Intraspecific Spatial Relationships of Two Species of Terrestrial Salamanders

Nishikawa, Kiisa

ABSTRACT: Intraspecific spatial relationships of two species of terrestrial salamanders, Plethodon teyahalee and P. jordani were studied in the southern Appalachian Mountains. The movements of 24 P. teyahalee and 40 P. jordani individuals, uniquely marked with fluorescent dust, were monitored from May-Sept. 1983. Distances moved between recaptures were recorded, and the minimum convex polygon method was used to estimate home range areas. Both species occupied fixed home ranges, and all age classes of both species shared on average less than 10% of home range area with a conspecific of the same age or sex. Home ranges of P. teyahalee, the larger species, were smaller, more exclusive, and more likely to contain a retreat hole than home ranges of P. jordani. All 3 yr old or older P. teyahalee had at least one retreat hole in their home range, which they used nearly every night. It appears that retreat holes may be defended by P. teyahalee, but there was no evidence that retreat holes were in limited supply. Home ranges of P. jordani were not associated with cover objects or with retreat holes, which suggests that neither of these resources are defended. The only resource that appears to be used by both species is space (i.e., the forest floor itself, which contains the multi-purpose home range area that both species use for foraging and courtship). This study supports two predictions of the hypothesis that these salamanders are intraspecifically territorial: 1) individuals occupy fixed home ranges; and 2) these areas are exclusive with respect to rivals