Cephalopodcast

I have not gone out to the beach as much as I had hoped when I first started What the Shell. But not too far from the horse conch, we found this little fellow.

Stone Crab (Menippe sp.)

The one pictured below is probably a juvenile M. mercenaria, the Florida Stone Crab. That’s based on the range; I haven’t found anything definitive yet.

2 September 2007
New Pass, Sarasota, Florida, U.S.A.
Found crawling on a dead quahog shell.

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Brachyura
Superfamily: Xanthoidea
Family: Menippidae
Stone Crab (Menippe sp.)

Gortoning Myself

I am probably Gortoning myself with this one, but stone crab season begins today in Florida.

Only legal-sized claws (2 ¾ inches) are harvested in the stone crab fishery; crabs are returned to the water alive to generate new claws. Approximately 13 percent of commercially harvested claws are regenerated. The fishing season is open October 15 through May 15 each year, but the harvest of egg-bearing female crabs is prohibited at all times.

Most of the sources on stone crabs note that this is a “sustainable fishery,” owing to the notion that the crabs will regrow their claws. The rate of regrowth varies, taking anywhere from one to three molts before the new claw approaches the same size as the one removed. The molting rate depends on the initial size, sex and environmental conditions of the animal, among other things.

Duress of the Dungeness*

You can file this under duh, but Mark recently noted some new research that indicates crabs with claws removed have increased stress levels which could affect survival rate. As picked up by ScienceDaily:

Professor Bob Elwood, from the School of Biological Sciences studied crabs’ reaction to declawing. Crabs felt increased stress and had a lower survival rate after the removal of one claw.

Professor Elwood said: “We found a strong stress response within ten minutes of taking off one claw and this stress remained after 24 hours. The stress response was greater if the crab was declawed rather than being induced to cast off a claw. So, the stress is not due specifically to claw loss but to the manner of the claw loss.

I don’t imagine most folks will pay much mind to this news. But personally, I’ve cut back tremendously on the amount of meat I consume, mostly for ethical and environmental reasons. And this research doesn’t incline me make an exception for crustaceans, no matter how deliciously sustainable they may be.

Sources

• Blogfish: Removing claws is harmful to crabs
• ScienceDaily: Declawing Crabs May Lead To Their Death, which is a rehash of the original press release from Queen’s University, Belfast.
• NOAA FishWatch fact sheet: Gulf and Florida Stone Crabs (Menippe adina and Menippe mercenaria)
• The 2006 Stock Assessment Update for the Stone Crab, Menippe spp., Fishery in Florida
• A Proposed Evolutionary History of Stone Crabs
• Observations of the Stone Crab Commercial Fishery. From the 2006 season, with a couple of nice vignettes by Florida Wildlife Commission field crew members.
• Creative Loafing, Sarasota: ‘Tis the Season, Sandy claws are coming to town. Brian works in an jab at vegetarians in both the print and podcast versions.

*Forgive me the poetic license, I know they are different species. This also concludes my Blog Action Day report.

Tags: beach, beachcomber, crabs, fisheries, Florida, invertebrates, WYCD

This entry was posted on Monday, October 15th, 2007 at 9:00 pm and is filed under What The Shell?. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.