blake
Life Member
Mississippi River Proves No Barrier for CWD
CEDAR RAPIDS, Iowa (AP) — A recently completed genetic study of deer in Wisconsin and Iowa indicates that the Mississippi River does not present much of a barrier to the spread of deadly chronic wasting disease.
"There might as well not be a river there'' for all the good it does in separating Wisconsin deer, which are infected with chronic wasting disease, and Iowa deer, which have yet to test positive for the fatal neurological ailment, said Krista Lang, an Iowa State University graduate student who wrote her master's thesis on the two-year research project.
"It doesn't look like the Mississippi River has much effect in separating the deer on either side,'' said Julie Blanchong, an ISU wildlife ecologist who collaborated with Lang on the project.
The two coordinated genetic testing on a total of 500 Iowa and Wisconsin deer harvested by hunters from 2006 through 2008. The DNA analysis determined only minor genetic differences between Iowa and Wisconsin deer, indicating that they freely cross the Mississippi River.
Iowa's leading deer biologists say the study strongly suggests the likelihood of chronic wasting disease being eventually confirmed in an Iowa deer.
"The risk is pretty high if you go out far enough,'' said Department of Natural Resources deer biologist Tom Litchfield. "It could show up this fall. It could be another 10 or 20 years.''
DNR wildlife research supervisor Willie Suchy it might take 100 years, but the prospect remains a threat as long as the disease is spreading among Wisconsin and Illinois deer.
Since 2001, the Wisconsin DNR has tested 159,234 deer and confirmed 1,354 cases of chronic wasting disease, said Erin Larson, the agency's wildlife health data coordinator.
The Illinois DNR has confirmed 294 cases of the disease, which has not been shown to affect people or livestock.
In 2009 alone, the Wisconsin DNR confirmed 179 cases and concluded that disease prevalence rates continue to rise, especially in its western management zone, which consists primarily of Dane and Iowa counties, the area where the disease was first found in 2001.
Two cases of the disease have been confirmed in Wisconsin's Grant County, which is across the Mississippi from Clayton and Dubuque counties in Iowa.
Biologists know that whitetail deer are capable of swimming the Mississippi, especially in areas with many islands and shallow backwaters. They also can cross on the ice in winter.
Still, "it would have been great if the study had found marked genetic differences'' between Iowa and Wisconsin deer, Litchfield said, "but the study results suggest the deer go back and forth enough to keep the gene pool well mixed.''
If the disease does become established in the Iowa herd, it won't wipe out the population, but it will likely tarnish the state's reputation as the home of many large-antlered bucks.
Bucks are more susceptible to the disease than does, probably because they travel more and contact more deer, Litchfield said.
Because older deer are more susceptible than younger ones, the disease would yield a younger deer herd, with fewer bucks reaching large-antlered maturity, Litchfield said.
Suchy said the state will continue its monitoring program, testing about 4,000 deer per year, mostly in the counties close to the Mississippi River.
The DNR also will continue to lobby the Legislature for a law that would forbid the feeding of deer with mineral blocks and bait stations. While it is illegal to hunt over such feeders and bait stations, many hunters justify them as a means to improve the nutrition of deer on their property.
Suchy said Iowa deer don't need supplemental nourishment, and the practice congregates deer in areas where their feces and saliva increase the chances of spreading chronic wasting disease.
CEDAR RAPIDS, Iowa (AP) — A recently completed genetic study of deer in Wisconsin and Iowa indicates that the Mississippi River does not present much of a barrier to the spread of deadly chronic wasting disease.
"There might as well not be a river there'' for all the good it does in separating Wisconsin deer, which are infected with chronic wasting disease, and Iowa deer, which have yet to test positive for the fatal neurological ailment, said Krista Lang, an Iowa State University graduate student who wrote her master's thesis on the two-year research project.
"It doesn't look like the Mississippi River has much effect in separating the deer on either side,'' said Julie Blanchong, an ISU wildlife ecologist who collaborated with Lang on the project.
The two coordinated genetic testing on a total of 500 Iowa and Wisconsin deer harvested by hunters from 2006 through 2008. The DNA analysis determined only minor genetic differences between Iowa and Wisconsin deer, indicating that they freely cross the Mississippi River.
Iowa's leading deer biologists say the study strongly suggests the likelihood of chronic wasting disease being eventually confirmed in an Iowa deer.
"The risk is pretty high if you go out far enough,'' said Department of Natural Resources deer biologist Tom Litchfield. "It could show up this fall. It could be another 10 or 20 years.''
DNR wildlife research supervisor Willie Suchy it might take 100 years, but the prospect remains a threat as long as the disease is spreading among Wisconsin and Illinois deer.
Since 2001, the Wisconsin DNR has tested 159,234 deer and confirmed 1,354 cases of chronic wasting disease, said Erin Larson, the agency's wildlife health data coordinator.
The Illinois DNR has confirmed 294 cases of the disease, which has not been shown to affect people or livestock.
In 2009 alone, the Wisconsin DNR confirmed 179 cases and concluded that disease prevalence rates continue to rise, especially in its western management zone, which consists primarily of Dane and Iowa counties, the area where the disease was first found in 2001.
Two cases of the disease have been confirmed in Wisconsin's Grant County, which is across the Mississippi from Clayton and Dubuque counties in Iowa.
Biologists know that whitetail deer are capable of swimming the Mississippi, especially in areas with many islands and shallow backwaters. They also can cross on the ice in winter.
Still, "it would have been great if the study had found marked genetic differences'' between Iowa and Wisconsin deer, Litchfield said, "but the study results suggest the deer go back and forth enough to keep the gene pool well mixed.''
If the disease does become established in the Iowa herd, it won't wipe out the population, but it will likely tarnish the state's reputation as the home of many large-antlered bucks.
Bucks are more susceptible to the disease than does, probably because they travel more and contact more deer, Litchfield said.
Because older deer are more susceptible than younger ones, the disease would yield a younger deer herd, with fewer bucks reaching large-antlered maturity, Litchfield said.
Suchy said the state will continue its monitoring program, testing about 4,000 deer per year, mostly in the counties close to the Mississippi River.
The DNR also will continue to lobby the Legislature for a law that would forbid the feeding of deer with mineral blocks and bait stations. While it is illegal to hunt over such feeders and bait stations, many hunters justify them as a means to improve the nutrition of deer on their property.
Suchy said Iowa deer don't need supplemental nourishment, and the practice congregates deer in areas where their feces and saliva increase the chances of spreading chronic wasting disease.
