Saturday, October 24, 2009

Just the Facts, Ma'am

I went to a lecture, mini-hike at a relatively new and not very large Audubon Sanctuary about 8 or 10 miles away the other day. The slide show covered a lot of ecology of the area including some things I did not know about the horseshoe crab. [see Chengis beclow] It is not really a crab; it's an ancient animal -- was around 230 million years ago, so it can be called a living fossil. It's more closely related to ticks and scorpions than crabs.

In my picture of Dad and the Boys, Dad may be Mom because the females are larger than the males. They can get to be as much as 24 inches across and can live to 40 or so, and as they get older they get darker. I've seen a few on the beach, maybe 15 inches across, a deep brown almost black; maybe still growing. I had no idea! These beasties shed their shell. Many that I find are just discarded shells, although often I find the animal is decaying inside so it ran afoul something or other. In North America the horseshoe crabs are found from the Gulf of Mexico up through New England with lots of them in the Chesapeake Bay area. There are other slightly different ones in Japan and some along the Indian shores. So I think that makes them fairly unique.

As one might guess that tail is used to steer in the water, but apparently they're strong enough to help the crab flip itself over if a wave or something rolls it over on its back. I find all this fascinating.

Also I was delighted to hear that river otters have made it to Cape Cod and a couple were seen in that particular sanctuary last winter, lying on the ice of a pond in which they'd made a hole, went fishing and were having a gourmet feast. I'd love to see them tho' it's unlikely I will.

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