Reproductive strategy in hermit crabs of vellar Estuary

Abstract

<i>Clibanarius longitarsus</i> was found to breed over an extended period of the year from March through October with 2 distinct peaks. Breeding in <i>C. padavensis</i> was between March and September with a single peak. Even though <i>C. olivaceus</i> and Diogenes avarus were found to breed throughout the year, reproductive activity during monsoon months was restricted. Two breeding periods were observed in <i>Coenobita cavipes</i> with quiescent periods in between. Reduced salinity with sparse distribution of planktonic food for the larvae during monsoon seemed to restrict breeding in estuarine hermit crabs, and higher saline conditions with plenty of planktonic food for the larvae appeared to be favourable for breeding activity in them. But <i>C. cavipes</i> was found to breed in the months of reduced salinity. Different peak periods of breeding among these, whose larval stages are released into the same environment, appeared to be timed so as to maximize the survival rate of larvae and to prevent high mortality of larvae due to competition between them for food and shells.