The Missouri Department of Conservation is asking people to report hemorrhagic disease or HD in deer this summer.
HD refers to two related viruses: epizootic hemorrhagic disease and bluetongue, which are spread to deer though the bite of a tiny, native midge.
Jason Isabelle, MDC’s cervid program supervisor, said most deer will die from the illness, but it’s not 100% fatal.
"We do have some mortality from hemorrhagic disease each year in Missouri," he said. "We do get reports on an annual basis. And it seems like about every 10 years or so, roughly, we'll have a more severe outbreak that will impact more deer in the state."
He said, during most years, HD is a relatively small cause of deer deaths. But deaths from the illness increase during drought periods. Midges breed in mudflats, according to Isabelle, "and so, when you have a drought and it dries down the water, like in ponds, it basically exposes those mudflats, it's ideal breeding ground for the gnats." And during drought, when there's not much water, deer spend more time near available water sources, which puts them in close proximity with midges that transmit HD.
Isabelle wants the public to report dead deer near water so they can better understand HD’s impact. Signs of HD in deer include reluctance to move; difficulty breathing; swelling of the head, neck or tongue; and unusual behavior such as appearing dazed or unresponsive.
"We keep track of the number that we're getting in, what parts of the state, what counties," he said. "And then if it's a particularly significant year, we would respond with changes to bag limits for deer season."
He pointed to 2012 when Missouri was under a severe drought, which led to substantial mortality in the deer population. MDC became more restrictive that year with its firearms, antler permits and the lengths of the antlers portion to allow the deer population to recover.
As Missouri experiences heavier spring rains and drier summers, Isabelle said it's possible the state could see more cases of hemorrhagic disease. So far this year, he said, they've had about 20 reports in a number of counties scattered in mostly central and southern Missouri.
"So, with the dry weather continuing into August," he said, "towards the end of August, we could see an uptick in the number of reports this year."
You can report suspected cases of HD to your local MDC regional office.
