Many communities are hoping for a non-lethal solution to conflicts that have cropped up in areas where there are over abundant white-tailed deer. Over the years, White Buffalo Inc. has conducted research on a variety of immuno-contraceptive vaccines, ranging from GonaConTM and SpayVacTM to PZP (for detail: Fertility Control Research). In 2009, we began to transition from vaccine research to surgical sterilization. The vaccine technology had stagnated and no vaccine was (is) available that met basic requirements for practicality – it would need to work on most females and a single injection would need to be long lasting. We have optimized a method for field sterilization, and since 2009, we have performed over 500 surgeries and trained 11 veterinarians. Overall, mortality has been extremely low. We have documented only one confirmed case of internal bleeding caused by "surgeon error" and we have since refined our ligation procedures. Other mortalities were the result of pre-existing conditions or "normal" capture-related mortality. This surgery is similar to, but less invasive than, a dog or cat spay. We are simply removing the ovaries vs. removing the ovaries and the uterus (for detail: Surgical Sterilization 1-sheet).
This method is still considered research by many States because there are still unknowns. We are working to determine the scope (i.e., management area size) at which this method has utility, the costs associated with the method with "all professional" versus partial volunteer involvement, funding sources, and immigration impacts on demographics of open suburban deer populations. These data will serve as a benchmark for what can or cannot be done (and the associated cost/labor) from a management perspective with a "nonlethal only" approach to white-tailed deer management. There are many misunderstandings about fertility control applicability and we’d like to be able to address them with research.
We have worked in many developed settings and have found that deer abundance can become quite high even in very densely developed areas (<1 acre zoning) where lethal methods become very limited. This is where we see some potential utility for nonlethal techniques, because we can access entire populations with darting equipment rather efficiently. Obviously, if a community’s goal is to quickly reduce deer densities, some lethal efforts can be integrated.
In respect to the why this is still called research vs. a management technique, we look at sterilization as being in the transition phase. We have proven that we can successfully capture very high percentages of local populations and have minimal mortality. The remaining question is how will a local population respond over time in regard to mortality and immigration rates (we are/will be measuring this in several locations over the next 5 years). We have some assumptions about immigration based on deer behavior, but look forward to seeing the actual results.