Population persistence in landscapes fragmented by roads: Disentangling isolation, mortality, and the effect of dispersal
Authored by Ana Ceia-Hasse, Laetitia M Navarro, Luis Borda-de-Agua, Henrique M Pereira
Date Published: 2018
DOI: 10.1016/j.ecomodel.2018.01.021
Sponsors:
German Research Foundation (Deutsche Forschungsgemeinschaft, DFG)
Platforms:
C++
Model Documentation:
ODD
Flow charts
Model Code URLs:
https://github.com/anaceiahasse/landsim
Abstract
Linear infrastructures, one of several forms of land-use, are a major
driver of biodiversity loss. Roads impact populations at many levels,
with direct road mortality and barrier effect contributing to decreased
population abundance, higher isolation and subdivision, and therefore to
increased extinction risk. In this paper, we compared the effect of road
mortality and of the barrier effect on population isolation, persistence
and size, and assessed the interaction of these effects with dispersal.
We used a spatially explicit, process-based model of population dynamics
in landscapes fragmented by varying levels of road density. We modelled
a barrier effect independently from road mortality by varying the
probability with which individuals avoid crossing roads. Both road
mortality and the barrier effect caused population isolation. While road
mortality alone had stronger negative effects than the barrier effect
without extra mortality, the latter also resulted in decreased
population size. Yet, road avoidance could, in some cases, rescue
populations from extinction. Populations with a large dispersal distance
were more negatively affected as road mortality increased. However, when
there was no road mortality they maintained larger sizes than
populations with a short dispersal distance. Our results highlight the
much higher relative importance of road mortality than the barrier
effect for population size and persistence, and the importance of
assessing relevant species traits for effective long-term transportation
planning and conservation management. Our model can be used in
species-specific situations and with real landscape configurations in
applications such as conservation planning.
Tags
Individual-based model
behavior
connectivity
models
Dynamics
Roads
Mortality
Mechanisms
Protocol
Future
Extinction
Forest
Abundance
Avoidance
Barrier effect