Assessing the age of white-tailed deer

I love white-tailed deer. I love talking about whitetails, looking at photos of them, and will find any excuse to discuss them. A frequent subject of these conversations is deer age — always an interesting topic, especially with large and mature whitetails. Having a good idea of a deer’s age may help some hunters decide which deer to harvest, and which ones to pass on.

Here’s what to consider and what to look for when aging your next whitetail.

Healthy white-tailed deer herd

Herd management is key. For those looking to harvest mature whitetails, being able to accurately identify a deer’s age is important. To have the opportunity to harvest mature whitetails, they must be allowed to grow. This allows for healthy, balanced age structures in a deer population. Quality deer management, and what a hunter should harvest is not the focus here. I am not one to advocate that hunters shouldn’t shoot young bucks. I’m at a stage of my life where I like big whitetails and am content watching smaller deer walk away. I wasn’t always this way, and I may not continue to be. Depending on the scenario, I may be more content with a spike in a unique situation than a large, mature whitetail in another. I believe in the “shoot what makes you happy” motto. Be proud of your harvest, and the time and effort put into it.

Antlers not accurate

Antler size is often discussed when aging deer. It can help distinguish between mature and immature whitetails, but is simply not the most accurate measuring tool.

For example, a well-developed two-year-old deer could be mistaken for a three or four-year- old. On the flip side, a smaller-antlered four or five-year-old deer could be mistaken for a two or three-year-old. It should also be noted that a one or one-and-a-half-year-old deer is essentially the same age, since one referenced in the fall would have been born the previous spring.

Joe Dampier, a whitetail bowhunter, and friend who also targets mature deer, urges caution when using antlers to gauge age. He never relies on antlers alone, especially once a deer reaches about three-and-a-half years of age.

“Mass is one of the biggest factors. A deer could be pretty tall and wide, but very generally speaking if it doesn’t have any mass, it is probably not a mature deer,” he said.

How a deer’s mass is distributed is another consideration, Dampier added. “Older, mature deer will carry mass down the main beams, and the main beams will start to look beefy.”

Body features can be helpful when aging deer, but the process is far from an exact science. It can take years of practice to become confident in your estimations. Here are some general guidelines to look at when trying to take your best guess.

1.5-year-old

It will have a thin, lean-looking body and neck. It will look young, with a back that slopes down from rear end to front. Its head and nose will be long, thin, and lean, with features similar to a young doe. Much like a calf moose, its legs will look long and slender compared to a proportionally small body. Its hind end will be relatively lean, with little bulk. Its antlers may have spikes, but could fork into four, six, or even eight points, but won’t likely spread beyond the ears. The back and belly will not sag and will look lean and tight. At this age, antlers are a pretty good indicator.

2.5-year-old

Still very similar to a one-and-a-half, with that sloping back, though perhaps slightly less pronounced. The rear end will have a little more bulk, but it will still be a relatively lean, slender looking animal. It may resemble a large doe. With a slender, thin face, and nose. Its antlers will likely start to branch out from a yearling and spread out maybe to the width of and not beyond the ears, with little mass. There still isn’t likely to be any sag in the belly and back, and it will look lean, with particularly long legs.

3.5-year-old

At three-and-a-half, a buck’s back will start to look even and flat from front to back, with perhaps the slightest slope from back to front. It will look like they carry their weight more evenly and have more even bulk in their front and rear end. The thin, lean, almost awkward look from year one and two are essentially gone, and they will look more filled out. Antlers will often start to look impressive, with some decent tine length and mass, and likely spread well outside the ears, although this is a generalization that can vary greatly. Legs will start to look like they fit the body more and look less long and gangly.

4.5-year-old

This is where many deer can start to look really impressive, often carrying significant bulk and impressive antler growth. The back will be straight and flat across, with a more solid-looking front end.

The belly may start to have a slight sag. Weight will be evenly distributed, and it will look like the front end, rear end, and legs are all proportional. The head will look solid and filled out, and that long, thin lean nose will be gone. Generally speaking, a deer that reaches this age class will stand out when it comes to body size and composition and antlers.

5.5-year-old

At this age, antlers will in many cases be quite impressive. This large, solid animal may start to show some sagging in the back and belly. Its front end may also start to look a little thicker than the rear. The legs may start to almost look a little too short, and the body thicker. It may not look as perfect as the year prior.

