Behavioural ecology of crabs in temperate mangrove swamps

Patterns of distribution of crabs inhabiting burrows in three temperate mangrove swamps near Sydney, New South Wales, were described. Heloeoius cordiformis (an ocypodid) did not exhibit a consistent pattern of distribution among three tidal zones, but was always associated with well— drained mounds of substratum within zones. Paragrapsus laevis (a grapsid) tended to be most abundant in the lower two zones on the shore and usually inhabited burrows in the moist or submerged flats between mounds. Sesarma erythrodactyla (a grapsid) was distributed fairly evenly among the three tidal zones and also between mounds and flats. H. cordiformis hibernated in burrows from June through August or September. Overall abundances also varied seasonally, but trends were inconsistent among the three swamps sampled