Harvest Management | Deer Hunting & Management

Factors that Influence Deer Harvest Rates

When it comes to white-tailed deer management—at any scale—the most important factors are deer density and buck to doe ratio. These two numbers are usually indicative of habitat condition and the reproductive potential of the deer herd. Most hunters continue to talk about buck harvest criteria, and although important, they fail to have a good handle on the deer density and buck to doe ratio in their hunting area! In addition, many landowners overlook habitat conditions and factors that limit fawn production and survival.

White-tailed deer harvest rates are important because they determine not only the number of animals you will shoot this year, but more importantly the number of deer that will survive into next year. This is especially important for the doe population because these animals, depending on deer density and sex ratio, can increase the total deer population prior to the next hunting season by 50% or more. This article discusses population and environmental factors that influence white-tailed deer harvest rates on an annual basis.

Harvest rates can vary annually by habitat quantity, habitat quality, fawn production, and white-tailed deer management objectives. Hunters and landowners looking to maintain healthy age structure in bucks should never harvest over 20% of the buck herd. This holds true whether the buck to doe ratio is 1:10 or 1:1. Of course, if the deer density in the area is held constant, many more bucks can be harvested when there is 1 buck for every 1 doe compared to when there is 1 buck for every 10 does. Many hunters fail to realize that from a population standpoint the types of the bucks being shot is less important as the total number of bucks being removed from the herd. In short, limit buck harvest to less than 20% of the buck population.

Doe harvest management is more important in determining the overall dynamics of a white-tailed deer population in a given area. The doe population determines if a deer population declines, remains stable, or grows. However, the doe population is dependent on, as mentioned prior, habitat quantity, habitat quality, fawn production, and management objectives. Because the doe population in an area depends on these annual factors, so does the annual harvest rates.

Habitat Quantity

This is a measure of the total amount of deer habitat available. Does your property have 100 acres of deer habitat or 1,000 acres of deer habitat? Obviously, more deer habitat correlates with a larger population size. Hunters on 100 acres of habitat can not expect to harvest as many deer as hunters on 1,000 acres of habitat, assuming the deer density in that habitat is the same. If both ranches have the same harvest strategy in place, then the 1,000 acres of habitat can harvest 10 times the number of animals. It’s not because those hunters are greedy, it is just that the total deer harvest for a property should be related to available deer habitat, not just property size. In this example, both ranches could have been 1,000 acres in size. We only discussed available deer habitat on those properties. Property size will not effect the harvest rate, only the total number of animals harvested (because of available habitat).

Habitat Quality

Habitat quality is measured by an area’s ability to provide food, cover, water, and space for white-tailed deer. Deer found on high quality habitat have higher reproductive rates than deer found on low quality habitat. Here is an example of how habitat quality impacts harvest rate: Let’s say that there are two ranches 1,000 acres in size. One provides high quality habitat and the other provides low quality habitat. If we assume that the deer density is the same, then fawn production on the high quality habitat will be higher because there is more food per animal. This high quality habitat means more food per doe, a higher reproductive rate, a higher fawn survival rate, and more bucks and does available for harvest each year. In short, properties with high quality habitat must harvest does at a higher rate to keep the deer population stable.

In Summary

Without a doubt, both habitat quantity and quality impact the annual harvest rates of a deer population. Property size does not impact harvest rate, but smaller properties will harvest fewer animals than larger properties based simply on habitat quantity and differences in the sizes of the deer populations. Habitat quality can vary by property depending on habitat management practices (or lack thereof) and deer found on high quality habitat have higher reproductive success. Because of this habitat effect, properties providing high quality habitat must harvest does at higher rates than properties providing low quality deer habitat. Next week, I will discuss how fawn survival, density, and buck to doe ratio also impact white-tailed deer harvest rates.

Doe Harvest with Caution?

Not all that many years ago it was considered unsportsman-like to shoot a doe deer. Since then, however, wildlife biologists and hunters have realized that proper doe harvest is an important part of white-tailed deer management, although I suspect there is a small percentage of landowners that still do not allow doe to be harvested on their properties. After all, a landowner has the ability to be more conservative than the law and choose not to harvest antlerless deer, even if hunting regulations permit it.

But is a no doe harvest really justified? Maybe, but then maybe not—particarly if the only reason holding someone back is the “old school” philosophy of not shooting female deer. It is true that the shooting of does may not be justified in some areas. Not every deer whitetail population can sustain regular doe harvest. Some deer herds may allow periodic doe harvest, such as every other year or every third year, for example, while others need regular (annual) doe harvest to thrive. So why does the harvest of whitetail doe vary by area? Continue reading “Doe Harvest with Caution?”

Cold Weather, Overpopulation Leads to Deer Die-Off

Every hunter wants to harvest a trophy buck, but when it comes to white-tailed deer hunting the reality falls somewhere between shooting a big buck versus deer overpopulation. On one hand, you have hunters that really just want to harvest a single deer, preferably a big, mature buck. Then on the other hand, you have deer numbers that need to be controlled. This will probably not come as a surprise to you, but the average deer hunter only wants to harvest one deer, or more precisely, one buck. While most hunters love seeing numerous deer while out in the field, an important part of deer management is population management.