6.5-year-old

At this age, this deer will likely stop you in your tracks. It will be large, and likely have large, heavy antlers. The front end starts to look heavier than the back end, with some sagging in the belly and back. Its legs will now look disproportional to the body, and look almost too short with the large body. The head will be blocky, with a solid head, rounded nose, and thick neck and chest, and will just be generally large.

How giant bucks are made

There is an allure to the challenge of targeting mature deer, but not necessarily those with potential to become giants, Dampier explained.

Not only is it important for hunters to age deer, but to recognize when a deer has the potential to turn into something special.

“You can start to see and understand that a deer may be four-years-old, but likely isn’t going to amount to something. Then you may see an immature deer, at three-years-old, with great tine length, lots of mass, things that show it has big potential,” he said.

“You can’t shoot 160- inch deer if you shoot three-year-olds.”

Watching live deer can also help greatly. In Thunder Bay, we have an area with a very healthy urban deer population. In a situation like this, you can watch them side by side and see the differences between young and old deer. It’s possible to focus on the specific features as you become more able to identify them.

Story time

Some things can still trick you, no matter how good you are at estimating deer age. A friend and I both had several years’ worth of photos of a tall, unique buck that frequents nearby properties. It was an eight-year-old with an impressive set of antlers. My friend’s dad stopped him from shooting it years ago after recognizing its potential.

When I shared photos online with friends, most put the deer in the three-and-a-half to four-and-a-half-year range. But based on our photo records going back to 2018 (when the deer was at least two-and-a-half and likely already three-and-a-half), we knew the deer was likely seven-and-a-half years old in the fall of 2022.

Features can change significantly throughout the season. A mature buck in early October can look very different by early November during the rut, and even more so by early December after the rigours of the rut.

Even for those competent at it, aging deer can be tough to nail down consistently. Trail cameras are great tools. But camera placement and photo angle remain factors that make gauging important features challenging.

What he looks for

Dampier analyzes several features when aging bucks, starting with body size.

“When you see what you think is a good-sized buck, and then you see a six-and-a-half-year-old deer next to them, they just dwarf them. They are bigger in the shoulders. The overall dimensions are just so much bigger. A truly mature whitetail just looks giant all around.”

He also shared some wisdom when it comes to determining mature vs. immature. “If he has that sleek racehorse look, with a tight belly, everything looks taut and impressive, it is likely not a mature deer. Truly mature deer have a bit of belly sag, a bit of dad-bod belly, and they start getting a sway back. They don’t have really tight lines, and no longer have that tight, sleek racehorse look.”

Dampier also pays particular attention to the neck, and the separation or lack thereof between it and the chest.

“When you look at some deer, the neck is clearly separate from the chest. When you can’t discern where neck ends and chest begins, the neck essentially runs right into that chest. That is typically a big, mature deer. Mature bucks also start to develop a big inner muscle on their neck. When looking at a mature deer from the front, the neck below the jaw almost looks squared off, not the nice typical rounded smooth neck.”

With mature deer, there is also some separation between the front legs, where the front legs look tight together on a young buck, he said. Dampier also describes a deer that is in that five-and-half- year-plus range as having a blockier head, and a rounded, Roman nose.

The question of what is mature or not may vary, but Dampier considers them mature at age five- and-a-half. “At four-and-a-half, they just rarely have that real mass, and are typically slightly spindlier.

A four-and-a-half-year-old can be awfully hard to pass up, but I think they truly mature once they hit five-and-a-half.”

Dampier’s parting words were simple and clear.

“If it starts to look more like a steer than a deer, they are likely mature.”

Two more ways to age your deer:

Tarsal gland staining: This is another feature to look at, and one that can be rather challenging until you have seen the differences many times. Young bucks will have little tarsal gland staining, and it will get increasingly more noticeable with age.

Teeth tell the tale: One of the most accurate ways to age a deer is by analyzing its teeth/jaw. There are some great resources available online to show you how to remove the jaw, and age a whitetail based on teeth and wear. Over time, this process can help you better learn and estimate age on the hoof.

Originally published in the Fall 2023 issue of Ontario OUT of DOORS