September 22, 2010
A few years back, I was part of a team of scientists asked to write a book on whitetail management. Each of us was to write a chapter or section dealing with our area of expertise. When we were done, I was amused to see most chapters begin with the admonition, "Do not try this home. Consult a professional biologist."
Not long after that, I presented a series of talks in a state in the Southeast. Before it started, the fellow putting on the tour lectured me on how I should present my talks. "These are simple folk," he warned. "You have to talk to them at a third-grade level."
I ignored his advice and gave a presentation along the same lines as I'd done many times over the years. Then I asked for questions.
"Yes," queried one participant. "Can you tell me how to obtain infrared aerial photographs?"
Another chimed in, "While you're at it, do you have your talk on computer, so I can show it to the other members of my hunting club?"
So much for that perceived "third-grade" mentality!
The fact that someone hasn't been "anointed" in the wildlife management profession doesn't mean he or she is incapable of understanding at least some of the complexities of wildlife science. In fact, more of you than ever now are talking to each other and to us professionals about the results of your own research.
The spirit of science is to search for the truth, not to substantiate a theory. A good scientist always goes about his business with a skeptical and open mind. There's no such thing as the right answer, only an answer. In short, if you're going to get involved in amateur science, start now to rid your mind of all preconceived ideas you might have about deer.
The scientific method, which has served us well for many decades, follows a few simple steps: (1) observation of a phenomenon; (2) formulation of a hypothesis to explain it; (3) analysis of the data; and (4) evaluation of the results. All are important to good science.
A good deer scientist is a keen observer. You'd be amazed at the number of wildlife students who can be at my side and never notice the things I see. It's not that I'm so much smarter, only that I'm more experienced in deer observation.
I'm a fanatic about record keeping and over the years have urged many of you to keep records on your deer herds and hunting efforts. In a similar way, a good scientist always keeps a journal of his/her experiences in the field. A small notebook or diary is a great tool to the deer enthusiast; in fact, the very act of taking notes causes you to become more observant. Accumulations of notes lead to ideas, which can in turn lead to fun research.
Granted, some study methods don't lend themselves to the layman. For example, it's not in your reach to conduct radio-tracking studies; the equipment is far too expensive, and most states don't permit the public to engage in such work. On the other hand, there are many studies you can do easily, as we'll discuss.
A good experiment has the following characteristics: (1) It can be replicated by others; (2) it has a sufficient sample size; and (3) it is free of bias. Let's look at each of those traits.
In order to be replicated, an experiment's methods must be clear to anyone who tries to duplicate the work. Science is also based on repeated experiments by other scientists in order to test the original results. So, if you discuss the results of your work or write about it, your methods must be clearly stated, so others can test your results in their areas.
Sample size is important as well. There's not much credibility to a single observation! The more times you repeat an experiment, the more faith you can have in your results. Of course, this isn't true if you violate the next rule: the one that states an experiment must be free of bias.
Even research conducted by experienced scientists can be full of unintentional, and sometimes intentional, bias. If you set up an experiment incorrectly, or worse, cheat on the results, you can "prove" just about anything. Always try to free yourself of such weakness.
I'm convinced an "army" of amateur scientists can contribute a great deal to the world's pool of whitetail knowledge. In fact, as I write this, someone out there has made an observation that, if tested properly, would lead to a significant new discovery about whitetails.
While complicated research projects such as radio-telemetry aren't in the reach of the most readers, the advent of some new technologies does provide you the means to learn a lot about deer behavior.
In deer research, perhaps the most significant development since radio-telemetry has been the infrared-triggered camera. Thousands of these are being bought by laymen every year; unfortunately, most owners of these devices limit themselves to what can be learned. The cameras can tell you a whole lot more than just which buck is using which trail.
We pioneered the development and use of these instruments here at the Institute for White-tailed Deer Management & Research and have applied them to a host of studies, including scraping behavior, activity patterns, use of various food items, etc. Many of our studies really need replication by those of you who'd like to get involved. Here are a few questions you can try to answer:
One of the worst ways to learn more about this important subject is to rely on observations made from your stand or blind. The presence of humans grossly affects deer behavior. Infrared-triggered cameras reduce the bias created by human presence. They're out there "24-7," as the technocrats say, always watchful and with hardly any disturbance. So, proper use of the cameras can give you a very good idea about deer activity on your property.
The more cameras you use, the more accurate your results. Fortunately, camera prices are falling, so it's becoming easier to set up a good number of them. But a lot can be learned, even with two or three.
The world's largest gathering of whitetail researchers is the annual meeting of the Southeast Deer Study Group. Each year, several hundred university researchers, graduate students, resource-agency managers and other interested persons attend to share the results of their deer-research efforts. Chattanooga, Tennessee, will host the next such meeting in February 2003.
Distribute cameras randomly about your property, but locate them within what you think is good deer cover. Whether or not you use bait is debatable. You can just put the cameras along trails or place them over-looking piles of corn. (Note that some states allow baiting at any time, others prohibit it during certain parts of the year, and others prohibit it year-round. Check the law before conducting any study using bait.)
We've found that two weeks is long enough to get an unbiased estimate of deer activity patterns. Most commercial units allow you to print the time on each photo, which is important; you want to determine when deer are actively moving or feeding.
Once you've accumulated all your photos for the study period, record the time each photo was taken and the number of deer in each photo. You also can break up the data by sex and relative age (buck, doe, fawn, immature buck or mature buck). Then construct yourself a graph similar to the one illustrated, with the percentage or number of events on the Y- (vertical) axis and the time of day along the X- (horizontal) axis.
