spikes | Buck Manager

Buck Management: What’s Up with Missing Brow Tines?

The hunting season has just ended for the majority of white-tailed deer hunters. Now, it’s time to reflect, look back over the past season while it’s all fresh in your mind. If you had the opportunity to spend many days in the field hunting, then you should have a good picture of the overall deer herd using the property you hunt.

Better yet, if you recorded deer observations while hunting, then you have the hard data to support what is happening under your property’s current deer management program. These field observations, in addition to game camera photos, will allow a deer manager to track individual bucks from one year to the next. I strongly recommend keeping both photo and stand observations since some bucks always seem to avoid getting caught on camera.

Are missing brow tines caused by genetics?

Missing Brow Tines

With regards to antlered deer, one issue that always seems to arise is the lack of brow tines (G1) on some whitetail bucks. Hunters have often questioned why some middle-aged and mature bucks simply lack brow tines. Is something going on in the deer herd?

Well, yes. Antler characteristics are genetically linked and highly heritable This means a young buck will likely look a whole lot like his daddy. To back up this claim, I will cite some long-term data collected from Kerr Wildlife Management Area (WMA), located in Texas.

From 1974 to 1997, the research facility at the Kerr WMA was involved in a number of studies designed to determine the role of nutrition and genetics in white-tailed deer antler development. During each of various studies that took place over that time, researchers recorded antler information for individual whitetail bucks throughout a 23 year period.

Deer Hunting and Management

Brow Tines on a Buck?

This wealth of antler data allowed wildlife biologists to back-test 217 whitetail bucks from yearlings (1 1/2) to 3 1/2 years of age and 168 bucks until they were 4 1/2 years old. That’s a lot of deer, and from what I can find, represents one of the largest sets of antler data available. So what did they find?

In short, data from 385 bucks found that 90 percent of the bucks without brow tines at 3 1/2 and 4 1/2 years of age were spikes at 1 1/2 years old! All bucks without brow tines at 1 1/2 years old lacked brow tines at 4 1/2 years old. On the other hand, all bucks with 5 or more points as yearlings had both brow tines at maturity. Bucks that had both brow tines as yearlings had both brow tines at 3 1/2 and 4 1/2 years of age.

Missing Brow Tines Starts with Spike Bucks

Incredible Antler Data

The numbers above speak for themselves. In addition, deer researchers know that antler characteristics in white-tailed deer are highly heritable, so the probability of passing on genes for specific antler characteristics (larger or smaller antlers) is a given. The future of the deer herd on a property depends a good amount on the quality of the bucks doing the breeding.

To sum up, a whitetail buck that has spikes as his first set of antlers has a 90 percent chance of developing into a buck with missing brow tines later in life. A buck that has 5 or more points as his first set of antlers is much more likely to have brow tines later in life, at least according to this data set out of Texas.

Deer Management Implications

How does knowing this information affect you and the deer you manage moving forward? It likely depends on the goals you have for the deer that use your property. If one of the goals is to harvest the maximum number of mature bucks on the property annually then you want to allow all bucks to reach maturity.

However, if you are looking to improve buck antler quality, then at least one of the factors you should consider is the quality of the young bucks on your land. Antlers are the result of genetics, but they are also influenced by the environment. Nutrition plays a role in how genes are expressed, how a buck looks.

This phenomenon can be seen is deer herds with suboptimal nutrition as spike bucks tend to comprise a higher percentage of the young bucks, those 1 1/2 years of age with their very first set of hardened antlers. In these types of situations, increasing the available food by reducing the size of the total deer herd or the addition of supplemental foods/forages may be an appropriate step to increase overall deer health, buck quality.

If a property provides ample food and a manager is seeing a high percentage of 1 1/2 year old bucks without brow tines on the property, then you now know it’s all in the genes. The only way to improve antler quality and reverse missing brow tines in older bucks is to put pressure on spikes and bucks without brow tines, regardless of age.

Deer Management for Brow Tines, Better Antlers

In this situation, deer management practices should also include rolling over the doe herd to reduce the number of old does sired by bucks lacking brow tines. This is not a management strategy that plays out overnight, but a practice that must be integrated into the long-term management of a deer herd using a property.

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.

Impact of Pre-Rut Buck Harvest on Genetics

Early season deer hunting can be very effective because white-tailed bucks are more easily patterned prior to the rut. Novice deer managers may think that removing a high quality buck prior to the rut is a bad idea because it limits the buck’s ability to pass on his genes. Yes, harvesting a buck prior to the rut does limit his ability to pass on his genes, but it does not limit the ability of his offspring. When it comes to deer management we must manage the deer herd, not individual animals. If you manage the herd as a whole then good things will happen.

The most important aspect of managing the buck segment of the deer population on your property should be maintaing good quality bucks in each age class. If you are interested in improving antler quality of bucks then inferior bucks in each age class should be removed. Bucks that are deemed inferior (by your standards) in the yearling, 2 1/2, 3 1/2, 4 1/2 year old age classes should be removed each year. By doing this you ensure that only the best quality bucks remain each year, pass on their genes, and once mature are ready for harvest. Continue reading “Impact of Pre-Rut Buck Harvest on Genetics”