Local deer found to have CWD, Chronic Wasting Disease
CWD, the acronym used to talk about chronic wasting disease, belongs to a family of prion diseases that are relatively new to science. Long-term consequences are not well understood. However, researchers in many Midwest and mountain states have learned a great deal in over 50 years of noting declining health, and ultimate death of deer species with advanced symptoms.
It is infectious. Individuals with this disease shed prions through their saliva, urine, and feces. To make matters even harder to manage, those prions can bind with soil particles, usually clays, and may be taken up into some green plants that deer may subsequently browse upon. There is no doubt that CWD is very persistent and presents a huge problem for wildlife researchers.
A mule deer was the first in Colorado to be diagnosed with CWD over 50 years ago. Reported cases from North America show locations on a map ranging from the Canada provinces of Manitoba and Saskatchewan, and in the states of Montana, North and South Dakota, Wyoming, Colorado, Utah, Nebraska, Kansas, Oklahoma, New Mexico, Texas, Minnesota, Wisconsin, Iowa, Missouri, Arkansas, Illinois, Michigan, Ohio, Pennsylvania, Ohio and New York.
One new report also adds Florida to the list. The tally for infected states is 24, three Canadian provinces, even South Korea and Norway.
All deer family members can be susceptible, but not every deer species in known “hot spots” will become infected. CWD has been detected in elk, moose, caribou/reindeer, white-tailed and mule deer. Once an animal becomes infected, it will take years to manifest into the final lethal stages. Early on, the deer species will appear and act normally.
And wherever the infected animal travels, it will be shedding prions into the environment where other deer may or may not unknowingly become infected. However, over time the animal will not win this contest between the disease vector and its will to live.
There is no vaccine at this time, and if there was, how to administer it to wild herds scattered throughout some of the most inhospitable terrains in the world leads one to question if it is even possible.
When a new CWD locality becomes known, as in the Marshall County case, the percentage of animals that may be infected is quite low, and may stay confined to a small geographic area. Over time, as researchers have found out, the disease slowly increases from contact with other
deer, or at close quarters feeding sites, or from the contaminated environment.
CWD can also spread naturally from animal to animal as some deer move long distances into new territories. Humans unwittingly may be part of the problem if deer are moved from one location to another, or by improper disposal of carcasses from fall hunting ventures.
Long-term studies have found heavily infected geographic areas reach tipping points where the overall population will start to decline by quite a bit. Southwest and Central Wisconsin is just one case in point where this has happened.
There are other known heavy declines from Wyoming and Colorado. Many factors affect CWD’s advance including the habitat, life history of the animals, birth rates, mortality from all other sources, hunting pressure and harvest quotas by individual states.
Male deer species are known to become infected at higher rates than females, and those male deer will die quicker from CWD than females. If prolonged infections through many animals continues, the buck to doe ratio may become skewed and out of balance. If ever there was a problem for managers and researchers seemingly too big to handle, CWD is it.
Early detection offers the best opportunity to eliminate or control CWD. Aggressive methods to remove infected animals through region specific tests and additional hunter quotas of allowed take can help.
More animal testing from hunter harvested deer will for sure be one step to help determine the local infection rate. The Baxter Library informational meeting will explore how additional testing and sampling will be conducted.
Not all is doom and gloom concerning CWD. Still, it remains a difficult situation for hunters, landowners, biologists and wildlife researchers.
Not all deer become infected. Some deer may have the specific genotypes to resist infections from CWD. The whys and hows that is accomplished in some deer and not others is an open question at this time.
Additional open questions are related to how long those shed prions persist in the environment, how readily those prions may get transported into plants that deer may eat, and what are the major sites that tend to infect new animals?
For Iowa deer, during the 2022 fall hunting seasons, over 5,000 had samples removed for lab testing for CWD. Of those, 96 turned up positive, which means 4,904 tests were negative.
Since the year 2002, over 100,000 Iowa samples have been evaluated. What started out in a small location in northeast Iowa and south central Iowa has expanded.
Based on 2022 testing, new counties were added to the positive test locations; namely Jasper, Grundy and Lucas, and most recently, Marshall became a known site from one sample.
To learn more about CWD and its potential impacts, and what landowners and hunters can do working together to slow the spread of CWD, plan to attend the Baxter Public Library meeting on Aug. 29. If unable to attend that meeting, consider another similar meeting set for Oct. 10, at 7 p.m., at the Wellsburg Memorial Building, 501 N. Adams St.
Why did the turtle cross the road? In hopes of getting to the other side — without being run over by the tires of a truck or car. That may not be easy to do when the pace of a turtle is very slow in the first place.
There are thirteen species of turtles in Iowa. They join other reptiles and amphibians on the diverse list of aquatic or semi-aquatic animals. Iowa has 17 frogs and toads, five lizards and 28 snake species.
Wetland habitats are a common theme for all of these. Many lay eggs in water or wetland environments. Turtles lay eggs on land, and when turtles crawl along at a slow pace, often crossing gravel roads or busy paved highways, they become vulnerable to being killed.
Recently, I observed a snapping turtle attempting to cross a busy Highway 330 near Timmons Grove County Park. I stopped my vehicle and used a long handled snow brush to push and prod the reptile, now at the centerline, off the roadway traveled portion.
The snapper did not want to cooperate, but I persisted and got the heavy shelled animal safely into the ditch. A wetland was just across the fence where it could undertake its life undetected.
I have seen the sites where a female snapping turtle selected a roadside or nearby ditch bank as the place to dig a hole with her hind feet. By scrapping bits of sand, gravel and rocks away, she will lay her clutch of eggs.
Then, when that task is done, she uses her rear legs to refill the hole and tamp it down. Now, the rest is up to solar power of warming soil to create the right temperatures for the eggs to incubate and, in about 30 to 40 days, hatch.
The young snapping turtles have to dig their way out of the hole, see the light of day for the first time, and instinctively crawl away toward wetlands or other aquatic habitats. Their tiny brains are hardwired to know what to do.
Many make the long journey to find success. Many may become food for wandering predators like raccoons, owls, snakes, otters or mink. The predator/prey dynamic is always at work on Mother Nature’s landscape.
Ducks Unlimited attempted to have a five station fun clay bird shoot at the Izaak Walton League last Sunday, Aug. 6. Well, Mother Nature had another idea. It was called rain.
Enough rain in persistent showers from light to heavy made for a too wet day. Everyone wanted the rain because the land needed it, but outdoor activities took a hit.
So the DU committee called off the shoot and rescheduled the clay bird event for today, Saturday, Aug. 12 beginning at 9 a.m. This short notice reset hopefully will find you and your shotgun ready for a bit of outdoor practice at fast flying clay birds.
The cost for the shoot is $20 for the first round of 25 targets. If you desire to shoot another round, that cost is just $15. Call Sam Dixon for details at 641-750-6488.
“Give every day the chance to become the most beautiful day of your life.” — Mark Twain
Garry Brandenburg is the retired director of the Marshall County Conservation Board. He is a graduate of Iowa State University with a BS degree in Fish & Wildlife Biology.
Contact him at:
P.O. Box 96
Albion, IA 50005