Many intertidal and shallow water crabs have strong reproductive cycles and migratory larvae. Females release larvae near the time of high water of the larger amplitude nocturnal tides during the semilunar or lunar cycles. Newly hatched larvae move quickly at night toward and into the sea where, weeks later, they develop to megalopae that then ride nocturnal flood tides inshore and up estuaries...

The invasive Asian shore crab, Hemigrapsus sanguineus, has recently been observed occupying salt marshes, a novel environment for this crab species. As it invades this new habitat, it is likely to interact with a number of important salt marsh species. To understand the potential effects of H. sanguineus on this ecosystem, interactions between this invasive crab and important salt marsh ecosyst...

Fiddler crabs (Brachyura, Ocypodidae), like many other marine organisms, disperse via planktonic larvae. A lengthy pelagic larval duration is generally assumed to result in genetic connectivity even among distant populations. However, major river outflows, such as of the Amazon or Orinoco, or strong currents may act as phylogeographic barriers to ongoing gene flow. For example, the Mona Passage...

Intertidal organisms may employ circatidal rhythms to track the tidal cycle, but tidal patterns may vary within a species range and necessitate adaptation to the local tides. Circatidal rhythms were examined in populations of the eastern Pacific fiddler crab Uca princeps (Smith) from four sites with differing tidal characteristics, La Paz (24 10¢N; 110 21¢W), San Blas (21 33¢N; 105 18¢W) and Ma...