Preferences of Peromyscus lecucopus for pupae or larvae of Lymantria dispar and for seed in northern Michigan.

Abstract

Oak masting affects population density of the white-footed mouse in the eastern U.S. Mouse predation affects gypsy moth population size and may help control gypsy moth outbreaks. In these experiments, we examined whether similar interactions between oak masting, mice, and gypsy moth populations occur in northern Michigan. We used a field experiment to demonstrate that mice consume gypsy moth pupae in the wild, although only two out of 80 pupae provided were eaten. In controlled laboratory experiments conducted in cages, mice chose seed over larvae in 9 of 18 trials (Binomial test, p>0.05). In 18 of 25 trials, a large larvae was eaten prior to a small larvae (Binomial Test, p<0.05). When seeds were made available, large larvae were preferred in 8 of 9 trials, indicating no observed effect of seed availability on preference for large larvae over small (X2=2.0, p>0.05, df=1).