Chimneys are mud mounds built by fiddler crabs that encircle the entrance to their burrow. Their function in many species is unknown. In Uca capricornis, crabs of both sexes and all sizes build chimneys, but females do so disproportionately more often. There are no differences in the immediate physical or social environments between crabs with and without a chimney. Chimney owners spend less ti...

Ghost crabs (Ocypode quadrata) have been implicated in mortality of eggs and chicks of the beach-nesting Piping Plover (Charadrius melodus) whose Atlantic Coast populations are listed as threatened. Through observation and experimentation, we investigated the interactions between ghost crabs and plovers on Wild Beach, a Piping Plover nesting area on Assateague Island, Virginia. This site has a ...

This work was part of the course EC520. The objective of this project is to develop an algorithm for the detection and enumeration of crabs on beach. The basic method is background modeling and background subtraction. Based on several previous frames, the background of current frame can be estimated using median model or non-parametric model. Morphological operation is applied to foreground ima...

The present study investigated the infection status of Paragonimus westermani metacercariae in freshwater crabs (n = 363) and crayfish (n = 31) from October 2007 to October 2008 using the crush method. All of the freshwater crabs, Eriocheir japonicus, were negative for P. westermani metacercariae while 10 (32.3%) of the 31 examined crayfish were positive. The 10 positive crayfish were caught in...

The blue crab, Callinectes sapidus, is a valuable resource in the Coastal Bays, supporting a steady commercial and recreational fishery. Surveys suggest that blue crab abundance fluctuates without an apparent trend, yet there is still a successful annual commercial fishery that even attracts crabbers from the Chesapeake Bay. Since 1990, commercial landings for crabs have averaged from 0.5 to 1....

The terrestrial robber crab Birgus latro L. regulates the composition of its final excretory product (termed P) depending on the availability of dietary salt by reabsorbing ions from urine passed over the gills. Laboratory and field-based studies investigated the nature of the mechanisms of control of this branchial ion uptake. B. latro were prepared such that their branchial chambers could be ...

ABSTRACT Ocean acidification can affect the ability of calcifying organisms to build and maintain mineralized tissue. In decapod crustaceans, exoskeleton is a multilayered structure composed chitin, protein mineral, predominately magnesian calcite or amorphous calcium carbonate (ACC). We investigated effects on mature (post-terminal-molt) female southern Tanner crabs, Chionoecetes bairdi. Crabs...