What is a Deer Yard?

The deer yard in question was formerly a barnyard, long since abandoned and no longer used by humans.  There is an overgrown pond just to the north, which made it an especially desirable spot for wildlife.  The area was encircled by trees and indigenous undergrowth, and provided a great deal of privacy for the animals.  One side of the yard was sheltered by the old barn, which stood roughly where the back and side walls of the new construction’s three-car garage is to go.
 
   Old deer yard interior in summer 2014 - old barn on left


From the NEC-approved plans, we assumed these walls would help to shelter the deer yard in much the same way the barn had.  There was a beautifully regenerated, grassy area in the centre, encircled and protected by tall conifers and deciduous trees. 

    Old deer yard entrance in winter - in warmer months, this entrance was very leafy and you could
    not see into the enclosure from this distance at all


You had to go right up to the deer yard entrance to see into it; from our property to the south it just looked like forest.  This provided great privacy and protection for wildlife.  In the summer months, you had to look closely to observe the animal activity inside, though we regularly observed animals travelling along the busy wildlife corridors to reach this protected wooded area. 

 
Old deer yard interior - fall 2014
 

Though referred to as a “deer yard”, this naturalized, sheltered space was also home to many other wildlife: we observed many rabbits, red squirrels, wild turkeys, raccoons and the occasional possum or fox.  Toads and fireflies thrived there.  Doves and Northern Flickers nested in its trees during the warmer months.  The wildlife trails – deliberately planted as such, in long rows back in the 1970s – led wildlife up to this yard and to the sheltered, wooded pond beyond, away from busy Governors Road.  Wildlife have been using these well-established corridors for decades.

    Deer foraging in winter 2014 at old deer yard entrance


Here is what a few other sources have to say about deer yards and their essential role providing shelter for wildlife:

Encyclopedia Britannica:

White-tailed deer may live apart from each other in summer but may form big herds in winter on open prairies or in forests. They trample down the snow in an area that is then known as a “deer yard.” Food includes leaves, twigs, fruits, and nuts, as well as lichens and fungi. 

Vermont Fish and Wildlife Department:

Deer have developed a survival mechanism that relies upon the use, access, and availability of winter habitat. These habitat areas are known as deer wintering areas, deer winter habitat or, more commonly, 'deer yards.' Deer winter habitat is defined as areas of mature or maturing softwood cover, with aspects tending towards the south, southeast, southwest, or even westerly and easterly facing slopes.

Deer wintering areas vary in size and provide essential relief to deer from winter conditions. These areas of softwood cover provide protection from deep snow, cold temperatures, and wind. They provide a dense canopy of softwood trees, a favorable slope and aspect (mentioned above), generally moderate elevation, and low levels of human disturbance in winter.  Energy loss by deer inhabiting these sites is minimized, and survival is favored in deer wintering areas. Wintering areas do not change significantly between years and can be used by generations of deer over many decades if appropriate habitat conditions are maintained. Deer annually migrate, often several miles, from fall habitats to wintering areas. Residential, commercial, or industrial development within or adjacent to a deer wintering area decreases the amount of winter habitat available to deer.  Without adequate winter habitat, northern populations of deer would be subject to extreme fluctuations due to heightened levels of winter mortality during moderate and severe winters.  

In addition to benefits for deer, dense softwood stands provide critical winter food supplies for a variety of other wildlife species… wintering birds routinely find shelter from winds in these conifer stands.  Conserving deer wintering areas is essential to maintaining and managing white-tailed deer in Vermont.

New Brunswick Department of Natural Resources:
 Deer Wintering Areas:

As snow accumulates, deer congregate in wintering areas, commonly known as ‘deer yards’. These areas are usually located in mature softwood stands. They provide protection from the blustery winds, intercept snowfall, and minimize the animal’s heat loss.

As winter starts and snow covers the ground, the deer seeks protection in mature conifer (evergreen) cover. Its winter diet will consist of hardwood twigs and cedar browse.  Deer wintering areas are generally on south- or southeast-facing slopes. This offers protection from prevailing winds and maximizes exposure to the sun's radiant energy. Typically, they are stands of spruce and fir with some cedar. Crown closure – or density of tree cover – is usually between 50 and 70 per cent.

The white-tail develops an extensive network of trails through the wintering area. This reduces the energy required to move about and helps it evade predators.  Wintering areas are key to deer survival in New Brunswick.

Northwoods Sporting Journal (a publication from Maine):

With the onslaught of winter - plummeting temperatures, high winds and driving snow - Maine's whitetail deer population is digging in for the duration. To survive, our statewide deer population, estimated to be in excess of 250,000, must find two things: thermal shelter and browse. These are found in places called deer yards, or deer wintering areas. According to Maine's deer biologist Gerry Lavigne, "deer are highly dependent on wintering habitat for survival every year."

Typically, a deer yard will be an area where there is what wildlife biologists call a "high softwood crown closure." The canopies of large softwood trees provide some thermal shelter from deep snow, penetrating cold and bitter wind. Available browse in these deer yards usually consists of litterfall, which comprises leaves, twigs and arboreal lichen.

For deer, winter is a precarious life-and-death struggle. Depending upon winter's severity index, deer mortality can range from 3 percent to as high as 35 percent.  In January and February, there is a slowing of a deer's metabolic rate with less demand for calories. Not only can deer resorb their muscle tissue to provide desperately needed calories, the accumulated fat in their bodies can be burned as body fuel when winter browse is scarce. During the winter yarding period, fragile fawns and older bucks that are worn out from the fall rut are the most vulnerable to winter mortality. Many of Maine's deer yards have been used by wintering whitetails repeatedly for as long as 50 years.

A March 2015 press release from SWAN ISLAND, Maine:

(NEWS CENTER) -- Maine has received almost fifty inches of snow in the past six weeks. Deer have responded by yarding up.

On Swan Island in the Kennebec River, Wildlife Biologist John Pratte tracks the progress of the deer herd and makes recommendations about deer management accordingly. Deer typically like the cover provided by cedars and hemlocks.

A deer yard provides cover," Pratte told NEWS CENTER. It intercepts the snowfall and reduces the depth of snow on the ground for the deer. Typically in a deer yard, there's a lot less snow than you'll have on the ground out in the open or in the hardwood stands.

Pratte points out many interesting aspects of this deer eco-system. The deer have beaten down trails in order to save the energy used to break paths individually. They are browsing on "litter fall" which is needles and other debris that has fallen from the canopy above.

Pratte sees dozens of deer on each visit as the deer wait in their yards before bolting to cover.

As he tours the yard, he notices a porcupine in the tree above and points out how it will knock "litter" to the forest floor creating good browse for the white tails. He points out that porcupines bite twigs off in order to get to the more succulent tips.

"Deer yards provide a thermal buffer," Pratte says. "The temperature can be a little warmer in here and it also blocks the wind." This enables deer to save precious energy over what can be a long winter.

The conditions can vary all over the State of Maine. However, Maine is the northern edge of white tailed deer range and yarding up is crucial to the deer population.

 

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