How to Manage Whitetails on Private Lands: Part 7

This is the final installment of a year-long series on how to develop a whitetail management plan for your land. I began with a discussion on the need for sound goal setting with a focus on the three tenets of white-tailed deer management: population, habitat and people management. Once you have a reasonable goal, the next step is to develop a series of objectives to reach your goal.

Before you can develop objectives, you must learn as much as you can about your property and deer herd; in order to isolate the limiting factors of your property. It all begins with collecting the right information, including the demographics (sex ratio and age structure), reproductive potential of the herd, and potential mortality factors. Next, you will need to identify the various habitat elements present on your land and determine which are restricted or lacking. Then you must deal with the people who will be involved in the implementation of the plan, including hunters, plus the economic and physical limitations to success.

The emphasis has been on collecting data that best serves your initial developmental plan, as well as assessing the success of your program. As a colleague once said, “Without data, everyone’s opinion is as good as everyone else’s!” In this final installment, I will illustrate how useful good data can be in guiding your decision-making. Let’s begin with the population data.

The Metrics of Deer Management

You probably understand by now that I have little faith in methods to estimate the number of deer you have on your property! It’s a moving target at best, and a question that you really do not need to answer. If you “ask” the right questions of your deer herd and habitat, they will be more than happy to provide the answers.

The most critical of these for population management is the demographic structure of your herd. You must reflect on what you have done in the past to compare the current productivity of your deer herd. Is it safe for me to say that the percentage of deer reaching maturity is an indicator of the reproductive success of your deer? At a glance, harvest age structure tells me exactly what is going on and what you have done with your herd.

Buck Demographics

As I noted in Part Three, you can conduct trail camera studies on your property that will reveal the age structure of your buck herd. Yes, it takes a little training and practice to accurately age bucks from the photographs, but we have trained hundreds of landowners to do so successfully!

Remember, you just have to place each buck into one of the following categories: fawn, yearling, immature (2 1/2 to 3 1/2 years), mature (4 1/2 to 5 1/2 years) and over-mature (6 1/2 years+).

Buck:Doe Ratio

In Part Three, I discussed how you can use trail cameras or incidental sightings data to determine the buck:doe ratio. The natural ratio, as far as we can tell, is 1:1.5 to 1:2; and there are few modern deer herds with that good a ratio! We have seen ratios as high as 1:8 in some areas where buck harvest is very heavy and doe harvest very low. I have been criticized by some biologists for reporting such a high ratio, so let me explain how this can happen.

First, buck:doe ratio often is calculated using buck fawns that have not been recruited into the population. Second, in some areas, doe harvest is way below what is needed to increase recruitment. So, when you combine these two facts, it is indeed possible to have sex ratios skewed that much! The goal for this metric should be 1:2, no greater than 1:3.

Doe Demographics

Under normal conditions, the generation time of a deer herd is about 3 1/2 years. Our studies over the last 20 years suggest that the largest percentage of the fawns are produced by does less than 4 1/2 years of age. Where this is not the case, we call a “stagnant” deer herd! The quality metric we then use for age structure of does in the harvest is 50-60 percent in the 3 1/2 years or younger class.

This metric also reflects the correct amount of harvest pressure placed on the does on your property. Proper doe harvest, coupled with nutrition management, increases reproductive success, one of the most critical management metrics!

Recruitment

Remember the estimated fawn crop is not the true measure of the actual growth of your deer herd! Fawn crop is expressed as an estimated number of fawns surviving the first six months or so of their life, expressed as fawns per 100 does (as a percent). You derive this estimate either by recording all the deer you see on your property in fall, as bucks, does and fawns, or by conducting a trail camera census.

Dividing the number of fawns seen or photographed by the number of does produces the percentage estimate. Fawn crop can be quite high, and in some areas we have seen estimated fawn crops as high as 90 percent. However, this is not the metric we need to assess productivity of your herd! True recruitment is the percentage that reach one year of age. Our research suggests you need at least a 40 percent recruitment to have huntable numbers of mature bucks. This should be your minimum metric for rating the productivity of your herd.

