Assessing Gray Fox Population Declines

Assessing Population Declines of Gray Foxes in Indiana

Gray foxes are a valuable and understudied furbearer not only in Indiana, but generally across its entire range. Several indices strongly suggest declining populations in Indiana, but also other Midwest states. The cause(s) of these declines is unknown, but may be linked to habitat loss and fragmentation, changing mesocarnivore (e.g., coyote) community structure, disease, and other factors, and likely is a complex relationship among these factors. During 2020–2023, we are implementing a large-scale, comprehensive study at two study sites in Indiana, with objectives designed to directly assess causes of declining populations of gray foxes, and to provide recommendations for management of this species that can be applied in Indiana, but also other Midwest states.

Geriann Albers (Indiana Department of Natural Resources) and Dr. Dawn Reding (Luther College) are providing critical expertise as collaborators on this project.

Based on observations obtained during the archer index, there is evidence of a long-term declining trend in the statewide population of gray foxes in Indiana.

Our project study area includes two study sites: central (Bartholomew, Decatur, and Shelby counties; primarily agriculture and private lands) and southern (Crawford, Harrison, Orange, and Perry counties; primarily forested with public lands) Indiana, USA. Red = all developed-area cover types, yellow = cultivated crops, and green = all forest-cover types.

What does this substantial effort include?

Capturing and GPS-collaring 40–70 gray foxes in two multi-count study sites in Indiana
Assessing survivorship and cause-specific mortality, including an attempt to assess pup survival
Determining space use and habitat selection of gray foxes
Modeling potential gray fox habitat in Indiana using Maxent software
Assessing diseases and parasites of gray foxes
Conducting diet analysis
Evaluating gene flow and identifying potential genetic barriers

Although this is already a major project, we are also looking into ways to expand the project, both spatially (other Midwest states) and through additional field techniques to meet our objectives.

Learn more about gray foxes in Indiana on the Indiana Department of Natural Resources web page here.

Stay tuned for project updates!

Project Partners