Horseshoe Crabs 2012/2013: population estimation

Introducing: Horseshoe Crabs in the Classroom, Take 2

During the 2011/2012 school year, we had a program called Horseshoe Crabs in the Classroom at our elementary school. This program is offered through the Maryland Department of Natural Resources and it's a great idea for a number of reasons - letting kids learn about these incredible pre-dinosaur animals while, maybe, helping add a few more of these amazing animals to the Chesapeake Bay.

Last year, we ended up with no live horseshoe crabs (HSC) and I think this was because of over-zealousness on my part for ridding the aquarium of an unwanted fungus or at least what I thought was fungus. The 4th graders, though, were very enthusiastic and they learned a lot about the critters even though they never saw a live one in their classroom. Sigh.

This year, though, now that the teacher (me) is a bit more experienced, I think we'll have better luck. So here's Take 2...

Sunday, July 15, 2012

July 15 - 1st molts after hatching

How colorful is this photo? It's all thanks to the molts being in a glass bowl on a red table. But aside from the color, the interesting part is that these are the first molts after the larvae hatched from the eggs. There's no tail - the upper center one shows that best, perhaps.

This one shows the underside of a molt. This doesn't look exactly like a horseshoe crab yet - no tail! - but it's one of the early stages.

And finally for today - a picture of the corner of the aquarium where most of the babies hang out. The blue glob is actually the aerator stone - it looks fuzzy because of the air bubbles coming out of it. This is not a high quality photo but I'm guessing this shows about 50 and another 20 are in the rest of the aquarium. They get active when I add the baby brine shrimp - hungry little fellows!