Q. We like to catch blue crabs off the dock when we visit the beach, but when the weather cools we can't find any. Where do they go?

A. During winter, blue crabs (Callinectes sapidus) pass the days in deeper water, burrowed in muddy or sandy bottoms. There they lie dormant with only their antennae, the tips of their eyestalks and small breathing channels visible above the mud. About March, the crabs dig out and begin their spring and summer feeding, shedding and breeding.

Male blue crabs are called "jimmies." Females are called "sooks." Females -- the ones with red-tipped claws, produce multiple clutches of orange eggs, sometimes five or six in a single season. Large females produce more eggs than small females. Egg-carrying females are called "sponge crabs." She-crab soup, a favorite seafood delicacy, is made from crab eggs.

Hard crabs, peelers and soft crabs are harvested commercially March through May. Harvesting continues through summer and fall, according to regulations set by the N.C. Division of Marine Fisheries, which governs size and number of catch.

In North Carolina, blue crabs are the state's most valuable fishery. According to the National Marine Fisheries Service, North Carolina was the top blue crab-producing state in the country from 1994 to 1999. However, according to the N.C. Division of Marine Fisheries, the harvest declined by more than $12 million in 2004. This resulted in new recreational and commercial size limits being put in place and the release of large females to try and increase the spawning population.

The state operates three public aquariums; one in Pine Knoll Shores, another at Fort Fisher and a third on Roanoke Island. The aquariums are administered by the North Carolina Department of Environment and Natural Resources, and are designed to inspire appreciation and conservation of North Carolina's aquatic environment.

For more information about the Aquariums, visit www.ncaquariums.com, or call 800-832-FISH.

Sherry White works for the N.C. Aquariums.