Tracking Studies Reveal Surprising Habits of Five Mature Deer
White-tailed deer hunting has evolved over the years in a multitude of ways: our tools, goals and strategies for hunting are far different today than they were 30 years ago. The advent of game cameras and their rapid growth in popularity has been a major contributor to this evolution. Hunters today have the ability to peek into the deer woods without disturbing their quarry. They can gather information on movement patterns, feeding times and herd quality with minimal effort.
As a result, deer hunters today have a much greater understanding of the activity and behavior of deer in their areas, and that translates into greater success when hunting. However, it’s important to understand the limits of this knowledge, and that having a few pictures of a deer might mislead you into thinking you understand how, when and where a deer is moving.
Over the years, I have been involved in a number of research projects where we’ve put radio collars on deer to study mortality and movement patterns. I’ve spent countless hours collecting and analyzing movement data, and have learned during that time that deer movements are extremely unpredictable. They are so unpredictable, in fact, that I’ve come to believe that deer hunting is still comprised of 90 percent luck — you either picked the right stand that day or you didn’t.
You might be able to influence or control the 10 percent of the hunt that isn’t luck, but you are still at the mercy of countless factors that are out of your control. This article is intended to describe some of the unpredictability in deer movement patterns that I’ve seen over the years.
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Specifically, I’ve selected five deer that I studied back during the 1990s in Oklahoma, and will explain the patterns of these individuals. This research was conducted at the McAlester Army Ammunition Plant in McAlester, Oklahoma, from 1995-97.
If you think like I used to, then you probably imagine that a buck establishes a home range and tends to stay in that area for his entire life. The average home range of a buck varies from about 600 to 1,200 acres, and that deer spends the vast majority of its time in that range. Of course, articles, such as the one my former student Todd Jacobsen and I wrote for the October 2016 issue of Deer & Deer Hunting on excursions, have shed light on the fact that deer wander outside of their home ranges more frequently than we think. But, for the most part, we still tend to believe that these deer will have a set home range to which they have some loyalty, and some deer do behave this way.
Deer 38: Happy Homebody
Deer 38 from our McAlester study is a classic example of a buck that was extremely loyal to his home range. This deer was captured and collared when he was 1½ years old, and we were able to follow his movements when he was 2½, 3½ and 4½ years of age. During that time, he covered an area that was approximately 1,100 acres in size, and we never once found him outside of that area.
Every year, his breeding season home range was in the same location, but it did become smaller as he grew older, likely due to the fact that he became more dominant and didn’t need to travel as far to find breeding opportunities (this pattern was apparent with most of our collared deer).
I believe the pattern this deer exhibited exemplifies how most of us think. And, if you consider most hunting philosophies, they will support this notion. If you let this deer walk, there is a good chance you’ll have an opportunity to harvest him next year. However, as I indicated earlier, deer are anything but predictable, and these next examples will make that very clear.
Deer 41: Wandering Wallhanger
Deer 41 was the stud of our research. He grossed 177 Boone and Crockett points when he was captured at 6½ years old, and we followed his movements when he was 7½, 8½ and 9½ years of age. While this deer was definitely a very dominant individual due to his large size, he tended to utilize different areas in successive breeding seasons. Specifically, each year he would spend most of his breeding season in different sections of his home range. In 1995, he primarily utilized the western section of his home range, in 1996 he spent most of his time ½ to ¾ of a mile south of that area, and in 1997 he rutted primarily at the northern edge of his home range, which was 1½ miles north of where he spent 1996.
This strange pattern of shifting his breeding range annually could have serious implications for hunters. Obviously, nobody in their right mind would pass up a 6½-year-old, 177-inch buck. But, imagine if he had been 120 inches at 3½ years old, and you passed him up to let him grow. There is a very good possibility that you wouldn’t see him the next year during the hunting season, even though you might have picked him up on your trail cameras prior to the breeding season.
Most of us aren’t fortunate enough to own 1,000 to 2,000 acres, which is what would be required to encompass the area that this buck utilized during those three breeding seasons. This means that someone else would have potentially reaped the reward of your desire to let him grow another year. Of course, the opposite is true as well: You might be seeing bucks this year that you didn’t see last year, but one of your neighbors was generous enough to pass up.
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Deer 77 & 79: Relocation Twins
The next two animals I’m going to discuss displayed very similar spatial patterns to one another, yet far different from what we saw with any of our other study animals. Deer 77 and 79 were captured together (along with one other mature buck) in January of 1995. Deer 77 was a 4½-year-old that grossed 126 Boone and Crockett points, and Deer 79 was a 5½-year-old that grossed 139 Boone and Crockett points.