Antler Quality

I think it is safe for me to say that every record-book buck once was 18 months of age! So, it is intuitive that having older age class bucks in your herd will result in larger antlers. However, other than age, is there an antler metric for judging your progress in management?

The white-tailed deer “wants” to have 8 points and score around 130 inches Boone & Crockett at maturity; I do not care where you hunt! Our landmark study on antler development in free-ranging bucks revealed that less than 15 percent of yearling bucks will ever break 150 inches in their lifetime! Less than 1 percent will break 160 inches.

Some landowners and managers record the B&C scores of all bucks harvested, then use the average score as a metric for management success. Frankly, I am more concerned with assuring that you do not degrade the herd, than increasing antler size. In many areas, buck harvest has been so heavy for so many years, that most bucks do not reach even the average!

There has been controversy concerning antler restrictions; with some hunters calling this management practice “trophy management.” In reality, larger antlers are just the “side benefit” of antler restrictions, while the real purpose is to increase buck age structure toward a more natural herd.

We tend to use antler measurements that relate to the nutritional plane of our deer, including basal antler circumference, beam length and antler spread. We also calculate a “frame score” for bucks, which essentially expresses the size of the box it takes to hold the antlers! The frame score is calculated by adding the outside spread, average beam length and average tine length.

Habitat Diversity

In Part Five, I discussed the analysis of your property in regard to habitat quality. I noted that our early radio-telemetry studies in the eastern U.S. revealed that deer would “like” to spend most of the year with an 80-acre area. We designate this area the Minimum Management Unit (MMU).

In the area west of IH 35, the MMU may be larger, perhaps around 180 acres; and in the drier climates even larger, as much as 400 acres. Yet, this is seldom realized, since most landscapes do not supply all the life requisites in that size area.

Now, I am fully aware that not everyone owns or controls at least 80 acres, and all land is not square! In management, you have to make do with what you have, yet there always is room for improvement. And you often can supply what surrounding landowners do not provide. The primary habitat elements are foraging habitat, cover, travel corridors, water and sanctuaries.

Your management plan should include a detailed analysis of your property regarding the availability and extent of these elements. My research has taught me that deer need about 30 percent of the MMU as foraging habitat, comprised mostly of browse and herbaceous vegetation within the “deer zone” (4 1/2 feet from ground level).

An additional 10 percent can be devoted to fruit and mast production areas, although they may overlap with foraging habitat. There should be one permanent water source in each MMU, and it can be man-made or natural. Another 20-30 percent should be in cover, but there are different types of cover, including summer thermal, winter thermal, escape and edge.

Escape cover is any area in which a deer can run within 25 yards, stop, and not be seen by the intruder! Edges are very important, especially soft edges where forest or brush gently transitions into an opening. The remainder of each MMU should be developed for cultivated forages (where climate allows), travel corridors (natural or constructed) and sanctuaries.

A sanctuary is any area that allows a deer to bed down or “loaf” without the possibility of being surprised by an intruder. There is no standard sanctuary structure, just so long as it provides the function.

So, what is the metric for evaluating progress in habitat management? Once you have your land analyzed by habitat type, you should develop goals to improve or provide these critical elements. The metric then is how much progress have you made in this process? Habitat improvement often is a long-term proposition, and you must develop many land management skills, as well as acquire equipment, to carry out objectives.

Lastly, I recommend spending a lot of time on your land, just watching your deer! Deer management is a “lifestyle,” and there is joy in making your property a better place for deer and other wildlife! Part of this process is “tweaking” your habitats to improve their utility and use by deer. Again, ask the right questions, and your deer will tell you the right answers!

People Management

The greatest metric for the success of your management program can be found in the amount of time you spend on your land. Do you look forward to being there, or do you dread the work that needs to be done? When asked why he needed my help, one landowner replied: “I want you to help me make this place one where my grandkids want to be!”

Have the people who hunt and recreate on your land learned more about the deer and what it takes to make their lives better? Can most of them guess accurately the age of a deer they see? Do they stay in the woods longer? These are just some of the metrics I use to measure my success, and you will discover they provide all the answers. I consider the land we own as my effort to restore a tiny piece of what once had to be Eden! Have fun, dear friends.

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