Spatiotemporal occupancy patterns of chronic wasting disease

Area of Science:

• Wildlife ecology
• Disease ecology
• Environmental science

Background:

• Chronic wasting disease (CWD) incidence and geographic spread are increasing in Kansas cervid populations.
• Understanding CWD occupancy patterns is crucial for effective management strategies.

Purpose of the Study:

• To assess the occupancy patterns of CWD in white-tailed deer and mule deer across Kansas.
• To identify environmental factors influencing CWD distribution.

Main Methods:

• Utilized a dynamic patch occupancy model within a Bayesian framework with surveillance data from 2005 onwards.
• Incorporated 13 principal components representing habitat, soil, and elevation as environmental covariates.
• Selected the best model using Watanabe-AIC and AUC values (0.89).

Main Results:

• The model indicated a consistent eastward and southeastward progression of CWD in Kansas.
• Random forest analysis revealed geographic location, elevation, mixed forests, and soil attributes explained 96% of variability.
• Key soil attributes included pH, clay content, depth to restrictive layer, available water content, and bulk density.

Conclusions:

• This study provides the first comprehensive analysis of CWD occupancy in Kansas.
• Findings align with previous research in other regions, supporting their utility for surveillance and management.
• Environmental factors are critical determinants of CWD spread and distribution.