Last fall, several local news outlets reported that Michigan was seeing the state’s worst outbreak of EHD (epizootic hemorrhagic disease) since 2012. EHD is carried by a biting fly called a midge. These flies hang out in exposed mud, usually in the summer, and prey on deer over a six-week period. The frost is what finally kills the midge for the year. According to the Michigan DNR, about seven days after a deer is bitten, it develops signs of the EHD illness—loss of appetite, progressive weakness, excessive saliva, rapid pulse, and fever, until the deer becomes unconscious and dies.  

Michigan State University modeled with West Virginia to study the midge since EHD has been common in the southern US for years. Their research determined three factors that affect midge. When all three occur, the result is a greater outbreak of midge.  

The three factors influencing a midge outbreak are:

1. A warm, early spring—which 2024 had.

2. A wet July—2024 had.

3. A hot, dry fall—and yes, 2024 had. August and September were dry.

Since 2024 played out with all three conditions met, just how bad was the EHD impact for 2024?  

Chad Fedewa, acting deer specialist for the DNR Wildlife Division of Michigan, called the impact of this year’s midge “fairly substantial” in 15 southwest counties, but said 2012 was considerably worse. Fedewa collects EHD data from the DNR’s online reporting system, “Eyes in the Field.” The DNR relies solely on the numbers submitted by hunters, hikers, and other trail seekers for their data. The total number of cases submitted is a rough estimate in that not all deer that die of EHD get reported.

Effects on Ottawa County

Zeroing in on Ottawa County, Fedewa said there were 309 deer reported that were killed by EHD in 2024. Of the 309 deaths, 161 of those were reported in Crockery Township. The other hard-hit areas were in Allendale and Nunica along the Grand River—where the mud is. Occurrences were scattered, as is typical. However, countywide the impact was minimal.

The 2024 deer harvest in Ottawa was 2600. Last year the harvest was 3500. Even though not all of the EHD deaths get reported, the number of deer killed by EHD is still less than half of the deer harvested by hunters. “It’s compensatory, not additive,” Fedewa said, which he explained means the deer killed by EHD would have otherwise died during hunting season.  

The number of EHD deaths in 2024 hold no long-term concerns for the DNR. According to Fedewa, it usually takes three to five years for the deer numbers to return to normal in locations that see a higher death toll, like Crockery Township, Allendale, and Nunica. Hunters in those areas most likely will notice the drop in herd size.

Effects on Michigan

Across the state, EHD had the biggest impact on the 15 southwestern counties. There were occurrences reported in other places in Michigan, but the heaviest losses were from St. Joseph County up to Kent County. A total of 4500 total EHD-related deer deaths were reported.

Fedewa shared that to date, harvest has been down. Kent is down 23%, Ottawa down 13%, St. Joseph down 44%, and Cass down 39%. One of the factors contributing to the decrease could be the midge.

Comparing the numbers, 2012—which was the worst death toll of recent years—was far more severe. 30 counties were impacted and over 15,000 deer were lost in 2012, compared to 15 counties affected and 4500 deer lost in 2024.  

The verdict

Though 2024 saw a decrease in our herds, it was not the devastation local reports hyped it could be. Even so, those who typically hunt in Ottawa County along the Grand River, might want to scout out alternate places to hunt for the next few years.