Data from: Heading west: Ecology of swift foxes in a novel landscape beyond their range

The swift fox (Vulpes velox) is generally associated with the short-grass
prairie ecosystem of the North American Great Plains; a system that has
declined by approximately 50% over the last century. Yet, swift fox
populations seem to demonstrate regional variation in trends, with some
populations declining while others appear stable to increasing. In
Wyoming, USA, swift foxes have been observed and successfully reproducing
over 100 km west of their historical range boundary in shrubland-dominated
habitats, previously deemed unsuitable. This has created challenges in
conservation, as it is unclear what factors are uniquely important to a
species occupying habitats previously considered unsuitable. Therefore, we
sought to investigate fundamental questions regarding swift fox ecology in
this novel habitat: (1) what environmental gradients are contributing to
suitable habitat?, (2) how is swift fox habitat suitability associated
with competitors (American badgers [Taxidea taxus] and coyotes [Canis
latrans]) in space?, and (3) how do swift foxes and competitors allocate
activity in time? Between 2021 and 2023, seven swift foxes were
GPS-collared, and 71 camera traps were deployed in central Wyoming.
GPS-collar locations paired with environmental covariates were used to
develop a habitat suitability model using Random Forest, predicting 30.28%
of our study area was suitable. Important habitat resources identified
were herbaceous biomass, shrub height, and sand content. We found swift
foxes likely have minimal spatial and temporal separation between
competitors, specifically coyotes. We hypothesize that swift foxes may
successfully coexist with competitors either by being less risk-averse for
the sake of resource acquisition or by relying on abundant escape cover,
which reduces the need to modulate spatial or temporal activity. Our
findings enhance our understanding of environmental factors contributing
to suitable habitats and how swift foxes coexist in time and space with
competitors in a novel shrubland environment. The R code is divided into
five sections: The first section employs Random Forest modeling to assess
the environmental gradients that characterize swift fox habitat in
unconventional shrublands and predict suitable habitat across the study
area. The second section validates the predicted habitat suitability map
using reserved GPS centroids and independent data. The third section
focuses on understanding trends in swift fox habitat suitability and its
covariates. The final two sections explore the association between swift
fox habitat suitability and competitors (i.e., coyotes and American
badgers) in space, as well as how swift foxes and their competitors
allocate activity over time.