Most deer management programs start with “How many deer are there?”
Our population estimates can help with the answer.
Population estimates are not an exact science because there are numerous factors that can create an error in any method. They often provide a minimum count or can help track population trends. Deer are sentient and highly mobile animals whose movements and behaviors differ by day, night, and seasonally, making an absolute count of all individuals challenging. With this said, an initial survey can be helpful in the deer management plan development phase to obtain a better understanding of the relative scope of the problem. If management action is taken, an additional measure of success is an impact-oriented approach: management effort is increased to the point at which conflicts, such as deer/vehicle collisions, reach tolerable levels, then the same amount of effort would be required to maintain deer densities. Be aware that regardless of the methods used and the qualifications/experience of personnel conducting such surveys, results often are contested and deemed “junk science” by those whose beliefs or perceptions are not supported by the data.
White Buffalo Inc. has found that the distance sampling method, where you drive a pre-designated route and spotlight (and/or use thermal imagery) to count deer and measure their distance from the road, works very well in suburban environments. Helicopter counts over snow and aerial FLIR counts tend to work better in larger undeveloped areas. If there are individually marked animals present, for example, associated with a research project, another method that uses the ratio of marked to unmarked animals can provide accurate estimates. The final method that is credible to estimate deer densities is using IR cameras to systematically take pictures and then extrapolate the images into a population estimate. We also will teach cooperators how to perform the various methods and/or interpret the results to have a better baseline for their deer management program.