We were able to follow both of these deer for the next three years. What was interesting about these animals was that they chose to spend the growing season (May-August) in different areas than where they spent the breeding season. Their breeding season home ranges were both approximately 800 acres of prairie grassland, brush and woody draw/bottomland hardwoods. Deer 79, during the three years that we monitored his spatial patterns, would travel approximately 1½ miles south from the center of his breeding home range to a totally separate area. His summer home range each year was approximately 300 acres, but the habitat was almost identical to the area in which he spent the breeding season.
The pattern exhibited by Deer 77 was almost identical to that of Deer 79. His breeding season home range was very similar in size and location to that of Deer 79, and he shifted to a completely new area each spring/summer. However, in contrast to Deer 79, the habitat that he utilized for his summer range was much different from the area he used during the breeding season. Instead of a prairie/brush type of habitat where there was considerable vegetation on the ground, he spent most of his summers in an area that was interspersed with forested upland and bottomland hardwoods. Additionally, the centers of his summer and breeding home ranges were separated by approximately 4 miles.
To this day, it’s difficult to explain why these animals shifted their home ranges so dramatically, and predictably, each year. If they had both shifted habitat types between home ranges, and they did it in a similar fashion, it could possibly be explained based upon nutritional needs. But because they both shifted to very different habitat types for the summer, it’s very difficult to explain based upon food availability or habitat quality, especially when both summer ranges and their shared breeding season home range each contained healthy deer populations with extremely high-quality animals.
It’s possible that the shifts had something to do with inbreeding avoidance. Without question, these deer wanted to be in different areas to breed than where they spent the summers, and I just described previously why I don’t believe that desire was based on nutrition. So this tells me that the deer were likely not shifting to their summer ranges, but rather were shifting away from their summer ranges for breeding purposes. This makes me think that they might have dispersed to their breeding ranges between 1 and 1½ years of age (as male deer tend to do), and then shifted back to their natal range following the breeding season and continued this pattern annually. Of course, this is pure speculation.
But I do believe that there is a take home message here. While this pattern might not be the norm, it is not necessarily uncommon, especially considering that two deer that we captured at the same instant exhibited the same pattern. As a hunter/manager, this has implications for you. If you conduct preseason camera surveys, some of the deer you catch on camera might not be there once the hunting season begins — and vice versa, there might be deer wandering your area during the hunting season, but they might have spent the summer as far away as 5 miles. While this might not account for the majority of the deer that use your property, it’s important to keep in mind for any preseason planning.
Deer 85: Shy Guy
The final pattern that I wanted to discuss was exhibited by Deer 85, a 101-inch 3½-year-old buck. This deer was nothing special from an antler size perspective, but he was definitely wise regarding what it took to avoid hunters. We trapped and radio-collared him on a food plot approximately 200 yards from the perimeter of the military base, and the area off base was heavily hunted because of the density of high-quality deer on the installation.
While there was deer hunting on the installation, it was limited to six weekends of low density traditional archery, and the area that he inhabited had very limited hunting pressure. What was interesting about his spatial pattern was that during the three years we monitored this deer, we never once located him off base property, even after dark.
The habitat on the base that he inhabited was the classic post oak-blackjack oak of the eastern Oklahoma Cross Timbers Eco-region, and there was minimal human disturbance away from roads. However, across the three-strand barbed wire fence that marked the installation boundary, the land area was comprised of the typical Oklahoma cattle/agricultural complex interspersed with hardwood drains and woodlots.
When driving the perimeter of the base, we would sometimes see him within 50 yards of the edge of the base, often during hunting season. But he seemed to recognize the relative safety of the low-pressure base property. His home range was approximately the same size (in area) of that of other bucks, but it was long and compressed, with the eastern edge abutting the base perimeter. Like the other patterns that I described, this one also has implications for how we manage/hunt deer. This buck was able to sense the relative pressure/safety of two different areas, and he avoided high hunting pressure. If you’re going to improve your abilities as a hunter, you need to do the same. Hunt those areas that are low pressure — areas with minimal disturbance that are likely utilized as refuges by mature deer. Avoid falling into the trap of most hunters who create (and hunt in) areas of high hunting pressure that are easily detected by deer.
The overall message is this: Expect the unexpected when it comes to deer patterns of space use. What you likely envision regarding the home range of a deer is probably not close to reality. Deer exhibit a wide variety of activity patterns, both temporally and spatially, that can wreak havoc with carefully laid hunting plans. But, if you keep in mind that many deer exhibit spatial patterns that are sometimes very difficult to explain, then you won’t find yourself locked into a hunting strategy that is destined for failure.
— Dr. Steve Ditchkoff is a professor in the School of Forestry and Wildlife Sciences at Auburn University. He manages the deer research program at Auburn and has been conducting research on white-tailed deer for 25 years.