The reason I bring this up is because just this last week ranches near Kerrville, on the western edge of the Texas Hill Country, were finding dead deer after several days of cold and wet weather. The cause of these deaths — malnutrition. And before assuming that these deer were confined within a high fence that maintained too many animals, I’ll let you know that they were not. In fact, most of the animals found dead were free-ranging white-tailed and axis deer, but they were all starving. Basically, the deer population of the area has exceeded the carrying capacity of the winter range. They were all competing for limited winter forage, and the weakest died.

Reports indicate that the found deer were in poor physical condition, hip bones exposed, backbones showing, and no internal fat. The rumens of most of the dead whitetails were packed with cedar, some dead oak leaves, and even yucca leaves. Axis deer rumens were packed primarily with dry grasses. The cedars (ashe juniper) in the vicinity of the dead animals were severely browsed. Obviously, the cause of death was malnutrition caused by overpopulation that was exacerbated by the cold, wet conditions that persisted over several days.

Axis deer are more susceptible to cold, wet weather than white-tailed deer because they are an exotic subtropical species, but the end result of malnutrition is realized when mixed with winter weather. Deer in less than optimal condition are always more susceptible to disease and death. Additionally, parasite loads can only make an individual animal’s situation worse. So how can winter die-offs be avoided?

First, the deer population must be kept in check with the habitat. Sure, you may only want to harvest one buck, but realize that the health of each individual deer depends on the availability of food. Supplemental feeding can help, but only if it’s at an adequate level and of the proper type to support the deer population. Each deer impacts every other deer because of the competition for limited resources, but this contest can be greatly reduced if free-choice supplemental food is provided 24-7, year-round. When animals are found dead, remember that the weakest die first.

When monitoring a deer population, many factors can indicate potential deer management problems. Individual body weights, fawn survival (as an indicator of doe and habitat health), and habitat use can all be used to gauge herd health. With that said, pay close attention to the health of deer harvested early in the season. Underweight deer (for their age) are good indicators of a potential problem. In addition, if deer are eating undesirable species, such as cedar, they and the habitat are in very poor condition.

Shooting Does With Fawns

Last week I wrote an article discussing harvesting white-tailed deer early in the season, which I strongly recommend. The article discussed why it is important to remove deer before winter, especially does, and the benefits of having a deer herd at carrying capacity. Well, one reader posed a question that many of you may be interested in:

“What about nursing fawns early in the season? Will taking lactating does hinder growth and development in these young deer?”

Yes and no. To begin, whitetail fawns are usually weaned and become functioning ruminants at eight weeks of age. Most fawns at southern latitudes are born in late May and June, meaning the majority of fawns are weaned by the end of August. And this makes sense from a biological perspective, because as late-summer food sources deplete the doe can then rely on the fawn to nourish itself. This covers the majority of whitetail fawns that hunters will encounter in the field during the fall hunting season. Continue reading “Shooting Does With Fawns”

Harvest Does Early In The Season

Deer hunting season takes place in the fall for one primary reason — to remove excess animals from the landscape prior to winter. When it comes to the deer carrying capacity, winter is THE limiting factor. As a result, proper harvest is essential for the deer herd found on your property, their habitat, and your overall deer management program. With the the onset of winter just around the corner, do not forget to harvest deer, especially does, as early as possible.

I mention this now because as the end of the year approaches, the time that many hunters have to head to the field decreases. The Christmas and New Year’s holidays can take away from your days in the field. It’s hard to harvest deer and reach harvest quotas if hunters can not make it out to the ranch.

With winter officially kicking off on December 21, time is running out to get the deer population on your property down to its winter carrying capacity. If you are not sure what the proper deer carrying capacity for your ranch is, then you first need to contact a wildlife biologist in your area. Carrying capacity refers to the number of deer that a property can over-winter.

Proper Doe Harvest - Remove Does Early In The Season

It varies by ecological region, habitat type, and ranch, but it is the first piece of information you need to properly manage any deer herd. If the proper density for a ranch is 1 deer for every 10 acres, then a 1,000 acre ranch can over-winter 100 white-tailed deer. Excess animals, if they exists, must be removed annually to ensure the health of the remaining deer.

With much of the deer season already gone, why should you always aim to harvest deer as early as possible in the season? Below I have listed three good reasons why early doe harvest is important for your deer management program.

Food — This is the primary reason you need to harvest deer early. Natural food sources will decrease throughout winter. If deer surveys estimate that 20 animals need to be removed from the ranch, why let those animals consume limited food resources for an additional month or two prior to harvesting them? Removing them early leaves the natural foods those “dead deer walking” would have consumed for the remaining animals, which keeps your deer herd healthy and strong. If a supplemental feeding program is in place, the same concept applies and you save money.

Buck to Doe Ratio — Bucks will continue to rut and breed does until all does are covered. If a large number of does must be removed, it is best to remove them early. If most of the does are bred early in the season, then bucks can save valuable energy and body mass. In addition, whitetail bucks become more visible because there are fewer does available in the woods. Maintain your buck to doe ratio and the overall health of your herd.

Fawning Dates — As mentioned above, harvesting excess does early in the season allows bucks to cover the remaining does much quicker. Fewer does per buck results in more does being bred on their first cycle. This, in turn, means more fawns are born earlier in the year. These early-born fawns will be larger before the other stress period for white-tailed deer sets in, summer. Early-born fawns means more food for lactating does, resulting in increased fawn production.