Great barracudas are a fish I see every once in a while when I’m snorkeling. They’re generally about two feet long, with a somewhat menacing look, and a languid swimming style. They tend to keep their distance, easing away until they melt into the distance, which is fine with me since they’ve been known to attack humans.

Recently, I was snorkeling at a regular spot and approaching a shallower area where I usually find a variety of reef fish. I spotted the fish above from quite a distance. It was hanging motionless in the water. As I closed in I could see that this barracuda was huge, twice the size of any I’d seen previously in both length and girth.

I wanted to get closer for a photo, but I was also wary. Previous barracudas that I’d seen had looked capable of inflicting a nasty bite. This one looked like it could remove a limb. I snapped a few photos as the fish drifted out toward deeper water. Then it swished its tail and vanished at warp speed.

John Hoover says that great barracudas “grow to about 5½ feet, but are usually half this size in Hawaii.” I’d estimate this one was around four feet long, so a big one for these waters. (The yellow tang just behind it is probably six to eight inches long.) He also notes that “large individuals tend to increase in girth rather than length,” which was certainly true in this case.

In my attempts to identify what I see in the water, I use John P. Hoover’s book The Ultimate Guide to Hawaiian Reef Fishes, Sea Turtles, Dolphins, Whales, and Seals. His website is hawaiisfishes.com.