Ocean Watch

Monday, July 14, 1997

Barracudas dangerous
but rarely attack humans

Last week, I saw an enormous barracuda in the Ala Wai Boat Harbor. Usually the barracudas I see in the harbor are babies, less than a foot or so long. This one was so big, though, that, even though I was in a hurry, I had to stop and stare.

Except for an almost imperceptible stirring of the fins to keep its body stationary, the 3-foot-long fish lay motionless near the surface. Several young manini (convict tangs) darted in and out of rocks nearby.

Brave manini, I thought. Or more likely, the barracuda's "I'm-just-a-floating-stick" act was working well.

I watched for awhile but didn't see the big fish strike. The one time I did see a barracuda catch a fish, it happened with such swiftness that I couldn't make out any of the details. A little fish was there; the barracuda jerked; the little fish was gone.

Barracudas eat both large and small fish, striking with lightning bursts of speed. Unlike some fish predators, barracudas can't expand their mouths to swallow large fish whole. To eat big prey, barracuda slash them to pieces with remarkably sharp teeth. A large barracuda can cut a mature parrotfish in two pieces with a single bite.

Hawaii hosts two species of barracuda: the great barracuda or kaku (Sphyraena barracuda) and Heller's barracuda or kawelea (Sphyraena helleri).

Kaku, the great barracuda, are the ones we see in the Ala Wai Harbor. These fish are active during the day, using camouflage to catch fish. Juvenile kaku almost always live in sheltered inner reefs and harbors. Adults can live in these places too, but large barracudas usually head offshore to hunt in the open ocean.

Individual kaku can grow to nearly 6 feet long and weigh up to 100 pounds.

Heller's barracudas are active at night, forming schools near the reef during the day. This smaller species grows to about 2 feet long.

Is it reasonable to be afraid of barracudas? Like sharks, the answer is usually no. Of the 22 barracuda species found throughout the world, the great barracuda is the only one known to attack humans. The risk of being bitten by this fish, however, appears extremely low. In a study of 29 reported barracuda attacks in the United States between 1873 and 1963 (90 years), only 19 were confirmed.

Barracuda attacks have occurred in Hawaii. Two Maui fishermen were bitten in separate incidents in the 1960s.

A 6-foot-long barracuda slashed the leg of one man who was throw-net fishing. The resulting injury to his left foot and leg required five hours of surgery. The second man needed 255 stitches to repair arm wounds.

In the late 1980s, a barracuda attacked a scuba diver at an isolated rock offshore from Kailua. The resulting wound was minor.

In Kailua-Kona, doctors treated two women in separate incidents for barracuda bites to the scalp. Both women were wearing shiny barrettes in their hair at the time of the attack. One, bitten in the 1990s, required surgery to remove embedded teeth.

Because barracudas have two parallel rows of sharp, cutting teeth in both upper and lower jaws, bites can cause deep, slashing cuts, often causing nerve and tendon damage and sometimes severing large blood vessels. Also, barracuda teeth can break off inside wounds.

Some theorize that barracuda attacks occur when the predator mistakes a human for prey. Because a barracuda may view the flash of jewelry or camera equipment as a silvery fish, removing jewelry and avoiding murky water may reduce the chance of a bite.

Usually, barracudas keep their distance from swimmers and divers.

The greatest threat barracuda pose to humans is ciguatera, a poison these fish sometimes carry in their flesh. Ciguatera poisoning comes from eating affected fish.