Thursday, May 24, 2012

Horseshoe Crabs!

I'm back from our week-long adventure in Florida, and there will be posts about the trip soon to come. But first, I have to make a quick Connecticut-related diversion, because look what was emerging from the ocean when I went to Silver Sands State Park this afternoon:

Mating Horseshoe Crabs!

There were several pairs of these creatures scattered along the shoreline, the smaller male clasping on to the larger female, ready to fertilize the eggs she lays in the sand. Apparently, Horseshoe Crabs come up to reproduce in late spring at high tide, so I guess it was just lucky that I happened to be at the beach at the right time. These are such crazy, cool creatures!

A few lone Horseshoe Crabs (actually more closely related to spiders than crabs, as Wikipedia tells me... weird!) somehow ended up on their backs on the beach, waving their legs around in the air:

I don't know if these Horseshoe Crabs were nearing the ends of their lives anyway, but I flipped them back over just in case they weren't. (Have I mentioned that Horseshoe Crabs are big, and much heavier than I expected? I needed two hands to maneuver these things, and it felt a bit like picking up a flattened, wriggling bowling ball.) This one seemed glad for the assistance, at least, as it dragged itself back into the ocean:

Soooo cool! I'm glad I got to see these creatures up close.

And here's a bonus picture from today's beach visit -- a bunch of Barn Swallows seem to have nests under the boardwalk, and one of the birds landed right next to me to twitter at its fellows:

Pretty bird. :)


  1. Very cool! Seeing these photos brings back great memories of finding horseshoe crabs on the beach in Georgia when I was doing programs for school groups. Kids loved them once I convinced them they didn't have stingers in the tails.

    1. Yeah, the tails do look a little menacing until you know they're safe. These creatures are pretty awesome!

  2. There will be more spawning during the next full moon (June 4), and that will pretty much be it for this year, although there will be stragglers. They'll come in on the night high tide, since the darkness is safer for them. The waves turn them over and they can often right themselves, but if they get trapped as the tide goes out, it is a good thing to help them out by turning them over. Use two hands and use the shell, not the tail. Technically called a telson, the tail is NOT dangerous, as Rebecca correctly notes, but handling the tail CAN harm the animal. Wrongly considered primitive, horseshoes have elaborate neural sensory systems, (their compound eyes have long been studied to understand the neurological and chemical nature of vision, including human vision) and their tails help them tell day from night.

    A keystone species to the littoral habitat up and down the East Coast. Fascinating creatures, and unknown to most people, they are commercially bleed to extract Limulus amoebocyte lysate (LAL), which is used to test all pharmaceuticals and medical devices for bacteria. Everybody who's been in a hospital or even taken a course of antibiotics have the horseshoe crabs to thank. Unfortunately, we thank chopping them up them into bait.

    1. Thanks for the very informative response, Matthew! Don't worry, I flipped them over carefully and didn't grab them by the tail.