Predation and Competition in Ambystoma Larvae: Field and Laboratory Experiments

Abstract

The rate of predation of A. opacum larvae on A. maculatum larvae was shown to vary with the size and density of the predator in the laboratory. An increased density of both the predator and therapy in field enclosures increased the daily mortality rate of the prey A. maculatum, but did not significantly decrease the number of survivors. Intraspecific competition in both species was shown to be density-dependent in the laboratory. The growth of A. opacum was inhibited by an increased density of conspecifics in field enclosures. Interspecific competition was demonstrated in the laboratory and in field enclosures. The data suggest that the 2 spp. are probably more affected in nature by the predator-prey relationship than by interspecific competition.