Decline and recovery of a large carnivore: environmental change and long-term trends in an endangered brown bear population
Authored by Thorsten Wiegand, Cano Isabel Martinez, Taboada Fernando Gonzalez, Javier Naves, Alberto Fernandez-Gil
Date Published: 2016
DOI: 10.1098/rspb.2016.1832
Sponsors:
European Union
Spanish Ministries
Platforms:
No platforms listed
Model Documentation:
ODD
Model Code URLs:
Model code not found
Abstract
Understanding what factors drive fluctuations in the abundance of
endangered species is a difficult ecological problem but a major
requirement to attain effective management and conservation success. The
ecological traits of large mammals make this task even more complicated, calling for integrative approaches. We develop a framework combining
individual-based modelling and statistical inference to assess
alternative hypotheses on brown bear dynamics in the Cantabrian range
(Iberian Peninsula). Models including the effect of environmental
factors on mortality rates were able to reproduce three decades of
variation in the number of females with cubs of the year (Fcoy), including the decline that put the population close to extinction in the
mid-nineties, and the following increase in brown bear numbers. This
external effect prevailed over density-dependent mechanisms (sexually
selected infanticide and female reproductive suppression), with a major
impact of climate driven changes in resource availability and a
secondary role of changes in human pressure. Predicted changes in
population structure revealed a nonlinear relationship between total
abundance and the number of Fcoy, highlighting the risk of simple
projections based on indirect abundance indices. This study demonstrates
the advantages of integrative, mechanistic approaches and provides a
widely applicable framework to improve our understanding of wildlife
dynamics.
Tags
Dynamics
Mortality
patterns
Extinction
Yellowstone grizzly bears
Ursus-arctos
Cantabrian mountains
Northern
spain
Food-habits
Reproductive strategy