Balancing The Deer Herd

As a teenager in Texas in the 1950s, I quickly learned I shouldn’t shoot does. That was a standard no-no back in those days. But as it turned out, it also was bad advice — or at least incomplete.

In that era not long after World War II, deer-management efforts were still being aimed at restoring populations devastated by the overhunting abuses of the 19th century. The need to control deer numbers wasn’t even a significant concern in management when I was a kid. Several generations of hunters had grown aware of the need to let the herd grow.

Yet I also recall that just over a decade later I stood by an East Texas campfire, trying to convince members of a hunting club that they actually needed to start shooting some does. I was representing the timber company that owned the land these guys hunted, and at that meeting I handed out some antlerless permits. I later learned that after I left, the hunters ceremoniously burned them.

Some 10 years later, the East Texas herd crashed from overpopulation. The state then went to a system using “doe days,” making it legal to shoot antlerless deer only on certain dates. As always, that didn’t work well, either.

Today, most East Texas hunters fully accept the need for doe harvest. In fact, most hunters across the whitetail’s range see it as a legitimate management practice. Yet questions about doe removal remain. The most common questions I’m asked include: (1) How many does should we shoot? (2) Which ones should we take out? And (3) When should they be harvested? Let’s address those points.

A Brief History Lesson

In most places, back in the ’70s whitetail herds were growing at an exponential rate. In fact, here in the South, numbers were almost doubling yearly, and it seemed to most professionals there would be no limit to the number of does we could remove. Particularly in the South and Midwest, changing land-use practices favored an explosion of deer foods. There also were few predators or diseases to consider. It was a simple ecosystem to manage.

In this environment we created a short-lived concept of deer harvest based on what’s known as compensatory response. That is, if we harvested more does, the remainder responded by recruiting more fawns into the herd. Improved nutrition allowed for that.

This was a concept hard to sell to the public, but it was valid. Most adult does deliver two fawns, but only a percentage live to reach one year of age. That percentage we call the recruitment rate. On highly productive range, recruitment can be 80-90 percent, ultimately resulting in a runaway herd that eventually depletes its habitat and crashes.

The deer ecosystem isn’t quite that simple today. Aging of forests, clean agriculture, the rise of an impressive array of large predators and disease have complicated management. Hunters now are competing for a resource that is limited and has to be shared with a host of mortality agents.

Setting Your Doe Limit

So the question as to how many deer to harvest has a complicated answer. Ideally, each year you should be able to take the number recruited, minus other mortality factors. If you have a 100-acre property housing 10 deer (a ratio of 1 buck to 3 does (2-3 bucks and 7-8 does) and a doe herd that recruits at only 45 percent, you have to share an annual crop of 3-4 deer. And that’s just the yearlings!

Assuming the best case, we have two bucks and two does coming into the herd as yearlings. Allowing for 1-2 per year mortality, that means there will be 1.8 bucks and 1.8 does reaching the age of 2 1/2. And that’s if everyone refrains from killing any bucks as yearlings! If we shoot the bucks at age 2 1/2 and leave the does, the sex ratio will continue to be skewed toward the female side.

So before giving an answer, I usually ask how many bucks the person is taking off the property. Then I say, “You can shoot a doe for every buck you harvest.” There’s no such thing as a “cookbook” recommendation, but I’ve seen few properties with good deer habitat prove unable to sustain an annual doe harvest of at least 1 per 100 acres.

Identifying Target Does

Doe social groups are made up of mothers, daughters, grandmothers and aunts. One doe rules the group. I refuse to call these “doe groups,” preferring the term “clan.”

My good friend Miles White is a hunter, not a biologist. Yet as he started managing his land, he figured out right away that there’s a need to address the “which does” question. He asked me what happens to the integrity of the clan if one doe is removed. Removing just one probably doesn’t disrupt the clan’s social structure, but shooting several is a different story. So what I try to teach landowners and managers is to harvest no more than one doe per social group annually.

It’s a good idea to avoid removing the matriarch. So don’t just shoot does randomly. Take time to study the group’s behavior and learn which one is the boss. Then pick another one.

Timing The Harvest

Lastly, when should you shoot does? There are two answers: one from a biologist’s perspective, one from a manager’s. The biologist in me says to shoot them as early in the season as possible, to get those mouths off the range before more forage is consumed. The manager in me says to shoot them later, as too much early hunting pressure will change buck behavior and impact overall harvest success.

As a hunter, I’ve learned to decide to take a doe and then go out with the goal of just doing just that. Otherwise, it’s easy to fail. How often have you fully intended to shoot a doe, only to watch one emerge from the forest edge, stop and looks back? You start to second-guess your harvest decision and wonder if there’s a buck behind her. You let her walk out of view . . . and then a fawn steps out. Your opportunity is gone.

To avoid this scenario, set aside a distinct period during which your entire hunting group commits to the plan of harvesting only does. You can decide ahead of time as to the number, based on the herd data you’ve collected.

In Conclusion

While the principles of deer management are easy to grasp, their application is rarely simple to practice. It seemed so in the old days, when there was a deer behind every bush, but in most places times have changed. We now understand that it’s possible to “collapse” a herd by shooting too many does.

To make sound harvest decisions, study your deer on a year-round basis, at least through the use of well-distributed trail cameras. Learn to recognize doe groups and their composition. Plan ahead as to which ones to take, then carry out the plan. Your reward will be a well-managed herd — and some good venison to boot!