Evol Ecol Res 6: 433-442 (2004)     Full PDF if your library subscribes.

Effect of birth and weaning mass on growth,

survival and reproduction in the bank vole

Hannu Ylönen,* Taina J. Horne and Marjaana Luukkonen

Department of Biological and Environmental Science and Konnevesi Research Station, University of Jyväskylä, PO Box 35, Jyväskylä 40014, Finland

Author to whom all correspondence should be addressed.
e-mail: hylonen@bytl.jyu.fi


Among mammals, physiological constraints and resource availability limit resources for reproduction. Limited resources can be allocated to either large litters with small offspring or to fewer but heavier pups. High birth weight is thought to be related to better survival and earlier onset of reproduction. We studied the effects of birth and weaning masses on future survival and reproduction of bank voles (Clethrionomys glareolus) in a combined laboratory and field experiment. We reared voles in the laboratory and cross-fostered pups after birth to randomize maternal effects before weaning. Using 256 laboratory-bred individuals, we conducted two separate field experiments over 3–4 weeks in large outdoor enclosures to study the effects of birth and weaning weights on individual survival and reproduction. Males that were heavy at birth were also heavy as adults. Females heavier at birth produced larger litters under favourable conditions of the earlier replicate, but not in the later one. Mass at birth or weaning did not affect survival. There was great variation in growth and reproduction over time presumably related to environmental conditions. The first run seemed to be more favourable, especially for body condition of adults. In the second run, the later season might have had a negative effect on the proportion of females breeding. However, most probably the voles suffered from food depletion due to heavy rains. In conclusion, we did not find any simple positive effect of birth mass on the success of individuals. It would appear that the effect of high birth mass is not an unambiguous issue in life-history evolution.

Keywords: bank vole, birth mass, compensatory growth, life histories, reproduction, survival, weaning mass.

IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.


        © 2004 Hannu Ylönen. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.