Does your deer herd measure up?

The deer season is over, so now is the time to look at the data

There was a lot of antler measuring going on during the Louisiana Sportsman Show in mid-March.

My hat goes off to Scott Durham, Tony Vidrine, Jonathan Bordelon and Keith LaCaze. For two days we measured more than 110 entries in the Louisiana Sportsman Big Buck Contest.

The racks were measured according to Boone and Crockett, and Pope and Young standards, which means deductions were taken for lack of symmetry.

Hunters do not like deductions, but these two record programs are the standard for judging white-tailed deer in this country.

Measuring antlers is also an excellent way for a club or landowner to determine if the deer program is working.

We scored quite a few bucks that qualified for the Louisiana Recognition Program (minimum score of 130), and there were many bucks that qualified for the Mississippi Magnolia Record Program (minimum score 125).

There was, however, only one typical buck that will qualify for the Boone and Crockett All-Time Record Buck (minimum score 170).

This was the great deer Donald Forbes killed on private land in East Baton Rouge Parish.

“East Baton Rouge Parish,” you say, “is not really known for producing trophy class deer.”

It just goes to show that age, along with good, native Louisiana habitat, will produce trophy deer without the high cost often associated with trophy deer management.

The Forbes’ buck was typical of B&C bucks — the data shows that less than 1 percent of the bucks harvested will qualify for this recognition.

This should indicate that a program designed to grow true record-book deer is not really made for the average landowner or hunting club, which is why I always say manage for what the habitat will produce and be satisfied with that.

Landowners and clubs harvesting adult bucks that regularly score 125-inch-plus or 130-inch-plus deer have a darn good program and are doing something right.

These are bucks that most hunters would mount, and is a desirable goal or objective for your deer-management program.

However, if your adult bucks are scoring 110 or less, it should be obvious that something is wrong — low-quality habitat with poor nutrition and/or too many deer occupying the habitat.

This is where knowing growth and development trends of your deer herd is important. These trends will point out deficiencies in growth and development, and should help identify what problems are causing this lack of body and antler growth.

Every year, landowners and hunters spend a pile of money on their deer-management programs, and the harvest data you collect during a season will determine if the money is being wasted or is actually producing results.

Didn’t collect any harvest data? Well, hopefully you had some fun with your deer hunting and maybe killed a deer or two.

But the only way to really know what is happening with your deer population is to examine harvest data. This means collecting jawbones for aging, weighing deer (not just estimating the weight), checking does for lactation so you have information about production and measuring antlers.

The key to harvest data is knowing the age of the animal. Without it, you might as well not worry about collecting data at all — just hunt and have fun.

Collecting jawbones is a messy job, but it is the foundation for determining deer growth and antler development. The Forbes buck was a mature deer and had the quality that a mature buck should possess.

I killed a 6 ½-year-old 10-point in Bossier Parish this past season. This habitat should be dominate flatwood-hardwoods, with a good oak component, but unfortunately the hardwood habitat has been clear-cut, planted with pines and is intensely managed for pines — meaning herbicides are used to reduce the hardwood growth.

So the habitat is lacking the quality nutrition needed for good growth and antler development. The B&C score of my mature buck was 100 inches.

A 7 1/2-year-old buck that David Reynerson killed on bottomland hardwood habitat with nearby agriculture in Avoyelles Parish was a basic 8-pointer that scored 135 inches.

Deer growth and development is all about having the proper nutrition for an animal to eat every day of the year so it can achieve maximum body and antler growth.

The three basic age groups in a deer population that need to be known in order to establish population growth trends include: fawns (6-month-old deer), yearlings ( 1 ½-year-old deer) and adults ( 2 ½-year-old-plus deer). If you can group your deer harvest into these age groups, you will be able to establish growth trends for your deer herd.

While biologists age deer out into the older age groups, it is really not necessary in order to establish basic growth trends. Now, certainly if you are trying to manage for an older age group of bucks it is worthwhile to know the specific age class for the adult deer and determine what is happening in each age class.

