from the specimen drawer

from the specimen drawer

Wednesday, October 14, 2009

Blue Crabs- Mean but Cute!

Here is a photo I took of a blue crab, Callinectes sapidus, giving birth:
photo copyright 2008 

I'm just kidding!!! It's really a blue crab cloning itself through asexual budding. Just kidding again! Did I make anybody go "What the &*#$@%!!!". Blue crabs are strictly into copulation (sexual reproduction only). And they do not pop out ginormous babies (female carries millions of fertilized eggs under her apron which she will eventually release into the ocean). This is actually a photo of a blue crab shedding (molting) its carapace. These are photos I took while doing research with a guy who runs a blue crab shedding facility. Here's another one. This is the only time I've thought of a blue crab as being cute- look at her squooshy, little, bent lateral spines. Aaaaaaaaah....

photo copyright 2008

Though I have seen it over and over there is something fascinating and miraculous about this event that takes place about thirty times in an adult crab’s short life. The blue crab will shed, or molt, its shell when its inner body becomes too big to be contained in its rigid exoskeleton. They actually increase their body size by about 25%. In this next photo you can really see the dififference in carapace size.

photo copyright 2008 

The crab appears to be busting open, thus the common nickname of “buster crab” that is given to this animal during this stage of ecdysis. With much effort and with the aid of hydrostatic pressure from water the crab has taken in during the process of molting the blue crab then works its way backwards out of its shell. Not only does the blue crab have to wiggle all of its new legs out of their old encasings (even the skinny claw tips), its many fine gill layers and the coverings of its eye stalks must also cleanly detach from a thin exoskeleton.

The crab comes out completely soft. Here is a good closeup of one of her bent lateral spines.
photo copyright 2008 

Here are some soft shelled crabs taking a little nap together in a box. I lied again. They are waiting to be cryogenically frozen. Well not exactly. But they will be put in the refrigerator (essentially slows down crab's metabolism to stop the hardening process of the shell) on a little bed of damp newspaper and covered with a little damp newspaper blanket to keep their gills moist so they are alive when they reach the restaurant where they will be breaded and dropped, screaming, into a vat of hot oil. Just kidding again. They only moan quietly to themselves.

Photo copyright 2008

Ultimately, the soft shell crab will end up on someone's plate with legs hanging out the sides of two slices of white bread which your child will stare at in horror thinking you are about to eat a giant, fried bug sandwich, thereby ruining any future chance your child will have of enjoying (even trying) soft shell crabs, which I hear are really delicious.

Here's to you blue crab. You're mean and nasty but we love you anyway.

1 comment:

  1. Sorry if I missed it -- wondering how long a crab would live if we didn't eat 'em.