Litter sizes of Microtus montanus in the laboratory
Pinter AJ. 1965. Litter sizes of Microtus montanus in the laboratory. Journal of Mammalogy. 46(3):434-437
Consecutive litter sizes of Microtus montanus are reported on the basis of 314 litters produced by 43 females in the laboratory. Irrespective of the age (subadult or adult) of females at mating, mean litter sizes increase from the first through the fifth litter. Then a decreasing trend ensues. Mean litter size of first litters in females that start breeding as subadults is 3.6, for those that start as adults-4.2. Mean litter size of fifth litters for subadults is 4.9, for adults 5.8. These differences between mean litter sizes of subadults and adults are statistically significant, indicating that in Microtus montanus litter size is affected by the age of the female at the onset of her reproductive activity. This observation on litter sizes is further supported by embryo counts collected from subadult and adult females in natural populations. The laboratory and field data are discussed in terms of their implications at the population level.
- Type
- Journal Article
- Authors
- Pinter, Aelita
- Units
- GRTE
- Keywords
- Animal Studies, Animals, Jackson Hole, Mammals, Reproduction, Rodents (Rodentia), Voles (Cricetidae), WY
- Subjects
- Ecological Framework: Biological Integrity | Focal Species or Communities | Mammals