While November’s firearms deer season is typically the busiest time of year for Schuyler and Scotland County Conservation Agent Shannon Smith, the Missouri Conservation representative has got this year off to an early start thanks to some pesky bugs.
Northeast Missouri is being hit hard by the Hemorrhagic disease, caused in white-tail deer by biting midge flies.
“I definitely have been receiving a high volume of calls recently from people in both Scotland and Schuyler counties reporting dead deer,” said Smith. “Particularly in Scotland County.”
The MDC agent was quick to point out that the disease annually takes its toll on the deer herd, but added this year seems noticeably worse than normal.
“We definitely are getting hit pretty hard here in northeast Missouri,” he stated. “I would say it is similar to 2012, when the outbreak was pretty significant.”
Smith estimated that he has had more than 100 dead deer reported, which he added likely meant significantly higher mortality rates as many dead deer go unfound or unreported.
According to the University of Missouri Extension HD is transmitted by biting midges of the genus Culicoides, with outbreaks generally occurring from August to October, when the bugs are most abundant.
Exports note that disease is an annual occurrence that often goes unnoticed because deer carcasses quickly decompose in warmer temperatures or are consumed by scavengers.
The disease typically is fatal with 72 hours, with deer showing symptoms that include fever; excessive salivation and swollen neck, tongue or eyelids. Infected deer often are sluggish in appearance, and often will be found dead near water sources, related to efforts to relieve the fever.
Extension experts noted that in Missouri most deer that contract HD die quickly because they don’t have antibodies to fight the disease like deer in the southeast United States.
MDC experts agree with the extension representatives that humans are not at risk by handling or eating venison from an HD infected deer. The disease is not contagious from deer to deer, but can impact larger herds of deer that are congregated in areas where the midge flies are prevalent.
Smith recommends that landowners remove the dead deer from ponds or waterways, but added they aren’t really going to hurt anything if they are simply left to decompose in nature.
He added that the recent outbreak likely will have some impact on the overall deer population which might be seen as a negative for hunters.
“Generally I tend to view this as Mother Nature doing her thing to bring the population numbers more into balance,” said Smith. “It absolutely will have an impact on the number of deer hunters will be seeing. However what may be a negative on that front likely will be seen as a positive for some farmers, whose crops may have been taking a hit from higher deer populations.”
Smith said each year he receives reports of deer killed by HD, but this has been the most significant since 2012.
A published paper by scientists Gary Baygents and Majid Bani-Yaghoub in BMC Ecology in September 2018 based on data provided by MDC reported the 2012 outbreak accounted for mortality rates of 6.9 per thousand. The paper also seems to have successfully predicted the next outbreak between 2018-2020 based on a date-driven pattern of outbreaks every six to eight years.
Smith noted that the midge fly larvae are often attributed to muddy conditions and or stagnant water. He noted after a fairly wet June, conditions dried out in July, which may have contributed to conditions for higher fly numbers.
“Farmers may not want to hear this because of some of the late planting, but probably the best thing right now for the deer would be an early frost to kill off a bunch of the midge flies,” he said.