I wrote about the Atlantic horseshoe crab, Limulus polyphemus last week, before I got a chance to head out to the city shore to look for some this year. So that was theory, this is practice, at Plumb Beach.
And practice can be hands-on. If you should happen to see a horseshoe crab wrong-side up and obviously still kicking, be a good sport and turn it over. They are absolutely harmless to you, so don’t be afraid of them. Don’t use the telson, or tail, however, which is very delicate and easily damaged (it’s got sensors to tell day from night); just use two hands on the outer edge of the main part of the shell (the helmet-like prosoma) and turn it over.
Note the slipper shells, Crepidula fornicata, hitching a ride.
And on top, barnacles as well as slipper shells. Another of the crabs had a cluster of blue mussels growing on it. Plowing through the sand of the littoral, and further out at sea, the tank-like bodies are home to many other species.
That’s the mouth right there in the center. This is a female, since it’s lacking the modified pedipalps/hooks that the male has instead of a first pair of walking legs.
That’s the smaller male on the back attempting to do his ancient duty. He grabs on with his pedipalps.
You may want to open this image up for a better view. I think that’s a horseshoe crab nest there in the upper middle of the image. After laying her eggs, the crab then looped the loop on the lower right, and headed back to the sea.