Survival in fluctuating bank vole populations: seasonal and yearly variations

• Published in: Oikos Vol. 98; no. 3; pp. 467 - 479
• Main Authors: Crespin, L. (Oslo Univ. (Norway)), Verhagen, R, Stenseth, N.C, Yoccoz, N.G, Prevot-Julliard, A.-C, Lebreton, J.-D
• Format: Journal Article
• Language: English
• Published: Copenhagen Munksgaard International Publishers 01.09.2002; Blackwell Publishers; Blackwell
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Animals; BELGICA; BELGIQUE; BELGIUM; Biological and medical sciences; CAMPAGNOL; Coniferous forests; Crop production; Deciduous forests; Demecology; DEMOGRAFIA; DEMOGRAPHIE; DEMOGRAPHY; Food availability; Food supply; FRUITS; FRUTAS; Fundamental and applied biological sciences. Psychology; GRAINE; Mammalia; Modeling; PERIODICIDAD; PERIODICITE; PERIODICITY; Population dynamics; QUERCUS; Rodents; SEASONAL VARIATION; Seed crops; SEEDS; SEMILLA; SUPERVIVENCIA; SURVIE; SURVIVAL; TOPILLOS; VARIACION ESTACIONAL; VARIATION SAISONNIERE; Vertebrata; VOLES; Belgium; Europe; Availability; Trophic factor; Rodentia; Environmental factor; Long term variation; Survival; Cycle; Vertebrata; Clethrionomys glareolus; Mammalia; Capture recapture method; Seasonal variation; Muridae; Population dynamics; Dynamic model; Food supply; Ecological abundance
• ISSN: 0030-1299; 1600-0706
• DOI: 10.1034/j.1600-0706.2002.980311.x

For most organisms, both within-year (i.e. seasonal) and between-year variations in demography are important components in shaping the population dynamic patterns observed on a multiannual scale. These two sources of variation have, however, rarely been studied simultaneously. Most of the recent work on small rodent population dynamics, for example, has focused on between-year variation. Densities of seed- and fruit-eating rodents, such as the bank vole (Clethrionomys glareolus), are in particular known to have between-year variation related to seed crop production. Here we report on the analysis of a long-term (1976-1982) capture-mark-recapture (CMR) study of the bank vole in Belgium. The study was done on two grids, an open and a fenced grid. As part of the CMR statistical analysis, we propose a general modelling approach which allows for a detailed understanding of the relative importance of seasonal and between-year variation in survival. We demonstrate that most of the seasonal variation corresponds to a lower apparent survival in spring compared to the rest of the year. During winter, apparent survival was lower on the open grid than on the fenced grid. Dispersal is therefore concluded to be an important determinant of the seasonal pattern. The between-year variation in survival is largely attributable to variation in seed crops, and is comparable in magnitude to the seasonal variation.