By CP Staff
By Olivia LaVecchia
By Chris Parker
By Jesse Marx
By John Baichtal
By Olivia LaVecchia
By Jesse Marx
By Olivia LaVecchia
"We're finding essentially the same things that they found in Wisconsin," notes Lee Frelich, one of Minnesota's leading ecologists and director of the Center for Hardwoods Ecology at the University of Minnesota. "Deer are one of the major threats to biodiversity in Minnesota."
As the deer population swells, Frelich says, it accelerates what he has dubbed "forest decline syndrome"--a phenomenon characterized by the erosion of soils, the failure of certain keystone tree species to successfully regenerate, and, ultimately, the disappearance of certain native plant species. "It's not an issue of deer or no deer," Frelich adds. "It is an issue of having a deer population that is in a healthy balance. In a forested area, maybe that's 5 or 10 deer per square mile, not 20 or 30."
That 5 to 10 deer per square mile is becoming a rarer thing in Minnesota. In some of the hardwood forests of north central Minnesota--areas not unlike the ones in Wisconsin where Waller found evidence of ecological wreckage--densities of more than 30 deer per square mile are not uncommon. In some places, they are higher. Near Park Rapids, for instance, there are now an estimated 43 deer per square mile.
The changes wrought by those deer aren't visible only to academics crawling with clipboards on the forest floor. Increasingly, the impact is becoming apparent to many people who make their living in the woods. Last May, Quentin Legler, a consulting forester, had occasion to visit a recently logged 30-acre plot of land north of Grand Rapids. The owner of the property had replanted the field with spruce trees, a food source that whitetails generally eschew. But after a late spring snowfall eliminated most of the other available forage, the whitetails moved in.
In a matter of days, says Legler, nearly all the seedlings in the field had been destroyed. "Some people thought it couldn't have been deer, that it must have been hares," says Legler. "But I know what deer browse looks like and it was deer."
Mike Hauser, a manager with the state's largest private landowner and wood products business, the Potlatch Corporation, has had similar experiences. Where people like Hauser used to spend most of their time worrying about the effects of various plant blights, they now worry about deer. For years, foresters have employed "bud caps"--protective paper covers that are placed on top of seedlings--to keep the peak of the tree from being eaten. That way, even if deer munch on a young tree, the terminal bud will eventually grow high enough that animals will be unable to reach it and the tree will survive.
But as the deer population has grown, this defense has become less effective. "What we've found is that the deer are actually pulling the bud caps off," Hauser says. At a loss, Potlatch and other forestry companies are struggling to find other solutions, such as the use of special deer repellants. So far, however, no solution--aside from replanting--has become evident. And that is expensive. A single acre of seedlings, Hauser says, typically costs between $200 and $300 to replant.
There are some obvious ironies in the struggles of Potlatch and other timber concerns to combat all this damage done by deer. Logging is one of the chief reasons that Minnesota now has so many deer. The widespread use of herbicides on tree farms effectively eliminates many of the understory plants the deer prefer. And by using fertilizers, some researchers believe, the foresters are actually making the seedlings more palatable to the deer.
Most important, however, is what the loggers have done to the landscape. Just as urban design lends itself to growing populations of pigeons, rats, geese, and crows, our management of forest lands has lent itself to a swelled whitetail herd. By transforming vast amounts of Minnesota forest into a virtual aspen plantation--the main species used for paper products--we have created deer paradise.
The blame for this can be spread around generously. The federal government, for instance, has allowed much of Minnesota's two national forests, the Superior and the Chippewa, to be managed for timber and paper pulp harvest. (Dissident Forest Service employees bleakly refer to the Chippewa as the "Chip-away" National Forest). Much of the state- and county-owned land in Minnesota is managed even more intensely for paper pulp harvest.
For the state's half-million deer hunters, this has made for a bonanza. As Mark Johnson, the director of the Minnesota Deer Hunters Association says, "These are the good old days for deer hunting." Hunter success rates--the percentage of hunters who bag a deer during the season--are as high as they have ever been. In some permit areas, as many as 78 percent of hunters last year came home with venison for the freezer.
Predictably, the big deer population has been a reliable boon for the Department of Natural Resources, which collects about $14 million annually from the sale of deer hunting licenses.
Most researchers are quick to acknowledge that they don't yet have a full grasp on how all these deer are affecting the ecosystem. The unknowns are one reason there has not been a systematic, statewide effort to dramatically reduce the size of the herd. As Don Waller puts it, "in general, the absence of data is used to infer an absence of impact."