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Scott DIET Mississippi’s Gateway to the Gulf The striped hermit is an opportunistic feed- Come discover the er and uses its claws to capture and break open through hands-on programs for fam- MARINE EDUCATION LEAFLET #36 small bivalve molluscs. Striped hermits are also and will feed on dead plants and ilies and groups of all ages at the... .

REPRODUCTION Striped hermits reproduce during the warmer months. Their northward distribution appears to be limited on the Atlantic coast by the cooler waters north of Virginia. The The Striped requires temperatures of 77 F (25 C) for the two-month period of larval development. J. L. Scott Marine Education Center & Aquarium Hermit 115 Beach Blvd. (Hwy 90) Biloxi, MS 39530 MIGRATION (228) 374-5550 [email protected] Striped hermits leave the shore and move to www.usm.edu/aquarium deeper waters during the colder months. They come together and remain offshore through the winter. In the spring they return to the shallows where they mate.

--By Harriet Perry Produced by Center for Fisheries Research and Development for GULF COAST J.L. Scott Marine Education Center & Aquarium RESEARCH LABORATORY

AA/EOE/ADAI © 2004 Gulf Coast Research Laboratory THE STRIPED ( vittatus) CLASSIFICATION carapace, the shield-like plate that covers the Like shrimp and lobsters, hermit are deca- front part of the body. DISTRIBUTION pod : They have 10 legs. The first legs are The striped hermit crab, Clibanarius vittatus, modified into claws or chelipeds. In hermit crabs, the GROWTH is one of the most conspicuous summer inhabi- second and third pair of legs extend outside of their Like other crustaceans, the striped hermit has tants of shallow, saline waters in northern Gulf shell home and are used for walking. Clibanarius gets an composed of a protein called chitin. of Mexico estuaries. These crabs occur widely its common name from the light-colored stripes that The chitin of the carapace and walking legs is along the Atlantic and Gulf coasts of North run along the walking legs. The fourth and fifth legs impregnated with calcium salts which make these America and are found in Central and South are much smaller and are not visible when the crab is structures hard. The chitin of the abdomen is not America as far south as Brazil. in its shell. These small legs are used to grip the calcified and is soft and elastic. Hermit crabs must inside of the shell to hold the soft abdomen in place. shed their old exoskeleton to grow. With growth They also remove sand and waste from the shell. comes the need for a new and larger home. antenna Hermit crabs are further classified as anomurans. Hermits are always on the lookout for a new The anomurans are not "true crabs." True crabs (like shell. When they see a prospective shell, they walking cheliped leg the blue crab) belong to a different decapod group, inspect it with their claws. If the new shell is or claw the Brachyura. Brachyurans have well-developed fifth acceptable, the crab quickly leaves its old shell and legs and lack the anomurans' distinct uropods, tries out the new one. Hermit crabs always use empty appendages at the end of the abdomen. shells and never kill the original snail occupant. In some areas, the shortage of empty shells limits crab ADAPTATIONS growth and may limit population size. The number Some anomuran decapods, like the hermit crabs, of eggs produced by females is related to crab size. have evolved the habit of protecting their soft, vulner- Females who cannot find larger shells grow more carapace able abdomens by borrowing the shells of gastropods slowly and produce fewer eggs. (snails). The soft abdomen of the striped hermit is Striped hermits occupy a variety of shells depend- twisted to fit around the central spire of the snail ing upon the hermits’ life stage and their location in shell. The uropods at the end of the abdomen the estuary. Shells of the oyster drill, Thais, the moon uropod anchor it in place. The uropods have gripping sur- snail, Neverita duplicata, and whelks of the abdomen faces. Along with the fourth and fifth legs, they hold Busycon are commonly occupied by adult hermit the hermit crab firmly in its shell. crabs along the barrier island beaches. Juvenile The striped hermit is highly resistant to drying striped hermits are common in salt marshes and Clibanarius vittatus usually occupy the shells of marsh periwinkles, removed from a snail shell out, an adaptation that allows it to survive in the during the warm months. Hermit Littoraria irrorata, and the olive nerite, Neritina usnea. crab are located above the legs and beneath the