Burrowing ability and behavior of salamanders of the genus Ambystoma

Abstract

The burrowing ability and behavior of five species of fossorial salamanders of the genus Ambystoma were examined in the laboratory. Individual salamanders were subjected to three experimental treatments to test the hypothesis that salamanders do not actively dig their own burrows but alternatively enlarge cracks, crevices, and invertebrate or small mammal burrows for occupancy. One species, A. tigrinum, actively dug burrows under all experimental treatments while A. talpoideum actively dug 50% of the time. The other species (A. opacum, A. annulatum, A. maculatum) burrowed passively by using their snout and body to enlarge holes or cracks provided. Individual salamanders not able to burrow (actively or passively) underground incurred significant water loss (25–39%) and several died after a 24-h test period. Digging ability was not clearly related to snout–vent length, head width, or forelimb diameter. These data suggest that the digging ability of ambystomatid salamanders may be a behavioral adaptation and is not simply related to morphology.