The discovery last week of two Minnesota deer infected with chronic wasting disease opened another chapter in the ongoing struggle to keep the state’s whitetail herd free of a malady that has had broad adverse implications for deer and deer hunters in other states, Wisconsin especially.
Minnesota in fact is bracketed this year by states — Wisconsin as well as South Dakota — that have serious problems with their deer herds.
Wisconsin’s is a familiar acronym, CWD, whereas South Dakota’s — EPD, or epizootic hemorrhagic disease — is less well known.
In Minnesota, because two bucks killed this month by hunters in Fillmore County, in southeast Minnesota, were found to carry CWD, the state Department of Natural Resources (DNR) will begin special hunts on or about Jan. 1 to dramatically reduce deer numbers in a yet-to-be-determined disease management zone.
The intent is to minimize the chances CWD can spread in the southeast by minimizing the size of the region’s herd — the assumption being that remaining deer will be healthy, and from those animals a disease-free herd can be rebuilt.
This approach will be criticized by some who argue that CWD infection of deer is inevitable, and that fighting it by wiping out animals in the trophy-rich southeast is a bad idea and a waste of money.
Fair enough. But consider what happened in Wisconsin, where CWD was discovered in 2002 — and where the state’s 9.5 percent infection rate of tested animals last year was the state’s 10th straight annual increase.
Additionally, as Wisconsin outdoors writer Patrick Durkin has reported, even though 2,182 fewer deer were tested by the Wisconsin DNR in 2015 than in 2011, 56 more CWD infections were found last year, 295 vs. 239.
And in Wisconsin’s Iowa County — located about halfway between Madison and the Iowa border — Durkin reported that 48 percent of bucks 4 to 5 years old tested last year were CWD-positive.
Upshot: Culling deer is unsavory. But it’s the best among options to curb CWD.
Drought takes toll
On a recent day, Paul Ehlen of the Twin Cities and I, along with some friends, hiked a section of land known to be good pheasant country, about halfway between Mitchell and Pierre, S.D.
The birds didn’t disappoint. Wherever we followed our trio of Labradors, whether into corn, milo or grass, roosters took wing with abandon, attempting to escape into an endless prairie sky.
Even in a year when South Dakota’s birds are down a bit, the action was good, as might be expected in the nation’s last best place for pheasant hunting.
What wasn’t expected were the dead deer we found: a handful or so in a morning’s time afield.
Some carcasses were half-eaten by coyotes. Others were sprawled emaciated and akimbo in depressions that in more normal precipitation years would have held water.
Not this year, when a nearly summer-long drought prevailed across South Dakota. One friend of mine, in fact, who lives near Kimball, S.D., said rain was absent in his area 70 days straight.
In that parched environment, a tiny midge, or bug, that carries epizootic hemorrhagic disease, or EHD, proliferated — as did the number of deer bitten by the little critters.
As of mid-November, the South Dakota Game, Fish and Parks Department recorded 2,061 deer — primarily whitetails — killed by EHD. The number is believed by many to be a fraction of the total number of South Dakota whitetails felled by EHD.
Commonly, EHD is referred to as blue tongue disease. But the viruses that cause the two afflictions vary slightly.
Deer suffering from EHD can die within one to three days. But some survive longer. Often their heads and necks swell, and they have trouble breathing. Fever takes hold and they become dehydrated — which is why stricken deer frequently die near water.
Usually, entire herds aren’t wiped out. Outbreaks often affect less than a quarter of deer in an area where the transmitting midges exist.
Unlike CWD, which can be spread in an infected deer’s saliva and other fluids, the infection rate of hemorrhagic disease isn’t related to animal density. So culling a herd to prevent its spread isn’t done.
Still, hunting seasons often are curtailed to preserve healthy animals.
“Our department has responded to these losses by removing all leftover antlerless deer licenses in 10 hunting units from the East River deer season and from two hunting units from the West River deer season,” said Chad Switzer of the South Dakota Game, Fish and Parks Department.
The good news from South Dakota (besides the pheasants): With the arrival of cold weather, the midges have disappeared.
Even better: For whatever reason, EHD hasn’t yet plagued Minnesota deer.
So, even with the discovery in Minnesota (again) of CWD, and even though the DNR is planning to cull the southeast’s deer herd, look at it this way:
Things could be worse.