Eight‐legged swimmers: Behavioral responses to floods in two South American spiders

Abstract

AbstractArthropods inhabiting floodplains have to cope with regular cycles of wet and dry conditions. Allocosa senex and Allocosa marindia are two sympatric and synchronic sand‐dwelling wolf spiders that construct burrows along South American coasts and are subject to periodic floods. Our objective was to study tolerance to immersion and describe the behavioral responses to that event in A. senex and A. marindia. We placed each spider in a terrarium with sand as substrate to allow burrow construction. Then, we gradually increased water levels and recorded the behavioral responses for 30 min. None of the individuals died during the artificial flood. More adults of A. senex performed “dives” and “floats” compared to A. marindia. Also, A. senex showed higher occurrences of “floats,” “swims,” and swam for longer than A. marindia. Finally, females of both species swam more frequently than males. Our findings indicate that both Allocosa are able to withstand floods, showing differential tactics according to the life histories of each sex and species.