Form and Development of Predation on Crickets in Adults of Peromyscus maniculatus bairdi and P. leucopus noveboracensis

Three experiments compared the similarities and differences in attacks on crickets by two species of laboratory-raised cricetid mice, Peromyscus maniculatus bairdi and P. leucopus noveboracensis. In Experiment 1 moderately prey-experienced 1.5-year-old mice of both species concentrated attacks on the crickets' dorsal head. P. leucopus also produced considerable damage to the thorax and showed a greater effect of sessions on the location and latency of attack. In Experiment 2 prey-naive .4to .8-year-old mice of both species initially damaged crickets randomly and were slow to attack, but after two sessions both species attacked rapidly and displayed the same focus on the dorsal head shown in Experiment 1. However, P. leucopus did not display the thoracic focus shown by this species in Experiment 1. In Experiment 3 the P. leucopus from Experiment 2 were retested at 1.5 years of age without further predatory experience and showed the thoracic focus of attack found in Experiment 1. Young adults of both species markedly and similarly increased the speed and focus of predatory attacks on crickets after limited experience. The attack characteristics of older P. maniculatus differed very little from those of experienced young adults, whereas the attack characteristics of P. leucopus changed as a function of both age and subsequent test experience.