Biologists: wrong food can do more harm than good
It’s natural for people to feel compassion for deer when they see them struggle in deep snow and below-zero temperatures. Many people think that providing extra food would help deer survive the winter.
But because deer have specialized digestive systems, giving them supplemental food actually causes more harm than good, Washington Department of Fish and Wildlife (WDFW) Okanogan District Wildlife Biologist Scott Fitkin said.
Deer aren’t adapted to hay, apples, corn, or even commercially formulated deer pellets. The wrong food — particularly an abrupt change in diet — can even be deadly, he said. In addition, feeding deer creates other problems, including greater risk of vehicle collisions and disease.
“It’s easy to sound really callous,” Fitkin said. “I’ve dedicated a lot of time in my career to building a healthy deer population, and it’s heartbreaking to watch deer struggling.”
After the first big snowfall in early November, Okanogan County Commissioner Andy Hover called the WDFW regional director to see if the agency was considering a feeding program. “I was concerned right off the bat,” Hover said, given the forecast for a cold, wet winter.
Hover has called four or five times since then, and said constituents have also expressed concerns.
Hover said the director told him they would monitor the situation. But the director also said the agency didn’t have the infrastructure to carry out a widespread feeding program and that it would have to start much earlier, Hover said.
More than three-quarters of the deer that live in the Methow during the winter are mule deer. This winter, despite the deep snowpack, the deer are doing quite well, Fitkin said. In December, the snow was fluffy, and deer moved easily to access their traditional winter range. Biologists monitoring deer via helicopter saw animals at 4,500 feet, he said.
As the snow became denser, it took more energy for deer to get around, and they began to congregate where it was easier to travel, including on roads. Now deer are walking on the snow, although staying at lower elevations. South-facing slopes in the lower Methow Valley have started to melt out, providing easier access to food, Fitkin said.
The deer diet
Deer eat what biologists call “woody browse.” Bitterbrush, their main winter food source, usually pokes above the snow, but deer will also dig in the snow to get to it. In the winter, mule deer also eat small twigs from trees and may nibble on evergreen needles, Fitkin said.
Although people worry about deer in winter, the most difficult time for mule deer is usually during spring green-up, in part because it takes time for the deer’s digestive system to adjust from their coarse winter browse to tender green shoots. In addition, deer are depleted in the spring, having used up fat they stored before the winter, Fitkin said.
Deer have evolved to make these natural transitions in food sources over the course of the year, but they never adapt to some foods.
Although deer pluck apples off trees in the fall, that’s less of a problem because the fruit is part of a varied diet. Too many apples can eat holes in a deer’s stomach.
Unlike cows or elk, deer aren’t grazers. They generally don’t eat grass, and hay is too coarse, although they may consume small amounts of hay when it’s balanced by their regular diet, Fitkin said. Hover said deer eat alfalfa hay on his farm, but avoid grass hay.
A deer’s digestive system relies on specialized bacteria to break down different types of foods, and it takes time to build the bacteria for a new food source. If the switch is too sudden, it can be fatal.
With the wrong food, deer can actually die with full stomachs because they can’t get the proper nutrition. Fitkin said he’s seen that happen in the valley.
“I understand and appreciate the public’s desire to want to do something when they see animals that appear to be struggling,” WDFW North Central Regional Director Brock Hoenes said.
While it might make us feel good, in the end, feeding can cause more harm than good, Hoenes said.
It’s hard to accept, but “starvation of wild animals is part of nature,” the Mule Deer Working Group of the Western Association of Fish & Wildlife Agencies said.
“It’s upsetting,” Hover said. “Deer have had a hard time with all the fires.”
Although most people aren’t wildlife biologists, they see deer struggling and are troubled, Hover said. He said he values a good working relationship with WDFW and wants to trust their expertise.
The Methow is fortunate to have high-quality habitat for mule deer, including better winter range than in many areas throughout the west, Fitkin said. Most deer in the Methow migrate to higher ground in the summer. The best thing we can do for deer is maintain quality habitat, Fitkin said.
Deer have many adaptations to get through the winter. A deer’s coat is thicker and more insulating than it may appear. They also survive by lowering their metabolic rate and restricting movement to conserve energy, WDFW said.
“Even in well-functioning natural ecosystems, however, some animals succumb during winter months. The winter season helps keep wildlife populations more in balance with available habitat,” WDFW said.
Historic feeding program
During the winter of 1996-97 — the harshest in recent memory — snow started in early October. By December, the snow was 5 feet deep and there were reports of dead deer in people’s yards, Fitkin said.
After much deliberation, WDFW launched an emergency feeding program for mule deer. WDFW set up feeding stations in a few accessible areas in the valley and handed out food to people to put out for deer, said Fitkin.
“In retrospect, it was largely a failure — I’m just going to be blunt,” Fitkin said. Although the feeding program may have helped a few adults survive, most fawns died anyway. At a feeding site, a mother deer may actually kick a fawn off the food to get to it herself. Even in an average winter, only half the fawns survive, he said.
Moreover, any gains were wiped out by increased roadkill, and feeding the deer created other problems, some of which became ingrained. In subsequent years, deer continued to gather on the valley floor, rather than migrate to their natural range. That caused more vehicle collisions and crop damage.
With deer gathered closer to residential areas, the likelihood of interactions between predators and people also increased. When deer congregate in large groups, they become more susceptible to disease and parasites, Fitkin said.
During the 1960s, it was common throughout the west to feed deer, Hoenes said. Hover remembers feeding programs in the valley through the 1980s.
Those programs were dropped as wildlife agencies began to understand that not only were they not achieving the anticipated benefits, but were even causing harm, Hoenes said.
Today, WDFW policy allows for feeding deer if circumstances warrant it, such as when a wildfire burns winter range, Hoenes said.
WDFW has been feeding elk in the Yakima area since the agency fenced a large area to reduce conflicts between elk and agriculture, Hoenes said. The fencing cut off elks’ access to their winter range, so WDFW feeds the animals.
Attitudes about and understanding of wildlife have changed since then, Hoenes said, noting that they probably wouldn’t erect that fence today. Elk also have different digestive systems and can adapt to a wider range of foods, he said.
Annual survey: healthy deer
WDFW completed its annual survey of deer in December. In the Methow, mule deer were well distributed across the landscape. Most started the winter with good fat, after a productive summer with high-quality forage in the high country, Fitkin said.
Despite regular surveys, there’s no precise count of the mule deer population in the Methow watershed. Fitkin said his best estimate is between 8,000 and 12,000.
By the end of the winter, deer grow weak and skinny, but the animals — particularly adult does — rebound in the spring. Although this year may be harder than normal, the deer will get through it, Fitkin said.
