Comparing landscape suitability and permeability with and without migration data: the influence of species movement behavior

Authors: AZITA REZVANI, SHIMA MALAKOUTIKHAH, SIMA FAKHERAN, ALIREZA SOFFIANIAN, MAHMOUD-REZA HEMAMI, JOSEF SENN

Abstract: Maintaining landscape connectivity through identifying movement corridors is the most recommended conservation strategy to reduce the negative impacts of habitat loss and isolation. The basis of most connectivity modelling approaches for modelling corridors is that species choose movement pathways based on the same criteria they used to choose habitats. However, species behave differently in using landscape elements for moving than for selecting habitat. In other words, suitability of a given landscape feature may differ between moving and habitat use stages. In this study, we evaluated how the availability of migration occurrence points for wild sheep (Ovis orientalis) could affect the outputs of distribution models and consequently the strength and extent of landscape connectivity for migratory movements of this species in central Iran. We employed concepts of Maximum entropy and circuit theory and developed 2 groups of habitat suitability and connectivity models with and without migration data. Comparing the results of the developed models showed that the main differences in the outputs of MaxEnt models were associated with suitability values predicted for the unprotected migration habitats. Without migration occurrence points, MaxEnt did not identify the traditionally used migration habitats. In contrast, Circuitscape represented a similar performance in predicting the main migration corridor of the species when using or not using the migration occurrence data. These differences could be associated with wild sheep's different behavior in the selection of habitat during movement and home range stages. Owning to this difference, we suggest using migration data in modelling landscape connectivity as these data may include different environmental conditions to those collected from home range habitats. For wild sheep, we recommend protecting the migration corridor at least during migration time. Maintaining such connectivity would also largely depend on managing the unprotected matrix through preventing expansion of human land uses in the vicinity of the corridor and buffering it to some distance.

Keywords: MaxEnt model, habitat security, landscape permeability, anthropogenic threats, current flow, functional connectivity

Full Text: PDF