Holarctic Marmots as a factor of Biodiversity.
Rumiantsev V.Yu;, Nikol'skii A.A. & Brandler O.V. eds.,
3d Conference on Marmots (Cheboksary, Russia, 25-30 August 1997),
Moscow ABF 1997, 216p., 98-99 (Russian), 143-144 (English).
SURVIVAL OF THE ALPINE MARMOT (MARMOTA MARMOTA L.): A CAPTURE-RECAPTURE STUDY OF THE
POPULATION FROM LA SASSIERE (VANOISE, FRANCE)
E. Farand, D. Allaine, J. Coulon
Laboratoire de Biologie des Populations d'Altitude, Université Claude Bernard Lyon
1, Villeurbanne Cedex, France
Population dynamics depends on three main demographic parameters according to age class: survival by sex, females breeding success, and proportion of breeding females. Obviously, the quality of dynamics analysis is directly related to the quality of the estimations of demographic parameters. Since ten years, powerfull and flexible statistics tools have been developped to estimate survival using marked animals: the capture-recapture models (Lebreton et al., 1992).
More than survival estimators, the capture-recapture models allow us to model survival variations and to test biological hypotheses, in order to know which factors are involved in survival variations: are they specific (sex and age of individuals), or environmental ? Thus we can understand the part of ecological and evolutionnary processes in population dynamics.
In this paper, we present the first results of a study about Alpine marmot (Marmota marmota L.). We estimated and modelled the survival of Alpine marmots in the population of la Sassiere (French Alps), using a seven years dataset (1990 to 1997). Our aim was to answer to three questions :
1) The Alpine marmot presents no sexual dimorphism : is the survival the same for the two sex, in agreement with evolutionary predictions ?
2) The marmots are dispersing from two years of age. Is there a difference between young and adult survival ?
3) Environment is very sharp in the valley of la Sassiere (elevation: 2400 m). Has it an influence on marmot survival, and which environmental factors are involved