Constrasting Effects of Habitat Fragmentation on the Scorpion Cercophonius Squama and an Amphipod

Populations of the scorpion Cerocphonius squama and the terrestrial amphipod, Family Tallitridae, were monitored by pitfall trapping in southeastern Australia for 8 yr as part of a field experiment to study the effects of habitat fragmentation and remnant habitat patch size on biological diversity, for 3 yr prior to the fragmentation treatment, and 5 yr thereafter. The abundance of scorpions did not change significantly with habitat fragmentation and there was no discernible effect of remnant size. The abundance of amphipods in the remnants relative to that in the controls decreased markedly after fragmentation, more so on smaller remnants than on larger ones. By reason of their ecological and biological characteristics, scorpions seem resistant to the changed ecological conditions brought about by habitat fragmentation, at least in the short term, whereas amphipods are more susceptible. It is not yet possible to generalize about the responses of species to habitat fragmentation. Management of fragmented ecosystems to maintain biological diversity should be directed at populations of species because different species respond differently.