I miss pea crabs.

As a New Jersey native who once worked on an oyster boat, finding dime-sized, pea crabs in a newly opened oyster was a daily occurrence that presented a challenge. Who could we get to eat the soft-shelled, still crawling critters? 

Back then I usually demurred, but now, living with a French chef and having a more adventurous palate, I would love to find these little crustaceans for a special snack. After oystering much of the winter and voraciously consuming so many of those bivalves, I realized that I hadn’t seen a pea crab even once.

Turns out, you can find pea crabs here, though we are at the northern range of the ones that hang out in oysters, so we find them less often than in states south of here. And furthermore, those oyster pea crabs are more likely to be hiding in wild bivalves that live on the ocean floor, rather than in the pond-dwelling shellfish that I had been harvesting.

Other varieties of pea crabs do find shelter in our waters or, more precisely, in other animals in our waters. Considered commensal (where one partner benefits and the other neither is harmed nor benefits) by some and parasitic by others, these crustaceans are cohabitators or, more accurately, squatters, who are definitely not welcome by commercial shellfishers.

There are pea crabs that live in the gills of bivalves (oysters, mussels, clams, and scallops), others that dwell in subsurface marine worm cases (and grow so big that they can’t get out), ones that lodge in the burrows of mud snails, reside with sea urchins, sand dollars and sea squirts, and even inhabit the rectum of sea cucumbers.

Life in those deep, dark places has made pea crabs what they are today. They have adapted well. A soft shell is sufficient, since these crabs are already protected by their host’s hard shell or other body parts. Their eyes are small and somewhat useless as they live a light-less existence. Their light color and translucence that resembles their hosts is the result of them eating the same foodstuff. In bivalves, pea crabs live in their mantle, on their gills filtering out floating planktonic matter brought in by the host’s siphons.

Pea crabs start off as floaters too. As tiny, free floating plankton, they get into their host via those same siphons, but stay and start to grow, eating as the host eats. Typically, it is the larger female found inside these shells, not being able to get out after they grow to a certain size. Males are much smaller and can come and go, entering to fertilize the female crab’s eggs, then moving on.

Humans encounter pea crabs most often when consuming wild shellfish, mostly to their confusion and chagrin. Restaurants and raw bars remove them when they find them, often throwing pea crabs away and wasting a culinary curiosity.

It wasn’t always this way. In an early twentieth-century seafood cookbook, there were 16 recipes for pea crabs — one requiring 500 of the little ones — and a 1913 New York Times article called them an “epicure’s delight.” They get rave reviews from some wild food lovers, when buttered and sauteed or lightly coated and fried.

In the end, it doesn’t matter whether you like your pea crabs cooked or tossed into the shell pile — you have a choice. Not so much for these crabs’ hosts because even as their landlord, they don’t have the option of evicting these crafty crustaceans.

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown, and author of Martha’s Vineyard: A Field Guide to Island Nature and The Nature of Martha’s Vineyard.