Fig 1.
Diagram based on Johnson (1980) [6], indicating four scales of resource selection and associated application to invasive species ecology.
At the first order, species distribution (green) can be identified at the landscape scale, compared to second order selection where the location of an individual’s home range is known within the landscape. Third order selection can determine selection within the home range based on fine-scale movement behavior, and fourth order selection involves investigations into how invasive species use or disturb habitats at the finest scale.
Table 1.
Timeline for each pig equipped with a GPS collar.
Number of GPS locations acquired for each pig were tallied by season on Fort Hood Military Installation 2016–2017.
Table 2.
A priori models of covariates hypothesized to influence first passage time (FPT) and their predicted effects on GPS collared wild pigs on Fort Hood Military Installation in 2016–2017.
Fig 2.
Average three-hour step lengths (with 95% confidence intervals) of GPS-collared wild pigs on Fort Hood Military Installation in 2016–2017.
Fig 3.
Predicted effects on hazard ratios using our top cox proportional hazard model on A. Temperature, B. Season, and C. Landcover type.
95% confidence intervals are represented by grey lines (A) or horizontal error bars (B, C).
Table 3.
Cox proportional hazard model results relating first passage time of GPS-collared wild pigs on Fort Hood Military Installation, Texas, USA in 2016–2017 to explanatory variables.
Table 4.
Hazard ratios and their associated 95% confidence intervals (CI).
Confidence intervals not overlapping 1 indicate an effect of that covariate. Land cover types and seasons are categorical variables where hazard ratios are in reference to the base category. The base landcover category is grassland, and the base season is fall.
Table 5.
Seasonal variation in stomach contents is expressed as average percent volume (%V) that an item contributed to the total volume on an individual’s stomach (followed by standard error in parentheses), and the frequency (%F) at which an in item was detected at least once in an individual during a season on the Fort Hood Military Installation, Texas, USA, 2016–2017.