Scalloped Hammerhead Shark

Photographs and comentary by

Rico Leffanta

My first experience with a shark was a surprise to both of us. I was standing in the surf watching reef fish when I saw a baby hammerhead near my leg. I thought it was a children's toy and picked it up.

The hammerhead in the photo below was cruising the reef by the Hawaiian Hilton Village on Labor Day, 2000. It was only about 1.3 metres in length but, once again, seemed to be a Walt Disney toy rather than a predator. Those beautiful eyes so precariously perched out where the slightest brush against the coral could damage eyesight, and that soft, pliable skin would, I'm sure, delight any child who hasn't seen Jaws!

As I have only encountered these two sharks in Hawaii, it is more likely tourists will be attacked by jellyfish than a shark in Waikiki (Jelly fish are so beautiful the Japanese keep them in aquariums)( in Waikiki, jellyfish usually do their thing 7-10 days after the full moon).

In fact, Marine Biologist Susan Scott claims that there are only THREE reported hammerhead shark attacks on humans in Hawaii since 1779!

However, Year 2000 (the oriental "Year of the Dragon") was a record for shark attacks in Hawaii, which usually average only 2-3 per year. Possibly the increasing number of people in the water leave sharks less space to frolic without encountering humans.

When most people encounter a shark, the only question on their mind is, "How do I get out of this?" The answer may depend upon asking yourself the following questions BEFORE you go in the water:


On July 27,2002, this young snorkler caught an even younger baby hammerhead shark in front of the Hilton Hawaiian Village. This is as small as they get, so it was a first encounter for both of them, and both will certainly be giving the future further consideration!

Not much is known about shark behaviour because it is a challenge for researchers to take notes underwater, or under attack!

Scalloped Hammerhead sharks are notorious for swishing about, doing corkscrews, etc., but no one knows for certain whether that is just shark aerobics, or part of a mating ritual which has changed very little since it was first described by the Marquis de Sade.

There is no doubt that sharks are seeking some oral gratification, so a possibility exists that sharks mistake surfers and swimmers for potential mates.

Imagine yourself as a teenage shark searching the underworld for a mating opportunity when - lo and behold - a shimmering female shadow beckons on the surface; up you zip to nibble a little fin but instead discover some surfer's arm or leg hanging in your mouth.

Like children who get a plastic doll at McDonald's and then discover the arms and legs fall off, most sharks abandon the surfer and carry on searching for true love, but some sharks are like that typical brat who screams, "You tricked me, you (expletive: rascal" Ronald") and I'm gonna get you good!" and then batters the doll to bits.

Shark history is millions of years longer than surfer history, so sharks instinctively know they musn't leave one little shred of evidence behind because, if discovered, for the next forty years other sharks would taunt them with, "Hey, look! There's Dum Dum Shark! He can't tell the difference between a surfboard and a female!" every time they pass by.

Such mistakes can happen because, like surfers, scalloped hammerhead sharks also like to hang loose, hovering near the surface, endlessly waiting for The Big One. This habit gave the Hawaii Institute of Marine Biology the unique opportunity to become the first biologists to document suntanning in lower vertebrates.

The HIMB study revealed melanin content in hammerhead sharks increased by 14% over 21 days, and doubled to 28% over 215 days, so it could be that sharks are just checking out tan lines, or perhaps - like tourists and surfers everywhere - just searching for a really good remedy for a painful sunburn.


Anyone with a surfboard can answer that question! Sharks can detect scent or sound of prey from about 2 miles (3+km) away but, like surfboards, sharks have no brakes!

Like surfers - or children riding scooters or a bicycle without brakes, the solution is to circle down until you can stop where you want. This also gives sharks an opportunity to identify, study, plan, and come to grips with their prey.

Scalloped hammerhead sharks can NOT see directly in front, so if your eyes were where your ears are, you would quickly see the advantage in circling your dinner (and everyone would thank you for circling before you parked your car).


Why snack when you can eat steak?

Hammerhead sharks have never been observed feeding on anything but surfers and swimmers during daylight hours, but a recent study by the Hawaii Institute of Marine Biology mostly found snapping shrimp in the bellies of an abundant population of of juvenile scalloped hammerhead sharks in beautiful Kaneohe Bay (also populated by U.S. Marines), on the island of Oahu, in Hawaii.

HIMB researchers were surprised to find their sharks only ate about 1% of their (?) body weight each day (the report did not reveal whether that 1% belonged to a researcher, a snapping shrimp, a Marine, or another shark).

Stomachs of adult scalloped hammerhead sharks, in Hawaii, reveal an appetite for bony fish - especially needle fish, eels, squid, octopus, shrimp and lobster, a diet which clearly establishes hammerhead sharks are using their heads to find food, much the same as French pigs use their snouts to find truffles.


Academics have long believed the hammerhead shark came into being when some prehistoric, disgruntled shark teenager tried to look different from all the other sharks and banged his head against the wall a few times just to attract attention, but the teenage mutant theory was discredited by DNA tests indicating hammerhead sharks were indeed an original creation.

In shark culture, the scalloped hammerhead shark is immediately identifiable by five dents in the front rim of its skull. Most people don't like to get close enough to make that observation, but it is commonly seen in large, overbearing females (females are genetically larger than male hammerhead sharks).

