Nest attendance in male meadow voles: the role of the female in regulating male interactions with pups

Abstract

Abstract. Nest attendance by male and female meadow voles, Microtus pennsylvanicus , was monitored in 24-h recordings. Fathers housed with mothers and their pups, but with no other adults present, were in the natal nest for much of the observation period. When unfamiliar males were present, instead of, or in addition to, the fathers, females prevented the unfamiliar males from entering the natal nest, and showed reduced tolerance to the fathers' attempts at nest entry. Females housed with unfamiliar males were the only voles to spend more time in the nest at night than during the day, which may be related to the only instance of infanticide occurring when an unfamiliar male successfully entered the nest at night. The introduction of an oestrous female did not reduce the amount of time the father spent in the nest, although several fathers mated with the oestrous females. In another experiment, females were found to be temporarily less tolerant of fathers that were removed during pregnancy and returned after the pups were born, but after renewed contact, the females allowed the males to enter the nest. Fathers tested in the absence of mothers spent a substantial portion of the test time with pups, and effectively prevented unfamiliar males from gaining access to their pups. These results were related to the seasonal changes in nest sharing in meadow voles, suggesting that male reproductive tactics should be flexible to accommodate changes in mating opportunities and changes in the value of biparental care.