You would never think that Jan Riley was trigger-happy.

She is a gentlewoman to the core, no Annie Oakley here. It was not a gun that gave her the itchy finger, nor the brief but insistent call of hunting season.

As a frequent and inquisitive observer of nature, Jan was intrigued by an unfortunate fish — unfortunate because it had met its end on Fuller street beach in Edgartown. The gulls must have been having their way with the carcass, as it was missing its eyes and other soft sections.

Jan knew right away that this wasn’t any old fish. Luckily her finger was not too twitchy to use her computerkeyboard. With an eye for detail and the help of Google, she identified the fish inquestion as a grey triggerfish.

Triggerfish are more common south of these parts. Though their range is often stated as extending from Florida through Nova Scotia, they are seen here in New Englandinfrequently. If you observe this occasional visitor, you won’t quickly forget it.

The distinctive look of the triggerfish can be described as short and stout. These oval-shaped fish are laterally compressed, so they appear thin and narrow when seenhead-on. More prominent in the face-to-face sighting would be its teeth, large and sharp incisors found in a very small mouth that literally crush the competition (and prey).

These insistent incisors allow the triggerfish to snack on some seriously solid stuff. Triggerfish can eat sand dollars, shellfish, sea urchins and even barnacles — all very crunchy critters — by seeking out their soft spots and diving into dinner. 

Having such an advantage is great for finding food, but the triggerfish also needs a trick to avoid predators. As weak swimmers, their ability to evade an enemy comes not so much from speedas from technique andtrigger. This is how the fish earns its name.

A triple-spined dorsal fin is just the thing! Normally the dorsal fin is tucked away against the fish’s body. The dorsal fin can be extended vertically, acting like an anchor to allow the triggerfish to hide in the cracks and crevasses of coral reefs and rocky bottoms. Or that extended dorsal fin with its sharp spines might intimidate predators, dissuading the many that seek triggerfish tapas.

To accomplish this trick, the trigger fish must extend the second, or trigger spine of its dorsal fin, which will lock the first (and longest spine) vertically. Only when the second spine is depressed can the first retract and allow the entire fin to fold down.

Though the triggerfish may be able to elude some of its predators, many will still find their way to becoming a super supper. At the top of the fish’s predator list (and the food chain) are humans. Triggerfish are known to be a superb eating fish, though learning how to clean and skin the fish could be achallenge. After all, it didn’t get the aliases of “filefish” and “leather jacket” for nothing! 

Those that master the skill will find that triggerfish are fabulous smoked, salted or fried. One warning, though, should be offered: triggerfish are a species that can cause ciguatera fishpoisoning. Ciguatera is an illness that is the result of eating fish that contain toxins produced by the marine algae Gambierdiscustoxicus. There is no cure for ciguatera toxins, and symptoms are ver y unpleasant.

So though the taste of this fish may be terrific, the result of eating one could be repulsive. Thus, the triggerfish should trigger caution, if not avoidance. For those that insist, they can join Annie and get their (spear) gun.

 

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.