caught crab sea of cortez stanford biology cruise gillyEditor's Note: William Gilly, a professor of cell and developmental biology and marine and organismal biology at Stanford University, is traveling with a group of students on board the Don José in the Sea of Cortez. They will monitor and track Humboldt squid and sperm whales in their watery habitats. This is the group's sixth blog post.


SEA OF CORTEZ—[Cue: Theme music from Superman or Mission Impossible]


We found the Sally Lightfoot tangled and twisted in a mess of abandoned fishing line, its little claws waving in distress from behind a rock. The charismatic crab, Latin name Grapsus grapsus—which is also pretty fun to say—had become ensnared along with a dozen or so sea urchins. We did not know when it happened, but judging from the looks of it, and the seven or eight complicated knots it had managed to tie itself in, the helpless critter seemed to have been there for quite a while. Its powerful pinching claws, though well-adapted to eat and defend, had not yet found a way to cut through a human's 60-pound fishing line.


From the moment my classmate Lauren and I saw it struggling, we felt compelled to help Sally. The rescue seemed simple enough: do with scissors what it could not do by itself. Like Jacques Cousteau rescuing a pelican or a beached baby whale, we wanted to save a life and help solve the problem of human-induced environmental degradation with this one symbolically kind gesture toward all of ocean-kind.


But even after our hard work and pinched fingers, first in swimming the crab back to the boat and then in untangling it, our mission didn't end quite as planned. The crab grabbed the scissors we used to free it and decided not to let go. It didn't seem to know we were trying to help.


caught crab sea of cortez stanford biology cruise gillyHowever, once on the back deck and in the water, the Sally Lightfoot suddenly released the scissors and began falling slowly backwards, spiraling down into the grey-blue abyss. Its brilliant colors submerged into murky particulate debris and plankton until it was nothing but a forlorn, somersaulting white blob. Gone were the deep reds and blues of its claws and body. Gone were the little hints of green and purple in its eight strong multi-jointed legs. It was an intriguing and darkly comical sight watching this animal the size of a fist fall into something so immense.


Our rescue team watched the sinking crab worriedly and with great disappointment. We had wanted to release it back safely into the wild and then pat ourselves on the back for a job well done. We were hit with the consequences of having just lost this intertidal crab to an alien environment for which it was not adapted. That is to say, for a crab that tends to spend most of its day above water blowing bubbles on the rocky shore, the ocean bottom was a harsh place full of mighty predators. If Sally weren't eaten by some hungry fish on its way down, chances were good that it would be dinner for a giant sea star or another larger, more hostile crab.  Without Sally's above-water agility and bursts of speed, which delighted both Charles Darwin and John Steinbeck, our crab was out of its element. Think James Bond trying to pay his taxes or do his laundry.


This crab tragedy has been a crash course in addressing some of the most nagging questions confronting any scientist, especially fledgling ones like myself. By solving problems and investigating the world around us, are we helping or hurting things? Does turning over rocks or tromping around in tide pools irreparably disturb the way things are? What about weighing the consequences of catching and dissecting heaps of squid in order to investigate climate change and sustainable food sources?


We worried about the fate of our Sally, but our classmates assured us that even if this crab had come to an unsightly end, we had at least potentially saved dozens of future crabs from the fishing line we had picked up. We took a holistic perspective and considered what was of ultimate importance. To quote Steinbeck and Ricketts's Sea of Cortez:


"Let us go...into the Sea of Cortez, realizing that we become forever a part of it; that our rubber boots slogging through a flat of eelgrass, that the rocks we turn over in a tide pool, make us truly and permanently a factor in the ecology of the region.... And if we seem a small factor in a huge pattern, nevertheless it is of relative importance. We take a tiny colony of soft corals from a rock in a little water world. And that isn't terribly important to the tide pool. Fifty miles away the Japanese shrimp boats are dredging with overlapping scoops, bringing up tons of shrimps, rapidly destroying the species so that it may never come back, and with the species destroying the ecological balance of the whole region. That isn't very important in the world. And thousands of miles away the great bombs are falling and the stars are not moved thereby. None of it is important, or all of it is."


Epilogue

To get to the bottom of my lingering curiosity about the fate of our lost crab, I have begun respiration experiments to learn if Sally Lightfoot can breathe just as well underwater as on land.  In the next week, I hope to understand more about crab respiration in general, but will probably leave with more questions than I answer. But what I have already realized is that wonder and curiosity make up the backbone of marine invertebrate science, and science in general. Small failures simply lead to more questions and an increased sense of wonder.


Images courtesy of Lauren Lindsmayer