Leier: EHD, CWD are two diseases that can influence deer populations

West Fargo With deer season in full swing, it's a good time to take a look at a couple of diseases that can influence the state's deer populations. As we all know, wildlife can get diseases, just like humans. In a recent North Dakota Game and Fis...

West Fargo

With deer season in full swing, it's a good time to take a look at a couple of diseases that can influence the state's deer populations.

As we all know, wildlife can get diseases, just like humans. In a recent North Dakota Game and Fish Department webcast, Dr. Dan Grove, the Department's wildlife veterinarian, shared his insight on two different diseases with which many deer hunters are familiar.

To paraphrase Dr. Grove, epizootic hemorrhagic disease, or EHD for short, occasionally pops up. Fortunately, this year Game and Fish has not received any reports of dead deer that would indicate active EHD this fall.

There are two viruses that can cause it. Both are spread by biting midges. There is actually an EHD virus, and there is also what is called bluetongue virus. People use the names interchangeably, but it is actually two separate viruses, but deer can get both.

Historically, EHD has occurred south and west of the Missouri River, but in recent outbreaks since about 2009, we have actually seen an expansion east of the river and north of the river. We have actually had cases as far east as Grand Forks County. So basically anywhere the midge lives there is potential that the disease can exist.

The virus can live in deer, it can live in cattle, so the midge can then spread it from one sick animal to another. Most of the white-tailed deer that get EHD eventually die, and in years when an outbreak is widespread, population loss can be significant.

North Dakota did not have a single case of chronic wasting disease, up until a few years ago, but we do have now.

So far, the state has had seven positive animals - six mule deer and one white-tailed deer - all from deer hunting unit 3F2, which is south and west of the Missouri River and borders against South Dakota.

Dr. Grove says this disease is basically spread through direct contact or movement of infectious materials out of an area, which is why North Dakota has restrictions in place on carcass movements, and specific regulations on what can and cannot be transported in and out of unit 3F2.

Game and Fish has diligently monitored for CWD, targeting specific units and specific areas. This year the focus is the western third of the state - units that are south and west of the Missouri, and units that are west of U.S. Highway 83 on the north side of the Missouri river.

Game and Fish samples deer taken in unit 3F2 every year. This includes collecting hunter-harvested heads, as well as incidentals like road-killed deer. Lymph nodes are collected and submitted for testing.

Dr. Grove reminds North Dakota hunters returning from big game hunting trips to other states that there are import regulations that apply to many areas. Basically, if you are hunting in an area of a state that is known to have CWD, you are going to have certain restrictions, and you need to review the North Dakota proclamation on the Game and Fish Department website, at gf.nd.gov, before you return.

Because of the risk of spreading CWD, hunting big game over bait during any big game season is no longer allowed in units 3F2, 3F1, 3E1, 3E2, and the part of unit 3C that lies west of the Missouri River.