Whitetail's Keen Senses Challenge Hunters, Wolves
By Paul Gingras

Among the most elusive and graceful animals in Michigan, the deer's defensive abilities rival the predatory skills of their chief natural rival, the wolf. Every autumn, the whitetail's stealth and intelligence translates into an exciting challenge for human hunters. (Photograph courtesy of the Department of Natural Resources)

An intrinsic part of life in the cedar swamps and forests of the Eastern Upper Peninsula, the stealthy white-tailed deer is one of the animals most respected and coveted by hunters. Drawing on innate strengths and honed abilities, the whitetail coexists with natural predators, and every autumn, presents an exciting challenge for even the most practiced human hunters.

The whitetail's senses are sharp and its movements meticulous, making it one of the most elusive and graceful animals in the region, said Steve Sjogren, wildlife biologist for the Eastern Unit of the Hiawatha National Forest.

Speaking both as a hunter and a biologist, "It is interesting to try to move into their world, to understand their behavior and movements," he said.

Although its precise range has never been quantified, a deer's sense of smell is far superior to a human's, said Rod Clute, big game specialist for the Department of Natural Resources (DNR).

A important danger-detection tool, a whitetail's sense of smell is closely tied to its inherent curiosity. An odor will cause a deer to look and listen, Mr. Clute said. If danger is detected, the early warning may help a whitetail take flight in time to save its life.

Often, deer can smell humans before we can see them.

"If you have ever watched deer, they almost always walk against the wind. They want to smell what they are getting into," Mr. Sjogren said. Deer are colorblind, but they have great ability to detect movement, and they can hear far better than human beings.

The sheer size of their ears, and their ability to swivel them 180 degrees independently, enables the whitetail to fully monitor the surrounding area, Mr. Clute added.

These superior senses enable them to avoid detection, sometimes leaving people puzzled, Mr. Sjogren said. Deer often avoid detection even when moving in large numbers.

Deer are hyper-vigilant, constantly practicing their skills, and when they detect danger, they may simply walk away, quietly. This cautious behavior is a product of evolution, the result of centuries of living in the predatory/prey relationship, Mr. Sjogren said.

Critical among the whitetail's survival skills is its capacity to memorize the details of its territory.

"Deer are creatures of habit," Mr. Clute said. They have defined home ranges; they know if something is out of place, they know where escape cover is found, and they use it readily.

Despite honed senses and sharp memories, deer can be surprised, and their enemies sometimes manage to get close, leaving a deer to call upon its last line of defense - to leap, bound, and outrun nearly anything in the forest.

Ahealthy deer can easily outrun a human, Mr. Sjogren said. They can also outrun wolves, which are slower sprinters. But whitetails are not designed to run long distances, nor do they need to. By bounding and sprinting, they can stay out of a predator's range.

Human beings are the whitetail's chief enemy, according to statistics provided by Michigan United Conservation Clubs (MUCC). Of the number that die in a year, the Forest Service estimates 47% are killed by hunters; 41% do not survive winter conditions; cars hit and kill 7%, and wolves take 5%.

Many people are unnecessarily concerned about the impact wolves have on deer herds, Mr. Sjogren said. The impact is small, yet beneficial, since the canines cull out the weak, small, and sick, the same deer that are unlikely to survive winter.

"Wolves and deer have lived in the same habitats for thousands of years," he said. "I think it is a healthy relationship."

For many people, deer hunting remains a tradition that will continue in the E.U.P. as long as suitable deer habitat remains.

Some consider the maintenance of deer habitat a pressing issue, Mr. Sjogren said.

In lower Michigan, deer thrive on the fringes of farmlands, and more live through the milder winters, so foresters do little to maintain winter deer habitat, Mr. Sjogren said. In the Eastern Upper Peninsula, however, deer survival during winter is closely tied to cedar forests, and the E.U.P.'s cedar forests are aging, and becoming heavily browsed, making them less and less suitable for deer survival.

Owing to harsh winter weather and heavy snow, E.U.P. deer create "deer yards," a northern survival strategy in which whitetails congregate in cedar swamps, where they can keep relatively warm in what biologists term "thermal cover."

In the Upper Peninsula, "If you do not have quality deer yards, you will not have many deer," Mr. Sjogren said. "To me, that is the bottom line."

Passing through a deer yard, compared to the forest around it, is like the difference between wading through knee-high snowdrifts and walking along a shoveled sidewalk.

Deer yards average two to three deer per acre, although they congregate at feeding and watering areas.

Cedar creates thermal protection, and cedar buds and branches are an important food source, but many of the E.U.P.'s cedar trees are between 150 and 200 years old, and whitetails have browsed the lower branches, leaving them little forage in long-standing deer yards.

This has led the Forest Service to experiment with growing new cedar forests, a process made difficult by the deer's voracious appetite for cedar shoots.

Sprouting cedar is like candy to the whitetail, Mr. Sjogren said, so it is almost impossible to grow a new cedar forest.

To generate new cedar stands, the Forest Service is experimenting with cutting 50-foot-wide swaths through old cedar forests. The idea is for young cedars to "seed in," Mr. Sjogren said. The method has not proven effective, because the deer over-browse and kill the trees before they mature.

In the Western Unit of the Hiawatha, the Forest Service is experimenting with "exclosures," large, fenced-in areas to keep deer out while trees mature. Deer can jump high, so the fences must be tall, and fallen trees easily damage the fences. Building and maintaining the fences is costly, so the exclosure method is also having a limited effect.

"We have not solved the problem yet," Mr. Sjogren said, but "eventually, I think we will figure out how to re-grow cedar."

In the meantime, the Forest Service is creating forage for the whitetail and other species through timber harvests, which open up areas that later fill in with young aspen trees, another favorite food. These temporary clearings are scattered throughout the Hiawatha. In the 1970s and 1980s, a common practice was to clear forested areas, sow agricultural crops, and keep the clearings open. This created food for deer, but it was a costly practice and did not create new aspen forage or new areas for them to winter, so the Forest Service has shifted its emphasis to creating temporary clearings that provide deer forage.

An estimated 91,000 deer live in the E.U.P. this year, taking into account all areas from Munising south, and west through Drummond Island, said Sherry MacKinnon, wildlife ecologist for the Department of Natural Resources in Newberry.

How well the deer do depends on the winter weather.

After two mild winters, deer are prevalent, and this year's hunters should not be disappointed, she said. If there is an exceptionally hard winter, the increased numbers of deer will pack more tightly into the deer yards, and the population may see a high mortality rate. If not, they will push the fringes of the deer yards and forage farther away.