Gene Chague | Berkshire Woods and Waters: Chronic wasting disease is a scary subject

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Massachusetts Division of Fisheries and Wildlife Moose and Deer Project Leader David Stainbrook attended the October Berkshire County League of Sportsmen meeting to discuss Chronic wasting disease, a disease that affects cervids (members of the deer family). The League delegates were hoping that because there weren't many new cases reported in nearby states, our state would ease up on the restrictions over bringing them into Massachusetts. Currently, the regulations state that it is illegal to import, process, or possess whole carcasses or parts of any cervids from states or provinces where CWD has been detected. It is legal to import deer meat that is de-boned, cleaned skull caps, hides without the head, or a fixed taxidermy mount. No live deer, of any species, may be brought into Massachusetts for any purpose.

Well, I suspect the sportsmen will have to wait a long time before that restriction is lifted.

Stainbrook's talk was very important and informative. I will attempt to paraphrase what he said in this and next week's column.

CWD was first discovered in 1967 in Colorado at a penned-in facility when 12 mule deer became emaciated and died. Biologists had no idea of what caused it and thought it was a virus of some sort. It wasn't until 1978 that they figured out that it was basically the same kind of disease that sometimes exists as scrapie in sheep and mad cow disease in cattle and caused by a protein. Once it gets into the animal's system it causes brain damage and certain death. But they still didn't know enough about it, and why and how it spread.

Biologists developed several hypotheses about how it originated. Perhaps it was already present in the wild and brought it in to the Colorado pen. Another was that there were nearby pens that were raising sheep and maybe it was scrapie that mutated to infect deer. No test for CWD was available until 2003. Much was still unknown about how it spread. Thus, movement of captive deer across state lines was not known to be a risk factor at the time, which allowed the disease to spread throughout the country relatively undetected, with hunter-harvested deer movement also being a potential route. The very first wild case was an elk in Colorado in 1978 and through the next 30 years it spread to white tail deer, elk and other cervids.

In 2005 they first discovered it in Oneida County, N.Y. Five captive deer in two different farms tested positive. Somehow, CWD escaped from the farmed deer into the wild population and biologists found two wild deer with it. Was it caused by deer escaping and getting in contact with wild deer? Was it caused by those wild deer coming into contact with the penned-up deer (nose to nose)? Was it from a deer carcass that was brought in from one of the CWD positive states?

Meanwhile, CWD showed up in West Virginia, Pennsylvania, Virginia and Maryland. Luckily, they have not found any in New England, but the recent discovery of it in Quebec (just about 100 miles from the Vermont/New York border) is concerning.

According to Stainbrook, tests in one area in Wisconsin revealed that half of the bucks tested are infected, but to look at them you would never know. The adults don't become symptomatic until 18 months or longer. You can have what appears to be a healthy deer and never know it is infected, but is spreading infectious material across the landscape. They looked at every hunter that took a deer from that area and determined where they brought the carcasses — which was all over the country, highlighting how quickly it can be spread if those hunters did not follow current regulations on importing carcasses. That's the thing that worries the biologists.

Around 2008 the federal government allocated $15 to $18 million for testing, allocating the monies among all of the states. It costs anywhere from $25 to $50 to test a carcass, and the costs add up very quickly when there are thousands of deer to test.

In 2012 most of the federal funding disappeared and states had to severely cut back in testing. Many had to get rid of all CWD employees. This possibly explains the drop in reported CWD cases and why it appeared to look like the disease was decreasing.

When the federal monies were available, scientific tests discovered that CWD exists as mis-folded proteins called prions. One of the first things they found out was that if it was in the spinal cord and if another deer got in touch with it, that would spread the disease. Then they found out that not just saliva and blood could cause its spread, but also that feces and urine could, as well.

Another study found that when CWD goes onto the ground from the urine and feces, it can last in the soil and be infectious for 10 years. If it binds to the soil particles, it becomes even more infectious. They subsequently found out that plants absorb it and CWD doesn't wash away with rain. Even most incinerators are not hot enough to kill it. Bleach apparently does work.

Because it is taken up into the plants, there are whole new issues because of the agricultural products that are coming out of the states that have high incidences of CWD like Wisconsin, where they have corn, alfalfa, soybean and all products that are going into our food and livestock. They found that crows eating on deer carcasses could also spread it.

"There is a potential for it to be spread throughout the country," said Stainbrook.

The scary part is that many deer look healthy, but they may have it and it may take two years for them to show symptoms and die from it.

"They are spreading it well before we can tell that a deer has it," said Stainbrook.

Are there any human issues? Are the people who have been eating deer affected? So far nothing has come up (incidentally, cooking the meat at oven temps will not get rid of prions). Fortunately, only deer and other cervids get it. More on this subject next week.

Archery deer hunting season opens tomorrow

In Zones 1 through 9, archery deer hunting season opens Monday, and runs through Saturday, Nov. 24, excluding Sundays. The regulations state:

— Hunting hours begin 30 minutes before sunrise and end 30 minutes after sunset. (Except on Wildlife Management Areas stocked with pheasant or quail during the pheasant or quail season, hunting hours are sunrise to sunset.)

— Only archery equipment can be used during this season.

— Arrows must have a well sharpened steel broadhead blade not less than 7/8 inches in width. Expanding broadheads are legal.

— All bows must have a draw weight of at least 40-pounds at 28 inches or at peak draw.

— Poisoned arrows, explosive tips, and bows drawn by mechanical means are prohibited.

— Crossbows may be used by certain permanently disabled persons by permit only.

— During archery season, hunter orange is not required unless on a WMA stocked with pheasants

— Season limit is two antlered deer per year in Zones 1 through 9 and as many antlerless deer as you have valid antlerless deer permits for.

— Reporting is required within 48 hours of harvest

— There is no daily limit. If you have unused antlered tags or antlerless permits, you may continue hunting after reporting your harvest.

Be careful out there in your tree stand. We don't want to be reading about your falling out of it and becoming a fatality. Also, be mindful of ticks.

Gene Chague can be reached at berkwoodsandwaters@roadrunner.com or 413-637-1818.


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