Population Composition and Diets of Predators (Graduate Project)

Project Team: Brian Schoch (Graduate student), Mike Conner and Bob Warren (Co-investigators)

Project Summary:

The necropsy data from harvested predators as part of the predator control and gamebird restoration project will be used to determine changes in population composition and diets of predators in response to predator removal. Intensive harvest generally changes the age distribution and reproductive output of the harvested population. Intensively harvested populations are often skewed toward younger animals and animal age is known to influence their diet and movement patterns. Younger predators generally move over larger areas and consume prey that requires less skill to capture. Furthermore, many predator populations are self-regulating and, in good habitat, a reduction in predator populations is generally followed by increased reproduction. Therefore, assessment of age structure, nutritional condition, and reproductive output of predators in response to predator removal is valuable for assessing the overall value of the removal effort and may prove useful for explaining responses of prey populations to predator removal.

There have been a number of predator diet studies conducted in the Southeast, but relatively few diet studies have occurred on lands specifically managed for quail. This project involves the removal of all mammalian carnivores, yet other species (e.g., gray rat snakes, cotton rats, etc.) are also known to be major nest predators. There is evidence that top carnivores suppress smaller predators, which results in increased faunal diversity. The role of apex predators (e.g., bobcats and coyotes) may be especially important in reducing nest predation on native birds. Most land managers, however, consider all mammalian predators to be a threat to quail. Research is needed to document the diet of mammalian predators on areas managed for quail. Ultimately, these data will permit assessment of both the positive and negative impacts of each predator species on wildlife community diversity and abundance.