October 18, 2011
Gone are the days when deer hunters could only dream of the number and size of bucks using their properties. Today, they can go afield armed with photographic evidence of nearly every buck in their hunting area. Of course, I’m referring to the use of game cameras – perhaps the greatest deer hunting and management tool ever created. When used properly, they allow individual bucks to be targeted for harvest and provide valuable management information including buck age structure, herd sex ratio, fawn recruitment, and population density.
However, despite their obvious benefits, game cameras also can lead to significant frustration. Each year, camera enthusiasts across the whitetail’s range photograph mature bucks during late summer or early fall only for these bucks to disappear during the hunting season. Even more frustrating is when many of these same bucks magically reappear after the hunting season. Did these bucks leave the property or simply avoid being photographed? Thanks to several recent studies regarding buck movements, we are starting to gain answers to these questions.
Seasonal Home Range Shifts
Studies have revealed that many bucks make seasonal shifts within their annual home range. These shifts commonly occur in late winter after the breeding season and again in early autumn just prior to the next breeding season. Thus, bucks may occupy very different areas, often separated by a mile or more, at different times of the year.
Range shifts are thought to be driven by food availability and changes in buck testosterone levels. In late winter, increasing day length triggers declines in testosterone levels, antler casting and the formation of bachelor groups. The low testosterone levels allow once fierce rivals to get along like adolescent school boys. This also allows two related phenonenons known has “habitat partitioning” and “sexual segregation” to occur. Habitat partitioning refers to how bucks and does use different habitat components during the year. Sexual segregation simply describes how bucks and does remain largely isolated from each other during the non-breeding season. Together, these strategies enable bucks and does to optimize their environment for maximum survival and reproductive success.
During spring and summer, buck bachelor groups typically seek out high-quality food sources such as a farmer’s soybean field and establish small, consistent seasonal ranges around these areas. Does, however, seek out high-quality fawning areas. These areas may or may not be in close proximity to high-quality food sources or areas frequented by bucks. As day length begins to shorten in early autumn, buck testosterone levels rise, antlers harden, and buck bachelor groups disband. The once-friendly bucks are friends no more! Once this occurs, many return to their fall or breeding home ranges. And, if they survive the hunting season, most will return to their summer home range the following year.
This means that many of the bucks you photograph during late summer or early fall will not be on your property during hunting season or, at best, pass through only occasionally. This is especially true on small properties. However, keep in mind that bucks on surrounding properties are doing likewise, meaning that many “new” bucks often will magically appear during the hunting season.
Maximizing Hunting Success with Game Cameras
Given all of the “mixing and moving” of bucks across the landscape, how can a hunter determine which bucks are annual residents versus those which are only there during the summer or the breeding season? The best way is to run your game cameras year-round or at least from mid-summer through late winter. This will allow you to “capture” nearly every buck using your property during some portion of the year. Depending on local laws, the cameras can be baited (e.g., corn, food plots, minerals) or non-baited (e.g., rubs, scrapes, trails). If non-baited, more cameras – often one for every 50-100 acres – will be needed. If baited, about half this number will generally suffice.
The next step is to identify individual bucks and assign them to two broad seasonal groupings – July to late September and October to February. These groupings are based on a traditional November rut, so it could vary in your area. Placing bucks in these groups will help determine which are using your property during their “summer” home range and those using it during their “breeding” home range. Certainly, there will be some resident bucks that are photographed throughout the year. So, in essence, you are hunting two fairly distinct groups of bucks, with a third, overlapping group.
Without question, bucks using your property only during the summer and early fall are the most difficult to harvest because your window of opportunity is so brief. You better arrow them in the first couple of weeks of the archery season or kiss them goodbye until the following year. Therefore, if you photograph a large buck one year and he disappears during the breeding season only to return the following summer, don’t hold back waiting for perfect conditions. Hunt him hard and fast from the first day of the season.
However, if you photograph a buck of interest throughout the year or consistently during the breeding season, a different strategy is in order. These bucks are likely to remain in the area during the rut, so a well-designed plan-of-attack is warranted. Pay close attention to the locations where the buck was most commonly photographed, as these can provide clues to his core area. Often, time and location information from photos can be used to determine the most likely bedding areas and travel routes. Many of the best hunters I know use this strategy with remarkable success.
So, while the game camera is clearly among the greatest deer hunting and management tools ever invented, they must be used throughout the season for maximum success. However, armed with this latest Whitetail Science, you now have a better understanding of how bucks use their environment and what to do when bucks go missing.
Brian Murphy is a wildlife biologist and CEO of the Quality Deer Management Association (www.QDMA.com). He also has been an avid bowhunter for more than 30 years.