If all goes well, there may soon be a new tool for humanely controlling "nuisance" black bears.
The HSUS is pleased to report on our black bear immunocontraception pilot project at Six Flags Wild Safari, adjacent to the Great Adventure theme park in Jackson, New Jersey.
In October, six female black bears were chemically immobilized, microchipped, ear-tagged, and inoculated for contraceptive purposes at the Six Flags facility. Four of the bears were treated with the contraceptive agent known as porcine zona pellucida, or PZP, while two other "control" bears were treated with a placebo. In November, all six females were recaptured to gather data. Capture and treatment during the two phases went very smoothly, and no bears were injured. Each bear will be monitored on a daily basis beginning early this spring to document cub production, mating, and other information.
The PZP vaccine used in the study was previously tested on bears at the Bear Country USA wildlife park in South Dakota, and none of those bears became pregnant. The vaccine has been used to successfully treat other species—including deer, horses, and elephants—in a number of previous trials. PZP is derived from tissue that comes from pigs that have already died. When the substance is injected into some mammals, their bodies treat it as a foreign invader and create antibodies that attach to females' eggs like armor, blocking fertilization.
The injection has no effect on existing pregnancies. Since the treated Six Flags bears may have already been pregnant with cubs to be delivered this spring, no information on the effectiveness of the vaccine will be available until early next year. The project is a cooperative effort involving The HSUS, Six Flags, the New Jersey Department of Environmental Protection, and the Tufts University School of Veterinary Medicine.
MARO staff are delighted to see this cutting-edge technology moving forward, and hope it will be a useful complement to the development of non-lethal techniques to resolve conflicts with native wildlife populations.
