Aspects of the ecology and life history of the little known theraphosid Nesiergus insulanus are determined
on Frégate Island in the Seychelles archipelago. The general behaviour of this species is revealed to be
comparable to that of other theraphosids, with field and captive observations establishing that they are a
generalist and opportunistic species. The defensive behaviour of the species is determined to be based
primarily on the avoidance of conflict situations, with overt aggressive behaviour seldom displayed. Although
the opportunistic existence that this species has developed is probably obligatory due to their sedentary
lifestyle and limited availability of resources, this behaviour nonetheless allows the species to occupy diverse
habitats and exploit niches unavailable to more specialized species.