More and more landowner/hunters are taking an active role in managing deer herds, and for good reason — most state agencies don't have a clue as to what is going on out on the back 40. Deer management needs to be site specific and the only one who can do an effective job of managing your deer is you.
|A pic from a game camera shows two mature does and one button buck fawn — a recruitment rate of .5.|
This is especially true when it comes to managing deer numbers. Most hunters get it — there is nothing good about an over population of deer. They eat everything in sight and begin to decline from shortages of life giving food and cover. In extreme cases they will even disappear.
Monitoring Population Dynamics
Modern hunters willingly harvest does to keep populations in line with the habitat they live in. The trick is to harvest enough does to keep populations in check, without taking the numbers down to the point where the deer hunting suffers. To do so, you need to monitor herd population dynamics carefully and make informed decision before you ever considering squeezing a trigger.
Most state agencies at best macro manage their whitetail populations. They manage hundreds of thousands of acres at a time. This means they are generally clueless as to what is going on your personal 200 acres of paradise or for that matter 5,000 acres of public land you hunt. Deer management is best carried out on a site specific basis. Deer need to be micro managed to the point where you know exactly how many does should be harvested (or not harvested) in a given locale. That locale may be 20 acres, or 200 or even 2,000, but micro management is a must if you are going to maintain a deer herd which provides a quality hunting experience — at least as far as how many does to harvest.
It's up to you to decide if deer are eating themselves out of house and home and your numbers need to be taken down, or the coyotes have taken more than their share and you need to lay off the does until your numbers return. The state may have issued a doe tag but that doesn't mean you have to use it. Or maybe you need to come up with a few more tags and fill them.
Fawn Recruitment: The Key to Population Dynamics
And that's where the counting fawns part comes in. Not newborns, fawns that are old enough to become members of the adult herd. Deer managers refer to it as establishing the fawn recruitment rate. Said another way, how many fawns will join (or be recruited into) the adult herd this fall. Most fawns are about 4 months old by late summer/early fall. They have dodged the coyote bullet and escaped from being eaten by a bear or bobcat. Short of winding up in the grill of an 18 wheeler, if they have made it this far, chances are they will be "recruited" into the adult herd.
Recruitment rates are expressed as a ratio of fawns to adult does. To calculate it, you count the number of fawns using your property and divide it into the number of does using the same area. If you have 1 fawn for every doe, your recruitment ratio is 1.0. One fawn for every 2 does = .5. One fawn for every 3 does =.3. A recruitment rate of one fawn to every adult doe (1.0) is about average, .5 is low and a 1.5 is really high (remember, many of this years adult does were not bred as fawns last year).
Scouting cameras placed over bait is a great way to establish ratios where legal but you can get a pretty good feel for things with binoculars and a few weeks of watching food plots or feeding fields. All you do is count your does and count your fawns and divide the number of fawns by the number of does and you have it. Be sure to take multiple counts, there is statistical safety in numbers. Be sure to wait until the does are moving and feeding with fawns or you will under count fawns. They have usually joined the adult herd completely by mid-September.
Establishing Doe Harvest Guidelines
Once you get your recruitment rate, you can decide how many does to harvest this fall. A recruitment rate of about 1.0 will allow you to remove somewhere around 25-30 percent of the adult does in your population without changing herd numbers significantly. If your rate is low (.7 or lower), you may need to reduce your harvest goals or shoot no does at all if you want to keep the same population numbers on your property constant. Higher than 1.3 or so you may have to increase the doe harvest to up to 50 percent of adult does unless you want your herd numbers to grow. The objective is to maintain herd numbers high enough to provide a quality hunting experience without destroying all the habitat.
With an explosion of coyotes and other deer predators, it makes it doubly important to monitor fawn recruitment rates on the property you hunt. An influx of coyotes can cut fawn recruitment in half (or worse) almost overnight. Your state agency will probably have no idea, or at least no data, on the coyote predation and be issuing too many doe tags. The last thing you want to do is be filling doe tags just because you happen to have them. Keeping track of fawn recruitment is the best way we know of keeping an eye on the population dynamics of the deer herd you hunt. It will help you establish sound doe harvest guidelines and, be a better deer manager/hunter and give you something useful to do right up to hunting season.