Use of Integrated Modeling to Enhance Estimates of Population Dynamics Obtained from Limited Data
Résumé
Demographic data of rare and endangered species are often too sparse to estimate vital rates with sufficient precision for understanding population growth and decline. Yet, the combination of different sources of demographic data into one statistical model holds promise. We applied Bayesian integrated population modeling to demographic data from a colony of the endangered greater horseshoe bats (Rhinolophus ferrumequinum). Available data were the number of subadults and adults emerging from the colony roost at dusk, the number newborns from 1991 to 2005, as well as recapture data of subadults and adults from 2004 and 2005. Survival rates did not differ between sexes and demographic rates remained constant across time. The greater horseshoe bat is a long-lived species with high survival rates (first year: 0.49 [SD: 0.06], adults: 0.91 [SD: 0.02]) and low fecundity (0.74 [SD: 0.12]). The yearly average population growth was 4.4%. Had we analyzed each data set separately, we would not have been able to estimate fecundity, the estimates of survival would have been less precise and the estimate of population growth biased. Our results demonstrate that integrated models are suitable for obtaining crucial demographic information from limited data.
Origine : Fichiers produits par l'(les) auteur(s)