buck to doe ratio | Buck Manager

Small Acreage Deer Management: Part 2

Small Acreage Management Continued

Part one of this two part series on small acreage deer management discussed how selective harvest on properties less than 500 acres in size is difficult to control. Most deer in an area have home ranges that encompass neighboring ranches. The best remedy for combating the small acreage dilemma is to create cooperative, working with adjacent ranches to increase the quantity, and ideally quality, of land under a common white-tailed deer management program.

Increasing the reach of a small acreage management program is the first priority of any small landowner, or even large landowner for that matter. I also want to touch on the other important deer herd issues that were asked about in the first part of this series—estrus cycles, spikes, and buck to doe ratio.

Deer Management & Herd Parameters

First, with regard to the estrus cycles of deer, whitetail does cycle every 28 days. Late-born fawns result from does that cycle later than normal, or does bred on their second or third estrus cycle into the breeding season. Although born later than usual, late-born whitetail fawns are not genetically inferior to fawns born earlier in the fawning season.

In addition, research has shown that fawning date is not a factor in the antler production of yearling (1 1/2 year old) white-tailed bucks. Genes are genes and can not be changed, but antler production is influenced by environmental conditions. This circles back to the importance of managing for and maintaining high quality white-tailed deer habitat.

Small Acreage Deer Management

Buck Harvest on Small Tracts?

This brings us to the long-debated discussion about spike bucks. Some hunters believe spike must be harvested. Some are adamant that the protection of spike bucks is a necessity. There is no single, correct answer to this debate. The harvest approach depends on a specific deer population and the goals of the small acreage land manager. The thoughtful harvest of deer is important to be successful at managing deer and their habitat.

I mentioned that environmental conditions influence buck antler quality. This is true for all age classes, but some bucks in each age class will be better or poorer than average. Research has found that some yearling (1 1/2 year old) bucks on poor diets (simulating poor habitat conditions) still developed into 5, 6, 7, and 8-point deer. This is interesting from a research perspective. However, harvesting spikes will not change the genetic composition of a deer herd on a large or small property. Why? Females contribute at least on-half of the genes found in every fawn.

Furthermore, bucks must be allowed to age if the land manager’s goal is to grow and produce mature, quality bucks. That means not shooting bucks when they are young during the deer hunting season. There are situations when the harvest of spikes is warranted, however.

Deer Harvest is Essential

There is a time when shooting spikes is a good idea. It’s not a situation that all properties face. Reducing the overall deer population is important when the deer density of an area is extremely high, even on small acreages. Too few acres per deer leads to low quality habitat, smaller deer, smaller antlers and fewer fawns. Too many deer creates a nutritional stress in deer which leads to more 1 1/2 year old bucks showing up as spikes.

It’s a feedback loop that has to be broken. Too many total deer for the habitat means more (higher percentage) yearling spike bucks. In this situation, the selective harvest of bucks throughout the ag classes is recommended. This means shooting spikes on the yearling end so that those bucks with 5, 6, 7 and 8 points get to pass go. A high deer situation also means the selective harvest of does throughout the ag classes. Deer management is not just shooting bucks!

While we are on the topic, the study found that 95% of spike bucks are yearlings (1 1/2 years old). There is an occasional 2-year old spike out there, but old spikes are very, very rare.

More than Shooting Deer

I understand why managers tend to focus on buck harvest. Love it or hate it, let’s use the commercial deer breeding world as an example. Again, this is just an example. There is not a single deer breeder out there lining up to buy spike-antlered yearling bucks. Why? Because they, like you, know that antler characteristics are highly heritable. The difference is that deer breeding and movement is controlled within a pen.

White-tailed deer management on small acreage is different from management on large acreage. Wild deer move around a lot during the breeding season. There is a good chance that bucks spending a lot of time on your property do not breed the does that spend a lot of time on your property. Furthermore, does can get bred multiple times during an estrus cycle. They can have twin fawns with different sires.

Avoid High Grading Bucks

The standard operating procedure outside of a deer management program is for hunters to shoot the bucks with the most antler points. Under this scenario, these good bucks get harvested early and are not allowed to pass on their much-desired genetics. Under a managed scenario, high-quality young bucks should be protected for later harvest.

Only in high deer density situations should bucks with lower quality antlers be harvested. Again, the objective is not to change the genetics of the deer herd, only to reduce the deer herd and save some young bucks for later harvest. Most small acreage deer management programs will want to protect all young bucks.

Deer Management & Buck:Doe Ratio

I’ve covered t the importance of buck to doe ratio in the past, so review the article for more in-depth information. Buck to doe ratio is very important in determining fawning dates and small acreage managers should shoot for about a 1:2 buck to doe ratio. Larger and/or game-fenced properties can shoot for a more equal buck to doe ratio (1:1), but smaller ranches should carry a few more does than bucks.

In the case of a 1:10 buck to doe ratio, the number of bucks compared to the number of does is not likely not that bad. It’s difficult and rare to have a ratio that skewed. However, do collect deer survey data in late-summer and early-fall. Develop harvest recommendations based on those estimates based on the goals and objectives of the small acreage deer management program. Since it does sound like the land manager has many more does than bucks, it’s high time to trim down the female segment of the deer herd.

Removing excess does (and bucks) will improve fawning dates. The remaining female deer will get bred earlier, during the first estrus cycle. As a result, this will increase fawn survival by providing less competition and more summer food for nursing does. This works perfectly if the property is providing high quality deer habitat. Better fawn survival means more bucks in the future. Better habitat means bigger bucks and a healthy deer herd.