To illustrate my point, assume that 6-month-old male fawns harvested averaged 65 pounds (live weight). You say you don’t shoot male fawns because these are going to be the big bucks in future years? Well, there is no reason at all not to collect a small sample of these bucks and see what is going on in this age class.

With adequate habitat, these 65-pound male fawns should double their weight one year later.

Now, suppose your yearling bucks (1 ½-year-old males) harvested the next season only averaged 110 pounds live weight and not the 130 pounds that was anticipated. You say you do not shoot yearling bucks because you let them go so they can grow? Again, you need to sample from this age group so you know what is actually going on.

The data shows that the 65-pound fawns only gained 45 pounds (a 70-percent increase). A yearling buck that weighs 130 pounds has a much better chance of becoming the desired quality buck than one that weighs 110 pounds.

If the 1 ½-year-old bucks averaged only 100 pounds live weight, I would say you have problems that need to be addressed — either habitat or the deer herd, or both.

Believe me, 100-pound 3-inch spikes living in a dominant pine forest do not become bucks that will score 125 inches as 4 ½-year-old deer.

Suppose when you looked at your data and the lactation rate for adult does (2 ½-year-old-plus deer) was 60 percent. This means that out of 10 adult does harvested only six produced fawns.

This is a low lactation rate, because on good habitat adult does should produce twins. The low lactation rate should send up a red flag and indicate reproduction is not what it is supposed to be.

If these adult does only averaged 105 pounds live weight, poor nutrition or a high deer density might be the problem. Adult does with low body weights do not produce many fawns.

If these does averaged 120 pounds, perhaps there are problems with fawn mortality due to predation. Lactation information is simple data to collect, but it is important if you are really trying to manage your deer herd.

If you harvest enough deer from your property you can use the data to obtain a crude estimate of your total deer population.

For example, a friend of mine has 1,200 acres of excellent deer habitat in Pointe Coupee Parish. He is managing for quality deer, with the harvest emphasis on does and quality adult bucks.

During the 2013 deer season six female fawns were harvested. During the 2014 season, 101 ½-year-old female does were harvested. Add the two together and we know that at least 16 female fawns were born in 2013.

Now, certainly, all the female fawns born in 2013 have not been killed. So, in order to obtain a crude population estimate, let us assume that 70 percent of the female fawns born in 2013 have been killed either from hunting or natural mortality.

Using our old ninth-grade algebra equation of x= female fawns born in 2013, then .70x=16; therefore x=22 female fawns.

Now fawns are pretty much born at a 50/50 rate; therefore the total estimated fawn production, male and female, for 2013 was 44.

Now, keep in mind that this is really a minimum estimate for fawns born in 2013 — more than likely there were more fawns born.

Now that we have an estimate for the fawn population in 2013, we can use it to obtain a crude estimate of the total deer population.

The typical deer herd is generally comprised of one-third fawns, one-third yearlings and one-third adults. Therefore if our estimated fawn population for 2013 was 44, using our algebra equation again means 1/3X (X=deer population)=44, then X=133 deer.

Our estimated deer population of 133 equates to one deer per nine acres, which is a very good deer population.

Our estimated population is in the ball park based on the annual browse survey, which finds high deer browsing on the spring habitat.

The doe harvest on this property, despite what hunters on adjoining property think, is in no way impacting the deer population and helps the herd achieve desired growth and development.

Even if you only harvest a handful of deer, you can still collect harvest data, look at the deer harvest reports on the LDWF website and see how your deer compare to the deer on the various habitat types in the state.

Since the data is broken down by habitat, you can compare apples with apples. If the 2 ½-year-old adult buck you killed only weighed 135 pounds and the average live weight for your habitat type is 165 pounds, then obviously something is wrong, and perhaps you have the ability to do some management work that will improve the growth and development on your landscape.

And now is the time to be doing the habitat work for the 2015 season.

About David Moreland 245 Articles
David Moreland is a retired wildlife biologist with LDWF, having served as the State Deer Biologist for 13 years and as Chief of the Wildlife Division for three years. He and his wife Prudy live in rural East Feliciana Parish.