Pond Boss Forums INTRO Questions & Observations EHD Hits Southern Illinois Deer

We've found two dead whitetail bucks near our pond within the last 3 weeks. When deer contract this gnat-born virus they get Epizootic Hemorrhagic Disease (EHD). Within about 3 days they die from fever and internal hemorrhaging. They are often found near water because they get so thirsty from the fever. It is really sad, but it is nature's way of culling the herd I suppose. Has anybody else had this pop up this summer because of the drought and heat? At least two neighboring counties to us have been hit. We are in Hamilton County, IL. The virus does not affect humans. It is not like CWD. There is nothing you can do to stop it or prevent it other than spraying for insects. It will go away after the first hard frost. I hope we don't lose too many more...

I'm waiting for CWD or something to hit the herd here. They have just gotten so incredibly thick wrt 20 years ago. I can remember entire days hunting without seeing any deer; now I'll see a dozen or more without trying.

Isn't excessive heat a factor too?

Yes it is, Cecil. I read that you get much more insect activity/hatching when it is dry. I also read one article that said the gnats lay eggs in the deer's nostrils. We had almost two months of 95+ degree days, several 100+ days, and very little rain. We just got some rain this past week but not nearly enough.

As a taxidermist when I used to mount deer (specalize in fish now) I used to find insect larvae in the nostrils of deer. I assumed they were "deer fly" larvae but since I'm no expert I don't know it that's what they were.

IT is the worst year I have seen in awhile. EHD may also be familiar to some as blue tongue. I have had reports come to me from Tn, Ohio and Western KY as well. It is indeed worse in high extended heat years. Anti hunters need to read about this natural death, it is not pretty at all. Nature is not disney world that is for sure.

We are having the worst/most widespread outbreak in years here in Tennessee. Supposedly, there are some cases every year. However, because of the extreme drought and heat deer were more concentrated around existing water sources which makes them more succeptable to it. However, the biologists do not expect any long term consequences, just short term hits on local populations.

EHD/BT has more impact on white-tailed deer than other naturally occurring disease I have seen. It is a virus that is spread by one vector, a tiny "no-see-um" midge (true fly family) of the genus Culicoides. The degree of sickness resulting from an infected bite depends on the virulence of the virus at that stage. We look at symptoms, clinical signs and disease progession in 3 forms; 1)peracute is very rapid sickness leading to death (hours); 2)acute is more classic type development with slow death (days-week)); 3)chronic is very slow or apparent recovery (months-year). More incidence of chronic is being suspected all the time...the infected deer may not die until the next hot season. The most common host of this pathogen is cattle. In some SW states, 90% of all sampled cattle test positive for EHD, but never get sick or show symptoms.
Although the female midge(the only one that bites) can theoretically pass the disease into unborn eggs, most EHD comes from an adult female midge that bites infected cattle, then deer.
The disease runs parallel with hot temps because of the correlation with the life cycle of the midge in most regions (June - October). The midge larvae are aquatic, like mosquitoes, and depend on fluctuating water levels (wet-dry, high-low) to complete their metamorphosis. They prey on large warm-blooded hosts, usually within 300ft of birthplace. Midges come out in very early morning or at dusk; they dislike direct sunlight or wind. The males hide in nearby vegetation and drink plant juice.
EHD outbreaks can cause 25%-50% mortality in wild herds.
Vector control is the best way to keep midges at bay around your wetlands. Permectrin, water soluble, 10% concentrate in a sprayer will kill midges and is safe on visiting deer.
I have done extensive field research on this disease and its control--info available on request.
Dan

badda-bing...thank ya, Mr V-S
What's the story with the nostril nest?

Thanks, Dan, for all of the great info. Maybe area cattle herds need to be tested by the state in counties where a high number of EHD deaths are occurring? Another question...is it worth it or practical to spray around the perimeter of a 1-acre pond? If so, how wide an area from the pond edge would be necessary? If Permectrin is water soluble will it wash off plants with a rain?
Please feel free to PM me with info if necessary. BTW, if this thread needs to be elsewhere please move it, oh gracious moderators. Thank you.

I highly doubt anyone could see midge eggs in deer nostrils since the adult midge is almost too small for viewing with the naked eye.
I have seen documented reports of live midge eggs/larvae in fresh cattle manure (cowpies) near water puddles. The hatched aquatic larvae require water/excessive moisture for mobility.
NASAL BOTS are the larva layed in mouth/nasal passages of deer by adult female fly, Cephenemyia. They are not uncommon, are very visable (up to 1 in long) and rarely have any significant impact on deer health.

Dan

Claybird, good questions; Permectrin 10% is expensive (about $50 per gallon). The dilution is about 20:1. It is highly bio-degradable and will dissipate rapidly with rain, dew, direct sunlight, etc. We have great success spraying every other p.m. with a high pressure orchard fogger (pto mounted). Although you will accomplish some midge reduction and a lot of mosquito control in small pond/wild habitat senerios, greatest effect is realized in captive deer pens or high-fenced range. Always concentrate spraying on shorelines and shallow stagnant puddles.
The alternative is using more residual pesticides like the organophosphates (Malathion type) but they often cause hyper-sensitive reactions in deer and other wildlife.
Testing more cattle probably won't help the EHD problem in deer herds because cattle rarely get sick from it, they just carry it. Therefore most cattle people are not concerned whether they test positive or not. That attitude will change quickly if EHD ever mutates into human disease...E-bola, SARS, Avian flu, Mad cow, etc did!
Dan

I wonder what the general public would think about their nicely pink Kansas City strips harboring viruses albeit harmless ones!

One more question...would either pesticide harm fish/animals in the pond?

Use great caution with organophosphates in any outdoor application. Permectrin is extremely safe on large wild mammals and livestock when applied at correct dilution rate.
As far as ponds/lakes, etc., you need to ask a Pond Boss...I keep my head above the waterline, you know.
Later