Development of Future Habitat Suitability Models for the Swift fox (Vulpes velox) in the American Southwest

Jennifer Redman,Kenneth Boykin,Michael Calkins,Mark Andersen

doi:10.1038/npre.2009.3717.1

Abstract

AbstractThe Swift fox (Vupes velox) is a habitat specialist species of short or mixed grass prairie. We used bioclimatic envelope models and habitat suitability models under three future climate scenarios (based on CO2 emission rates) from "www.climatewizard.org":http://www.climatewizard.org to fit species distribution models, using the maximum entropy method. Current suitable habitat for the swift fox covers an area of 161,984 km2. Under the future climate scenarios the habitat decreases by 27% in the low emission scenario, 63% for medium emissions, and 53% in the high emissions scenario. This decrease in suitable habitat corresponded to an overall decrease in total grassland landcover. The current total area of grassland is 423,440 km2. Under the future climate scenarios the grassland decreased by 12% in the low emissions scenario, 24% for medium emissions, and 16% in the high emissions scenario.

Highlights

Swift fox populations have been decreasing at least since the mid-1980s (Kamler, 2003)
The high emissions scenario resulted in a 53% decrease in suitable habitat (75,520 km2), the medium emissions scenario resulted in a 63% decrease in suitable habitat (59,264 km2), and the low emissions scenario resulted in a 27% decrease in suitable habitat (118,032 km2)
The areas that were defined as suitable habitat types for the Swift fox were grassland herbaceous, montane mixed steppe shrubland, and grassland juniper woodland

Summary

Introduction

Swift fox populations have been decreasing at least since the mid-1980s (Kamler, 2003). Our approach was to compare and combine bioclimatic envelope models, which directly use climatic variables that are influential in determining the range of the species of interest, and gap-analysis habitat suitability models, which predict the species’ distribution on the basis of environmental variables such as vegetation/landcover type, elevation, slope, and aspect. Since both of these modeling approaches may lead to some overprediction, the two models were combined to produce a final model of future swift fox habitat

Methods

Results

Conclusion