Each fall, in hunting camps around the country, hunters converge after morning and evening hunts to swap tales of the days events and plot strategies for the next hunt. At some point the conversation inevitably comes around to the status of the local deer population. Hunters share their opinions on things like deer density, sex ratio and age ratio, particularly of the bucks. We all have opinions, sometimes strong, but without hard data, it’s little more than speculation. Wouldn’t it be nice to find out what you really have on your property?
Fortunately, you can; and it can be done relatively easily and inexpensively, particularly if you’re already doing some type of supplemental feeding. Then all you need is a few trail cameras – probably fewer than you think.
Mississippi State University researchers Dr. Stephen Demarais, William McKinley and Dr. Harry Jacobson developed and refined an infrared-triggered camera survey technique that can provide a bunch of useful information on your deer herd, with a surprisingly small investment in time and equipment. Results will provide an accurate survey of your local deer population, especially when used in conjunction with observation data, harvest data and habitat evaluations.
How Many Trail Cameras?
Initially, you might think the expense of cameras alone would be cost prohibitive. According to research however, one camera per 100 acres is sufficient. If you’re like most hunters nowadays, you probably already have a few. Just add as many as you need to meet this ratio.
When To Put Trail Cameras Out?
For optimum results you should conduct two surveys, one just before hunting season, and another just after. Exactly when will depend on when your seasons occur, but you can begin as early as late August and end as late as early February.
Where To Put Trail Cameras?
Begin by laying out a map grid of your property – on an aerial photo or topographical map – divided into approximately 100-acre blocks. Then place one camera in each block. They need not be evenly spaced. It’s more important that you place cameras in areas heavily utilized by deer. Two-tracks, skid roads, the edges of food plots or agricultural fields or heavily traveled deer trails are ideal.
This is where supplemental feeding comes in. If you haven’t already done so, establish feeding stations as part of your regular supplemental feeding program, one per each 100-acre block. Heartland Wildlife Institute has several nutritional supplements you can use. It would be advisable to use a combination of Rack Maker Deer Block and a loose feed, like Autumn Addiction or End of the Trail Mix. These will also be your camera stations. Record a GPS way point, then plot each station on your map.
Make sure your cameras are working properly and loaded with fully charged batteries. Set all of cameras to record date and time of each photo. Also, set all cameras on a 10-minute delay to avoid an unnecessary glut of images. Face camera North or South to avoid backlighting, and clear all vegetation from the detection zone to prevent false events.
Pre-bait for at least five days. If you’re supplementally feeding, you’re likely already doing so. Be sure to check the baiting laws in your state to make sure it is legal. You’ll be conducting your survey outside of the hunting season, but it’s still a good idea to be sure.
How much food you need will depend on several variables, including how many deer you have, and how hungry they are. Make sure there is feed at each station throughout the survey period.
How Long To Leave Trail Cameras Out?
Short survey periods of 5 to 10 days are adequate, but you’ll achieve greater accuracy with a longer 10- to 14-day survey. This should ensure you are photographing close to 90 percent of both bucks and does.
Deer Survey Analysis
Once your survey period is over, compile all of your photographs and carefully count the number of bucks, does and fawns.
For bucks, count: 1) total number of bucks in the photos, including repeats; 2) actual of number of individual (unique) bucks. This is most easily done using antler characteristics such as number of points, abnormal points, tine length, spread or other distinguishable antler or body characteristics. Exclude any deer that are unidentifiable from the survey (there will usually be a few). The result will be your buck population.
For does and fawns, count the total number of does and fawns in the photos, including known repeats.
Estimating (and yes, this is an estimate) the number of does and fawns takes a few simple calculations. Take the number of unique bucks (#2 above) and divide this by the total number of bucks photographed (#1 above). Then multiply the resulting population factor (#2 divided by #1) by the number of does and fawns counted in the photos. That’s it.
From this information, you can also calculate a buck:doe ratio and a fawn:doe ratio. If you’re skilled enough, you can even take a stab at aging the bucks, then sort them by age class to determine age structure. Repeat the survey over multiple seasons allows you to observe trends, which can be more valuable than an actual population estimate for any given year.
For more information on precisely what Heartland Wildlife Institute supplements to use, check back for future installments, or scroll through the archives of this series.
Acknowledgments: Jason R. Snavely, Drop-Tine Wildlife Consulting, Millville, PA; The Quality Deer Management Association; Dr. Stephen Demarais and Dr. Harry Jacobson, Mississippi State University; William McKinley, Mississippi Department of Wildlife, Fisheries and Parks.