Midge bites killing deer in Morris County

September 7, 2011
Jim Stabile | Special to NJ Press Media

A disease that last month killed deer in Somerset, Hunterdon and Mercer counties has hit deer in southern Morris County.

"The phone's been ringing off the hook," said Bill Stansley, a research scientist for the Division of Fish and Wildlife. "Calls have been picking up from police in your area (Morris County) and from so many other callers lately; Hillsborough has been busy calling for weeks."

Deer recently found ailing and dead in Madison, Florham Park, Chatham, Harding, Long Hill and East Hanover are suspected of having been stricken by the Epizootic Hemorrhagic Disease (EHD), which is caused by bites from the culicoides variipennis midge.

Division Deer Project Leader Carole Stanko said Tuesday there had been many "presumptive reports" of EHD in Morris County. A preliminary lab report confirmed EHD in deer from the Hopewell area, where an estimated 50-100 died last month, after dead deer were also found in the Hillsborough, Princeton, East Amwell and Montgomery townships.

Two sick deer were shot for tissue samples and dead deer were found in the woods around the Fairmount Country Club in Chatham Township. Some areas had an odor of dead deer decomposing in the woods.

"The smell of dead deer was everywhere," said Bill Koch, manager of the Great Swamp National Wildlife Refuge. "It was reminiscent of 2007(the area's last outbreak)."

The Division of Fish and Wildlife is awaiting lab reports from organ-tissue samples from more dead deer to be sure they died from EHD, as symptoms have indicated. Deer with EHD salivate, have redness around their eyes and lose fear of humans. Lab samples have to be taken within 24 hours of a deer's death and require the lab to grow the virus for weeks.

Infected deer usually seek and are found dead around water, where they go trying to cool their fever. EHD cannot be transmitted from deer to deer, or to people who handle infected deer or are bitten by infected midges.

Deer typically die within 5 to 10 days of infection. First, infected deer lose their appetite and fear of people. They grow progressively weaker and often salivate excessively, then as the disease progresses, they breathe heavily and develop a fever.

Eight to 36 hours following the onset of observable signs, infected deer pass into a shock-like state, lie down and die, although an estimated 25 percent survive and become immune to future EHD infections, unless it is a different type from the one they had.

Serotype 1 is the one that first hit New Jersey in 1955, but in recent years, Serotype 2 of EHD has killed deer in the state.

"The weather in New Jersey this summer is typical of years in which we have experienced rather large EHD outbreaks--a dry spell followed by an extremely wet July and August producing lots of midges," said George Howard, retired director of the Division, who recalled earlier outbreaks.

"Sick and dead deer, near water, begin to show up in August, and the disease persists until a good killing frost in the fall does away with the midges," he said, and added that the disease isn't carried over in the herd from year to year.

Koch and Deputy Refuge Manager Steve Henry reported one of the area's first deer deaths to the Division after the hurricane after a deer wandered onto the road and died outside the Raptor Trust in Millington, a raptor rehabilitative center on the border of the refuge.

It is difficult to estimate the number of deer killed by EHD outbreaks. After the Salem County area outbreak in 1999 the Division said the disease killed about 4,000 deer. The estimate was gained by comparing the 1999 deer harvest to other years in the same area.

"The Division is asking the public to report any deer showing symptoms of the disease to help us monitor the impact on the local deer herd," said David Chanda, Director of the DEP's Division of Fish and Wildlife.

After the fall bowhunting season for deer opens on Saturday, there should be more reports of sick or dead deer found after thousands of archers take to the woods.