When you have an activity pattern graph established, try some experiments. One we enjoy is to see what happens to buck activity as the rut or hunting season approaches and ensues. Does the pattern change? When are bucks most active then? If you have enough cameras to move them around, where are bucks active before opening day versus afterwards? The number of questions to be answered is limitless.
RUB & SCRAPE STUDIES
How many bucks use the same rubs and scrapes? There's an easy way to find out: place a camera where it can spy on them.
Our camera studies suggest bucks tend to return to the same areas year after year to mark their territories. You can obtain answers not only to the above question but also can learn when bucks begin to use rubs and scrapes. How about comparing this time over the years? And do bucks in your area begin breeding activity at the same time each year?
In the spring, use cameras to determine when the does show up with their fawns. Generally, fawns undergo a "laying out" period during which they don't move. This lasts about two weeks, after which they begin traveling with their mothers.
We use fawn observations to determine how distinct the birthing period is, which gives us clues as to how the deer are doing physically. A tight fawning period reflects a herd in good condition; spread-out fawning says something is wrong. Likewise, the number of fawns observed per doe further supports a health assessment of your herd.
AGE STRUCTURE & SEX RATIO
Our early research with Dr. Harry Jacobson of Mississippi State University showed we could assess the age structure and sex ratio of a herd with a two-week camera census. But be careful. At well-established feeding stations, cameras tend to bias the sample toward bucks, which dominate feeders. Placing cameras along trails and over newly established bait piles reduces this bias.
Take a close look at all your photos. Record the number of total photos (even repeats) bucks, does and fawns; then calculate the percentage of each. Buck:doe and doe:fawn ratios can then be calculated. With practice, you can learn to age bucks in the photos. Separate your data into at least three basic buck age classes: yearling, immature and mature.
One of the most common questions about deer involves what to plant for them. At our institute, we test almost every variety of food-plot forage on the market. Some pan out; others fail miserably. No single variety will grow everywhere and under all conditions, so it's beneficial for you to conduct your own research.
The best way to test acceptance of a food-plot planting is to employ what we call the "salad bar" technique. We literally lay out a buffet of several varieties from which the deer can select. A plot size of 10 feet by 20 feet for each variety is more than adequate. (Leave a foot of space for walking between them.)
Use two or three replications of each variety, placed at random. There are fancy ways to ensure this, but an effective one is to write the number of each plot on a piece of paper and place the pieces in a hat. Do the same with the plant varieties. Then draw them one by one, matching the variety to the area of the plot. This will give you unbiased plantings.
To be sure you don't bias the results during the actual planting process, prepare the entire area the same way before marking off your plots. Determine the amount of fertilizer and lime (if needed) by a soil analysis obtained from your local Agricultural Extension Service agent.
After planting, place an exclusion cage at a random location in each plot. Construct these from 2x4-inch welded wire and make them 2 feet in diameter. Stake the cages down with a length of rebar or a T-post.
The simplest way to tell how well deer like each variety is to measure the difference in height between what's inside the cage and what's outside. This gives a relative-use figure. To learn even more, each month clip all of the above ground plants from a 1-foot-square area selected randomly, place the material in a paper bag and immediately take it to your extension agent. Request a standard forage analysis. Farmers do this all the time with hay, so you won't be asking for anything unusual.
Be sure to ask for a report that gives you the dried weight of the material, percentage protein and standard minerals, such as calcium and phosphorus. Some labs also give you a report on the amount of indigestible fiber and total available nutrients.
Because deer are reluctant to accept anything new, repeat your tests for two years before reaching any conclusions. Also, rainfall differs; what you think is a great plant grown in a wet year might turn out to be less useful in average to dry years.
SPATIAL USE OF YOUR HUNTING AREA
Global Positioning Systems (GPS) technology has helped deer research. Fortunately, the U.S. government now permits much better accuracy for GPS units than was the case a few years ago. Accuracy to within less than 10 meters is now possible.
The author is a highly respected researcher in several fields of science. Much of his research centers around the use of technology that can help man better understand nature. In fact, as director of the Emergency Geospacial Mapping Laboratory at Stephen F. Austin State University in Nacogdoches, Texas, Dr. Kroll is leading the effort to map the massive debris field of the space shuttle Columbia, primarily with the aid of GPS technology.
But there are some misconceptions about using these devices. They work fine for using waypoints and generally finding your location, but when you try to place features over a topographic map or aerial photo, be careful. Maps and photos from government agencies are classified according to various land-coordinate projections. Often the projection used by your unit is different from that of your map - even the ones you buy from GPS providers. This can cause your data to be offset from where it should be on your map or aerial photo.
Despite such quirks, you can learn plenty about your deer using GPS. With a GPS unit to mark the locations of rubs, scrapes and other features, you can literally "connect the dots" to show how bucks use the land. In the August 2002 issue, I discussed how we used GPS plotting of rubs, scrapes and beds to study bucks' spatial use of our research facility. GPS analysis can teach you a lot about how deer utilize their habitat.
What I've presented here are only a few of the many research projects you could do where you hunt. Your research is limited only by your observation skills and imagination. But for those who need a starting point, here are some more ideas that should keep you busy for a while:
How does neighbors' hunting pressure affect the deer you hunt?
Do the deer using your land change locations during the year?
How does acorn production change from year to year on your land?
Are deer feeding uniformly over the landscape?
Are there areas on your land where specific types of antlers prevail?
Where do most bucks shed their racks? Is it consistent each year?
Are some trails used by bucks only? Does only?
How does the time of antler casting vary from year to year?
If you decide to become a deer researcher, let those of us at North American Whitetail know what you learn. Who knows? Perhaps you will be the one to make the next exciting discovery about our favorite animal!