Midland, Mich. — Ice anglers aren’t the only ones who should be wishing for a typical, cold Michigan winter. Deer hunters might well have the same hopes.
Cold weather trims survival of larva of the fly that spreads to white-tailed deer epizootic hemorrhagic disease (EHD), an illness that has killed thousands of Michigan deer this year.
Dr. Steve Schmitt, a veterinarian at the DNR’s Wildlife Disease Laboratory, told Michigan Outdoor News that, with two days of October remaining, his lab had tallied 11,164 reports of dead deer likely killed by EHD.
He said that while losses of deer were falling off quickly with the arrival of cooler weather, discovery of dead animals continued.
“Farmers are picking their corn, and hunters are getting out more, including bowhunters, and they’re finding carcasses” of deer that died earlier in the fall, Schmitt said.
While those carcasses didn’t have clinical potential, he said officials still hoped hunters and others would report discoveries so that researchers could gather the strongest set of information to help guide future management decisions.
(EHD reports, accepted through January 1, can be made to local DNR Wildlife Division offices, or online through the DNR’s web site at www.michigan.gov/dnr; click on “Wildlife & Habitat” and then “Report Diseased Wildlife.”)
Newer cases, with fresher carcasses, were also being examined, especially animals from townships and counties where the disease had not yet been documented.
Thirty Michigan counties have produced lab-confirmed cases of EHD, with Manistee County last week joining the list that also includes Allegan, Barry, Branch, Calhoun, Cass, Clare, Clinton, Eaton, Genesee, Gratiot, Hillsdale, Ingham, Ionia, Isabella, Jackson, Kalamazoo, Kent, Lenawee, Mecosta, Montcalm, Muskegon, Newaygo, Osceola, Ottawa, Saginaw, Shiawassee, St. Joseph, Washtenaw, and Wayne.
Heaviest hit have been counties in southern Michigan, largely mirroring drought and near-drought agricultural maps, Schmitt said – and with good reason.
Larva of the midge fly spend the winter burrowed in mud, said Schmitt, and cold Michigan winters usually kill off most of them.
Last winter, as ice anglers remember painfully, was very mild.
Hot summer weather spurs hatching of young, along with increased activity levels of adults and even more potent doses of the virus.
And, “Last summer was our hottest on record,” said Schmitt, calling the one-two punch “a perfect storm” leading to the outbreak.
Deer that were infected this year but survived, and those exposed to the virus that did not develop the disease, likely carry antibodies to it that will protect them next year. “There’s even some immunity benefit passed along from does to their fawns,” he said.
That’s why many southern states with large populations of midges don’t have huge deer losses each year.
And Michigan? “We’ll probably have some outbreaks every year,” Schmitt said, “but probably not on the level we’ve had this year.”
The effect of this year’s outbreak on hunters will depend on their haunts, Schmitt said, because of its spotty nature. “Some hunters won’t notice a thing; in some areas it will be very noticeable.”
Good news? There is no evidence, the DNR said, that humans can contract the EHD virus either from the midge or from handling and eating venison.