Intraspecific Spacing and Interaction within a Population of Desmognathus quadramaculatus

We studied spacing and interactive behavior in a population of Desmognathus quadramaculatus in Georgia. During 1991, 132 metamorphosed salamanders (35-109 mm SVL) were marked and released; 207 recaptures were made of 87 individuals. Mean home-range area was 1207 cm2, and mean salamander density was 1.4/ m2. Smaller salamanders (< 70 mm SVL) predominated in the stream, and larger ones occurred more frequently in the stream bed between the water line and the forest. Smaller individuals spent more time wandering whereas adults remained in refugia. Preferred refugia were rock crevices; larger salamanders also commonly used burrows at the bank/water interface and in the dirt banks of the stream bed. Spacing of home-range centers did not differ from random; spacing of individual salamander locations was contagious. In interactive experiments performed in the field in 1994, adults ate juveniles, and juveniles fled from adults. Individuals in refugia reacted aggressively toward intruders regardless of body size differential. Wandering salamanders of similar size were aggressive approximately 50% of the time. Desmognathus quadramaculatus defends a territory of repeatedly used refugia, from which it excludes conspecifics through a probable combination of pheromonal advertisement and aggressive interference, with cannibalism being the ultimate aggressive response. Individuals outside refugia exhibit a series of aggressive and escape behaviors with small salamanders avoiding large ones, as well as their microhabitat. The spacing patterns observed do not fully fit predictions based on current models of spatial interactions of Desmognathus.