It's been a few years since I've seen them at all let alone in big numbers. I think they're awesome creatures. Almost a link to a time well before we were all here. Please try and avoid them while wading. I was just fishing an early season spot and there were mating pairs all over the place. I'm embarrassed to say on a cast I stepped on one and went a $$ over tea kettle in my waders. The crab was fine but I got soaked lol. Not an environmentalist or anything but keep an eye out. They're pretty cool. End of rant

they are of extreme value to humans and science. they are BLUE blooded and donate blood for research because it has so much immune system booting special proteins.

http://www.natureworldnews.com/articles/8814/20140901/horseshoe-crab-blood-harbors-protein-used-in-medical-research.htm