Individual-based movement models reveals sex-biased effects of landscape fragmentation on animal movement
Authored by Thorsten Wiegand, J D Anadon, A Gimenez
Date Published: 2012
DOI: 10.1890/es11-00237.1
Sponsors:
Global Nation Foundation
Platforms:
Delphi
Pascal
Model Documentation:
Other Narrative
Mathematical description
Model Code URLs:
Model code not found
Abstract
Animal movement and behavior may respond to habitat modification or
fragmentation in non trivial ways, thereby strongly conditioning the
fate of populations. This study aims to understand movement patterns of
non-dispersal animals in both natural and altered landscapes, using the
endangered terrestrial tortoise Testudo graeca as example. We used
individual-based simulation models representing competing hypotheses on
tortoise movement. Model parameterization and selection was based on
radiotracking data and an inverse approach that is able to deal with
observation uncertainty, individual variability, and process
stochasticity. We find that land use intensification had a strong impact
on the movement and behavior of non-dispersing individuals of T. graeca.
In natural landscapes, males and females showed a similar movement and
behavior profile with a strong home behavior component, and little
individual variability. However, in altered landscapes, movement and
behavior greatly varied among individuals, particularly in females, and
males and females showed different movement patterns. Females showed a
wide range of movement patterns, from strong home behavior to an
unbounded movement. Our study shows that population or movement models
that assume single behavioral states for animals inhabiting different
landscape structures can be strongly misleading and, furthermore, that
the impact of landscape modification on movement and behavioral patterns
can be strongly sex-biased. Flexible, individual-based movement models
coupled with inverse parameterization and model selection approaches
proved useful in understanding the mechanisms controlling animal
movement patterns.
Tags
Population-dynamics
Heterogeneous landscapes
Simulation-models
Matrix heterogeneity
Home-range models
Statistical-inference
Ecological landscapes
Tortoise testudo-graeca
South-east spain
Desert
tortoises