Yesterday's Lesson

Although I am preparing to move on from fishing in order to continue my formal education in marine science, this isn't to say that I'm not still learning from Cap every day on the boat.

Yesterday my lesson was on urchins, those spiny little kelp-eating pin cushions of the sea. Cap used to be an urchin diver, so he knows a lot about them. He lights up when he talks about his urchin-diving days, before they were overfished. My impression is that it was his favorite profession of the many jobs he's had in his life.

We hauled a trap in deeper water that came up with a few small urchins in it. I commented that the spines looked longer on these urchins than I recalled seeing. Cap said that urchins grow longer spines in deep water where it served them well to "catch" algae. In shallow water, where you see them foraging on kelp blades, they have plenty of sustenance. Therefore, their spines are shorter, since food is abundant. This makes a lot of sense when I think about it. Algae is more plentiful in shallow water due to the availability of light that fuels photosynthesis. However, only the shorter wavelengths of light (blue) penetrate to greater depths of the water column, so algae is less common. The urchins have probably adapted to deep water by growing long spines with which they can catch algae that drifts and sinks to the bottom. I found this tidbit of information fascinating.

Late in the day we caught another urchin that was perhaps three inches in diameter. It was in shoal water and, sure enough, the spines were shorter. Cap asked if I like to eat the roe and I eagerly answered "yes." I ate it for the first time last summer when we were diving in Stonington in waters teeming with urchins. It is the sweetest product of the ocean that I've ever eaten. There's no doubt why it is such a prize delicacy. I didn't know how to open the urchin so Cap cut a circle out of the top for me. When he popped it open, the gonads were small, shriveled, and brownish indicating that it wasn't "ripe." The roe is at it's peak when the gonads are swollen and bright orange. I'm sure there are certain times of year when urchins are at their reproductive peak and it's better to eat the roe, like many other sea creatures.

I dissected and examined the internal anatomy of the small echinoderm for a while as Cap steamed to the next buoy. I could see the inside of the feeding structure: a round apparatus with teeth imbedded in it for grazing on algae. A brown tube emerged from the center of the circular "mouth" and connected to a little sack that I guessed was the stomach. Little green flakes floated around, probably partially digested algae.

The ocean and its creatures continue to amaze me. It is a realm constituting two-thirds of this planet and yet so little is known about it still. As the human population grows, I believe that the sea will be an increasingly important source of protein. I strive to learn more about it and to explore ways with which we can harvest and grow seafood. I hope to contribute someday to discovering how we can sustain or at least supplement our diet with seafood while simultaneously respecting the ocean's finite resources.