Scalloped Hammerhead sharks can outmaneuver (and consume) other sharks, so Academics have long held the belief that having a flat head - with eyes where ears should be - gives Hammerhead sharks an advantage over other sharks, i.e., the head shape promotes an hydroplane lift, enabling hammerhead sharks to make sharper turns than other sharks; eyes and nostrils positioned at either side of the head also give hammerhead sharks a distinct advantage in tracking prey.

In fact, Hammerhead sharks butt heads like billy goats, which they certainly would NOT do if their eyes were out there in front looking at what they were doing!

We now know all organisms generate an electrical field, and the Scalloped Hammerhead shark's head works just like a metal detector or a marine mine detector, it scans an area for electrical impulses of organisms. Hammerhead sharks also use their heads to pin down prey until they can sink their teeth into it.


Academics are mystified by the tendency of hammerhead sharks to form large schools. Although there is an unending list of reasons why this could be, none has been established as gospel.

A school of 100+ scalloped hammerhead sharks is about as attractive as going to Columbine High School, yet those who dropped into a shark school report that most of the in-crowd appear to be females and youngsters looking to make a name for themselves. That doesn't sound much different than a typical Native American Indian Pow Wow, i.e., a social get-together where singles can see what and where their prospects are, and match-makers can employ those arts to perpetuate the species.


Your mother-in-law is probably fond of horses because horses can NOT regurgitate; the scalloped hammerhead shark CAN regurgitate - and it does, so beware!


On March 25, 2002, 17 year-old track star, Prom King and Fire Dancer Hokuanu Aki was hanging loose on his surfboard at Brennecke Beach, Kauai, when a shark bit his left foot and pulled him under. Caught completely by surprise and breathless, Hokuanu lived up to his name ("Hoku=star, anu=cool/cold"), and played it cool by following safety instructions by first tearing at the shark's gills, but to no effect. Hokuanu then tried pounding his fist against the shark's nose but, again, to no effect. In a last ditch effort, Hokuanu stuck four fingers in the shark's eye and gouged it out; then the shark let go, and Hokuanu made it to shore where good fortune awaited him in the form of Nancy Roberts, a visiting nurse from Littleton, Colorado, who provided first aid until an ambulance arrived.

It worked for him; will it work for you?

Incidentally Hokuanu's surname is Aki, the Hawaiian word for, "To take a bite and let go". Feeling that lucky?

On Halloween, 2003, a shark bite took 13-year-old Bethany Hamilton's left arm off to the shoulder. She survived because (a) she went surfing with a friend and (b) she kept her wits about her. Being bitten by a shark did not dissuade Bethany from surfing; ten weeks later, she finished fifth in a surfing contest, and said she expects to do much better after she masters getting up on her surfboard with one hand (Jack Palance had DECADES to learn how to do one-arm pushups, Bethany is already a winner after only ten WEEKS!).


More interesting is the story of how it was named. American history books never report the native version of events, so you probably don't know that when Captain Cook arrived in the "Sandwich Islands" and found the natives were friendly, he invited some of the Hawaiians aboard the Bounty. One of the guests was a little Hawaiian girl named Alohalani, whose mother had become friendly with a member of the crew, a Welshman from Ynyswbwl named Dai Jones (aka "Jones-the-Spy").

Alohalani was very bright, and quickly learned to speak English (albeit with a Rhondda Valley accent). Alohalani learned that the English called a toilet "the loo" to honour the Sun King, Louis XIV of France, because it was the only place in the civilised world where the sun didn't shine. So when Captain Cook was having difficulty explaining the definition of "bounty" to Hawaiians, Alohalani happened to look down the marine toilet, see three hammerhead sharks, and piped up, "Its three in the loo, isn't it?"

By the time Captain Cook got a look, only one scalloped hammerhead shark was there to be seen. Because Alohalani could not make the "th" sound very well, the shark was recorded as, "Sphryna lewini" which was Cook's phonetic spelling of "'s free inna loo in i?"

Naturally, neither Englishman, Welshman, nor American was about to let history reveal a woman - especially a native girl - had anything to do with the conquest of the New World, so the credit was given to Uncle Lew, a white man who could be relied up to keep his mouth shut for a price.

Students should remember the academic term for a Scalloped Hammerhead Shark is "Sphyrna lewini", but give all the credit to Uncle Lew on tests, otherwise your teacher will give you an "F" which is a British, Welsh, and American abbreviation for: "Fat chance you have of graduating from this class!"


The future may look bright when one heads the food chain, but looks are deceiving. Just like a school bully, true friends are in short supply.

Approximately 100,000 tons (2,000 metric tons) of sharks are caught in Hawaiian waters every year, and another 150 metric tons are brought to Hawaii from other Pacific locations. Of this total, about 86% are killed only for their fins (believed by some people to be an aphrodisiac) and, like the great American bison (buffalo) - the remaining carcass is discarded.

The meat of the other 14% is eaten fresh, fresh frozen, dried, salted or smoked for human consumption, the shark's skin becomes some leather product, its teeth are sold to collectors, the cartilage and oil for vitamins are sold to the do-it-your-self health market, and anything left over is intended to keep your pussy purring.

Perhaps "shark" deserves a another definition!

If you prefer to keep some glass between you and hammerhead sharks, the Maui Ocean Center in Ma'alaea opened a 50,000-gallon display of Mano Kihikihi (scalloped hammerhead sharks) on 18 January 2004.