 examined the stomach contents of 281 tiger sharks.  The 1976 study found that the smaller sharks, those 6 feet (1.8m) long or less, preferred bony fish (e.g., puffer and porcupine fish), and also eels, with some squid, crab, and birds.  Sharks often catch birds that are sitting on the water’s surface. 

The study found that medium-sized tiger sharks also ate lots of bony fish, but medium-sized sharks ate more lobsters, turtles, dolphins, goats and sheep as well as other sharks.  The stomach contents of sharks more than 10 feet (3 m) long included fish, sharks, rays, lobsters, birds, turtles, octopi, and squid. 

In addition, 16% of the 135 sharks that were 10 feet (3 m) long or larger had mammal remains in their stomach.  These mammal remains were mostly dolphins, but also dogs, rats, mongoose, and goats.  One shark had human remains in its stomach! 

An ancient Hawaiian proverb states, “Ho‘ahewa na niuhi ia Ka‘ahupāhau.” (“The man-eating sharks blamed Ka‘ahupāhau”), meaning “Evil-doers blame the person who safeguards the rights of others. Ka‘ahupāhau was the guardian shark goddess of Pu‘uloa (Pearl Harbor) who drove out or destroyed all the man-eating sharks.”[xix]

 

New Technologies to Protect Against Sharks

The risk of being bitten by a shark in Hawaiian waters is relatively small, and shark bite incidents are relatively few compared to the millions of people who swim and surf in Hawaiian waters each year without any encounters.  Nevertheless, some people would be more confident with some protection. 

Researchers have now developed an electric transmitter that emits an electromagnetic security field around divers, and has been shown to repel sharks.  Soon the cautious water enthusiast may wish to carry this extra protection, just in case.

[Photograph: Shark]