Field Test of GonaCon™ Immunocontraceptive Vaccine in Free-Ranging Female Fallow Deer

Abstract

Resident populations of two exotic deer species, fallow deer and axis deer, are having adverse impacts on their habitat and on native plant and animal communities at Point Reyes National Seashore (PRNS) in California. These non-native cervids were released intentionally for recreational hunting on the property now known as PRNS during the period 1942-1954. Approximately 860 fallow deer and 250 axis deer now inhabit PRNS. Under an approved non-native deer management plan, fallow and axis deer populations will be removed from PRNS by 2021 via culling of animals by sharpshooting and by treatment of some of the female fallow deer with GonaCon™ Immunocontraceptive Vaccine. During July-August 2007, 69 fallow does were captured, equipped with numbered ear tags and radiotelemetry collars, and injected with GonaCon™ vaccine before being released. Control animals include 10 does that were captured, marked, and given “sham” injections during July-August 2007, and 19 does that were captured and marked (but not injected) during 2005. Reproductive activity, as indicated by lactation and fecal concentrations of progesterone among the GonaCon™-treated and control does, will be monitored and compared for two years, and will be used to determine the efficacy of GonaCon™ as a cervid contraceptive agent. Traditional methods of population control, such as regulated harvest by licensed hunters, often are impractical or illegal in settings such as national and state parks, and the use of firearms may be prohibited in some urban and suburban environments. The development of safe and effective wildlife contraceptives such as GonaCon™ is needed to control locally overabundant populations in situations where traditional management tools cannot be employed.