The effects of weather on runway use by rodents

Abstract
The effects of weather on runway use by four species of rodents were investigated using animal activity data obtained from a sand track. Species studied were meadow vole (Microtus pennsylvanicus), deer mouse (Peromyscus maniculatus), meadow jumping mouse (Zapus hudsonius), and woodland jumping mouse (Napaeozapus insignis). Runway use was quantified using the quotient of the activity inside to the activity outside the runway. The weather data were analyzed using a principal component analysis. The degree of concordance between the weather factors and runway use index was assessed by canonical correlation. Results showed that runway use decreases during warm, rainy, moonless nights. During these weather conditions, a predator's ability to find small rodents may be impaired, and the rodents could explore outside their runways to find new food patches.