Biased adult sex ratio can affect fecundity in primiparous moose Alces alces

摘要: Recruitment rate has declined in many Norwegian moose Alces alces populations during the last two decades and at same time population size increased proportion of males to females decreased. Although density-dependent food limitation may explain part decrease productivity, we evaluated what extent decline could also be a result an insufficient number fertilise all females. To test this hypothesis, compared, based on ovary analyses, age-specific variation fecundity rates eight with annual adult sex ratio. Differences female age body mass explained significant variance probability pregnancy. In addition, there was relationship between ratio pregnancy among 2-year-old females, but not older Because biased only affects first-time breeders, effect recruitment limited. However, call attention other possible effects ratio, e.g. delayed parturition date, which long term productivity through survival fecundity.