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.

Late Summer: Time for Deer Surveys

Late summer is not just a stress period for wildlife, its also the time of year to survey white-tailed deer! If you regularly perform surveys on your property, you know the importance of conducting annual population estimates. For those of you that do not, surveys allow deer managers to get a snapshot of the local deer population just prior to hunting season. Without this information, it’s difficult to make harvest recommendations that fall in line with your management objectives.

The first piece of data you need going into the fall is a deer density estimate, or how many acres are available for each deer. In central Texas, where I am located, a good rule of thumb is to 8 to 10 acres of good deer habitat per deer. Free-choice supplemental feeding can drop that to about 6 acres per deer, but one thing to keep in mind is that typically as deer density goes up the quality of individual deer goes down.

The best way to estimate deer density is to perform spotlight surveys. The information collected during spotlight surveys not only includes the number of deer spotted during the census, but also the amount of acreage that was actually observed during the survey. For example, if you have a ranch that is 1,000 acres, you can visually see 200 acres during your census, and you count 20 deer, then you have 100 deer on your property. Without good visibility data the spotlight count data will be worthless. Continue reading “Late Summer: Time for Deer Surveys”

Impact of Buck to Doe Ratios on Whitetail Fawning Dates

Past articles on this site have discussed buck to doe ratio more than once, but today we are going to talk about how buck to doe ratios impact subsequent fawning dates and recruitment of fawns into your white-tailed deer herd. Many factors can impact rutting or breeding activity, but most of the breeding takes place over a relatively short time in healthy deer herds.

Timing, of course, depends on latitude, local conditions, and a host of other factors, but year-in and year-out most of the rut takes place more or less over the same time each year in a given area. Though often overlooked, buck to doe ratio should be an important deer management consideration on your ranch.

Buck to doe ratio can impact fawning dates on your ranch

In the previous paragraph, a “healthy” deer herd was mentioned and it was stated “most” of the breeding takes place at the same time, but what exactly does that mean? Well, a healthy deer herd would be one that is at carrying capacity for the habitat, has a buck to doe ratio of no fewer than 1 buck per 3 does, and all animals are in good body condition. With all of these parameters in place, it would be expected that majority of the breeding would happen over the course of a 10-day period, or even less.

Ratios and the Rut

Why? Well as deer have evolved, the timing of deer breeding/rutting as become more constricted. A properly timed rut results in a high fawn survival rate and ultimately in the survival of the species. In some areas at northern latitudes, climate conditions can be extreme — so deer have adapted to a narrow fawning window.

If fawns are born too early, it can still be too cold. If too late, they may not have enough time to build up the needed body mass and energy needed to get through the winter. At southern latitudes, temperature is not as much of a factor, but it still plays a role for fawns born too early or too late.

Sex Ratios and Early Rut, Late Rut

So without getting into all the factors that can impact fawning dates right now, let’s talk about buck to doe ratios and how that effects the fawning season. White-tailed does come into estrus for only a day or two — usually in high numbers as if someone hit a switch. If they are not bred within that time, they will come back into estrus 28 days later. If there are not enough bucks to service all the does in an area, those does will not get bred until about a month later. If they aren’t bred then, it’s another 28 days. This explains what some people refer to as the “late rut.”

At this point you may be asking yourself, “What’s the problem?” Well, it’s true that deer populations with a high number of does per buck still have high breeding success (percent of does bred), but those deer herds don’t necessarily have good recruitment of fawns into the adult population. One reason can simply be because of habitat conditions.

Recommended Buck to Doe Ratio

If it turns out to be a dry spring, fawns that are born just one month later than expected may suffer some serious consequences, specifically regarding the available food sources for a doe to maintain herself, produce milk and raise fawns. If that timing ends up being 2 months later, then that may be well into the summer season and the odds of a doe raising those same fawns is much closer to zero.

In short, manage lands for a proper buck to doe ratio and it will help increase both breeding and fawning success. It’s recommended that there be no more than 3 does for every 1 buck, with the goal being 2 does per buck in most free-ranging deer herds. In the future, we will discuss some of the other factors that impact fawn survival and recruitment. Deer population parameters are closely intertwined, and the buck to doe ratio of your herd is much more than just a number.

Using Game Cameras to Survey White-tailed Deer

Population estimation of white-tailed deer is an important cornerstone for the development of deer management strategies. However, estimating deer populations in heavily forested regions is difficult because of reduced visibility. Traditional survey methods, including spotlight counts and aerial surveys, provide limited results in dense forests. So now what?

The use of game cameras, or trail cameras, can provide photo records of an individual deer, a deer herd, and important parameters such as population estimates, sex ratios, and productivity. In an attempt to estimate a deer herd using game cameras, a census project was carried out in 2004 in the piney woods of east Texas, on a property 1,002-acres in size. A total of 7 cameras were placed out (1 trail camera per 150-acres) from September 2 to September 12.

A total of 158 photographs of deer were taken during that time. Twenty-three buck, 97 doe, and 48 fawn photos were collected/observed. Of the 23 total buck observations, 15 individual bucks were identified. The buck to doe ratio was calculated to be 1 buck:4.2 does (23 bucks:97 does). Since 15 individual buck photos were taken, 15 was multiplied by 4.2 to give a doe population size of 63 animals. Continue reading “Using Game Cameras to Survey White-tailed Deer”