Wildlife Damage Management, Internet Center for


Date of this Version

April 1987


Bullsnake (Pituophis melanoleucus) predation on upland nesting ducks was monitored on Valentine National Wildlife Refuge (NWR) from 1982-86. The fate of 1,999 duck nests of 9 species was observed under different treatments of land use and control of potential nest predators. Maximum potential levels of bullsnake depredation are masked by nest destruction by mammalian species; bullsnake nest depredation rates were >65% where mammalian predators were controlled, >40% without predator control and <4.0% where both mammalian and reptilian predators were controlled and/or excluded. Duck nest densities were dramatically increased where predator control was accomplished in undisturbed nesting cover.