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FEATURE ARTICLE

Classified Information
Kingdom – Animalia
Phylum – Arthropoda
Class – Malacostraca
Order – Decapoda
Family – Portunidae
Genus – Callinectes,
species – sapidus
Scientific Name (Original authority – Rathbun, 1896)
Callinectes is Greek for "beautiful swimmer" and sapidus is Latin for "tasty" or "savory".
Feeding
C. sapidus may provide a link between the benthic and pelagic food webs since they occupy overlapping niches throughout their life stages. They are omnivorous opportunistic predators that have a diet including a variety of bivalves, crustaceans, annelids, fish and plants. They are preyed upon by larger fish – striped bass, drum, spot, and croaker.
Range
C. sapidus range from Nova Scotia to northern Argentina – although they are uncommon north of Cape Cod, MA, but found in abundance in Chesapeake Bay and the Atlantic and Gulf coasts of Florida (although, Maryland legislators passed a bill to place restrictions on recreational crab harvests for 2001 that limit crabbers to 2 dozen/day without a license and 1 bushel/day with a license). They have been successfully introduced into European waters and are abundant in the Nile River Delta of Egypt and in Israel. Additionally, they have been found in San Francisco Bay and are considered to be a potential threat to the natural crab population.
Growth
Because of the chitinous exoskeleton growth is accomplished by molting or shedding with the new shell forming under the old shell. Carbohydrate, proteins and calcium of the old shell are dissolved and stored in the body for use in the new shell. Muscle attachments are loosened and the stomach lining is lost during a molt and reattached and reformed to the new shell. The new shell is soft and elastic and a large amount of water needs to be absorbed. About 72 hours later the new shell hardens and the crab can by 25–35% larger than its original size.
Reproduction
C. sapidus are sexually mature in 12 to 16 months and females only mate once in their lifetime (called their terminal mote) while males can mate several times. Females have the ability to store sperm for multiple spawnings. Newly hatched larval crabs – zoea – require high salinity. Consequently, all spawning occurs at the mouth of bay in VA. Zoea are advected offshore where they continue to develop and transform into megalopae upon which time they reenter the Bay. Bay grass beds and oyster reefs provide habitat for the crabs to metamorphose into a juvenile. Crabs may be conceived in MD, but have VA birth certificates!
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