Dka. Barnes, ECOLOGY OF TROPICAL HERMIT-CRABS AT QUIRIMBA ISLAND, MOZAMBIQUE - A NOVEL AND LOCALLY IMPORTANT FOOD SOURCE, Marine ecology. Progress series, 161, 1997, pp. 299-302
The semi-terrestrial hermit crabs Coenobita cavipes and Coenobita rugo
sus are both highly abundant in the supra-littoral zone of Quirimba Is
land, northern Mozambique. In the open sand scrub environment the prin
cipal food sources were mangrove propagules and algae for C. cavipes a
nd rotting terrestrial vegetation for C. rugosus. Increased use of the
mangrove habitats on Quirimba Island by the local human population ha
s resulted in human faeces as a potential source of food for hermit cr
abs. The level of use of this resource differs between the 2 species a
nd between habitats, but not significantly between day and night. Both
species exhibited gregarious behaviour on food items, particularly C.
cavipes on human faeces (up to 61 individuals on 1 food item). Both s
pecies exhibited cannibalism during the study period, but this constit
uted less than 1% of their diet. The foraging distances of both specie
s increased with individual size and differed with habitat in C. cavip
es.