Phenologic influences on cohort-specific reproductive strategies in mice (Peromyscus polionotus)

Journal Article · Sat Dec 01 04:00:00 EST 1979 · Ecology; (United States)

DOI:https://doi.org/10.2307/1936960· OSTI ID:7065489

Dapson, R W

Breeding seasons and birth cohorts were defined for two populations of mice (Peromyscus polionotus). Cohort-specific differences in reproductive effort were correlated with residual reproductive value. In one population, mice lived nearly 2 y, reproduced at moderate rates, and showed few differences in cohort-specific reproductive strategy. Mice from the other population lived < 1 y, and spring-, summer-, and fall-born females exhibited markedly different reproductive strategies. Cohorts able to breed in a future season had moderate reproductive efforts, which did not increase risk of mortality. Extraordinary efforts (being pregnant and lactating simultaneously), which seriously increased mortality rate, were undertaken when residual reproductive value became zero. Nestling mortality increased with litter size when there were more than three young per litter, but larger litters still resulted in more weaned young than did smaller litters. These observations provide additional confirmation of the model of Pianka and Parker (1975). It is possible that populations of very short-lived mammals characteristically have seasonal cohorts operating under different reproductive strategies.

• Research Organization: Univ of Michigan, Flint
• OSTI ID: 7065489
• Journal Information: Ecology; (United States), Journal Name: Ecology; (United States) Vol. 60:6; ISSN ECOLA
• Country of Publication: United States
• Language: English

Related Subjects

550100* -- Behavioral Biology
550800 -- Morphology
59 BASIC BIOLOGICAL SCIENCES
ANIMAL BREEDING
ANIMALS
MAMMALS
MICE
MORTALITY
PHENOLOGY
POPULATIONS
REPRODUCTION
RODENTS
SEASONAL VARIATIONS
VARIATIONS
VERTEBRATES