Interference behaviour (aggression and cannibalism) can be influenced by both intrinsic factors, such as animal physiology, size, or motivation, and extrinsic factors, such as presence of competitors, predators, or prey. Our experiment examined the effects of differences in diet quality of focal salamanders and their opponents, and levels of handling on biting by pairs of larval ringed salamanders, Ambystoma annulatum, before and after presentation of prey. Diet quality and handling affect the intrinsic qualities of body size/condition and stress, respectively. Presence of prey and diet quality of opponents are extrinsic factors. Unstressed larvae on high-quality diets bit their high-condition opponents more frequently than those that had been on low-quality diets in both the presence and absence of food. Stressed larvae (all on high quality diets) showed low levels of biting when food was absent. However, when food was present, the level of biting depended on the diet quality of their opponents: stressed larvae bit opponents on low-quality diets more than opponents on high-quality diets. Overall, both intrinsic and extrinsic factors influenced interference behaviour, with larvae on high-quality diets exhibiting relatively high levels of biting unless they had experienced handling stress, and the effect of handling stress depending on the condition of the opponent in paired interactions.
Aggression and territoriality by salamanders and a comparison with the territorial behavior of frogs. In:
Amphibian Biologyvol. 2 p.
HeatwoleH.SullivanB.K. Eds Surrey Beatty & SonsChipping Norton, Australia.
Male-male combats in a polymorphic lizard: residency and size, but not color, affect fighting rules and contest outcome.
The effects of food level and conspecific density on biting and cannibalism in larval long-toed salamanders, Ambystoma macrodactylum.