Colorado Biologists Continue to Track Distribution of Fatal Wildlife Disorder
Continuing their search for better information on distribution and occurrence of chronic wasting disease(CWD) in Colorado’s deer and elk herds, state wildlife officials are implementing a new electronic network of handheld computers to streamline surveillance of the fatal neurological disorder.
The Colorado Division of Wildlife (DOW) believes the new system will simplify paperwork for hunters and field officers, and make it easier for biologists to estimate with more accuracy CWD prevalence across the state. Above all else, the system was designed to make it easier and faster for hunters to obtain test results.
“We’re trying to create a system that actually makes it happen as quickly as possible,” said biologist Kathi Green, CWD coordinator for the DOW. “We worked with every part of our organization to make sure everybody’s needs were met.”
Green said the agency’s goal was to eliminate factors that slowed the testing process last year, when some results were delayed because hunter applications were soiled by tissue specimens and could not be read or photocopied easily.
Under the new system, wildlife workers in the field and lab technicians will use personal digital assistants (PDAs) with built-in bar code scanners to glean vital information they need to track and test game specimens. With more accurate submission information, biologists will have a better chance of tracking the distribution of CWD, pinpointing hot spots around the state, and gathering evidence that could shed more light on factors influencing the occurrence of the degenerative disease in Colorado.
Wildlife officers will use PDAs to scan and enter information on hunter licenses, game species and gender as well as the game management unit (GMU) in which the animal was taken before uploading the data into desktop computers.
Data and specimens will then be forwarded to lab technicians for testing and—once the hunting season has ended—biologists will take the compiled data and analyze them, looking at prevalence patterns and other variables. Colorado will pilot the use of PDAs in labs where technicians will conduct CWD sampling and testing.
Jeff Sanders, chief information officer for the Colorado Department of Natural Resources (DNR), credited collaboration between the DOW, DNR staff and software contractor Access Data Inc. in getting the project off the ground quickly.
Collaborators successfully garnered necessary support from the state Wildlife Commission, the Governor’s Office of Innovation and Technology and the state’s Commission on Information Management, he added.
“This gives every indication of being a successful project, especially since it is so critical to the state and because it was conducted under a very aggressive schedule,” Sanders said. “I hope that all future information technology projects in the department are as successful at meeting the business requirements, while also coming in on time, and on budget.”
DOW’s new electronic system cost about $180,000, including the purchase of 150 handheld computers and Access Data’s tailor-made software. The system is expected to save the division some $80,000 per year in paperwork and data entry, paying for itself in two and a half years. Green said Colorado owes a debt of gratitude to Michigan state wildlife officials, who shared their experiences with handheld computers they used to gather data on tuberculosis in wildlife herds.
In Colorado this year, hunters will be able to submit animal samples at more locations around the state, paying a $15 fee. Fees in portions of southwest Colorado could be waived this year as biologists continue to gather more sampling data in certain regions. Last year, hunters received most results in two weeks. Wildlife officials hope to match or improve on the turnaround time for negative test results this year.
Positive results take longer to process because of more extensive lab work needed to confirm the findings of the initial screening test.
Hunters also will be able to access test results in several ways again this year. Options include an interactive voice response telephone system and the DOW Web site. Last year, thousands of sportsmen used the phone and Web systems to access CWD information.
More than 26,000 deer and elk were tested for CWD in Colorado last year in what was the largest, most extensive wildlife disease survey in state history. Of the animals tested, far fewer than 1 percent of harvested deer and elk showed evidence of infection, and most came from portions of northeastern Colorado where CWD has been found for more than 20 years. As more hunters turn in specimens for testing from parts of the state where data are lacking, the agency hopes to establish a more comprehensive picture of CWD distribution and prevalence in Colorado.
Biologists want to gather 300 deer and 300 elk samples per data analysis unit (DAU) to gain more precision in estimates of prevalence. Last year, sampling goals were reached in 12 elk and 10 deer DAUs, regions comprised of various GMUs that define the geographical area encompassing a herd’s entire summer and winter range.
Based on last year’s survey, biologists concluded in early August that the rate of CWD infection in deer and elk varies from location to location.
CWD has not been detected across large portions of the state. However, biologists say its prevalence has increased in two northern DAUs where they have monitored trends in adult male mule deer since 1996.
Biologists expect continued annual assessment of such trends to aid in evaluating the effectiveness of disease management programs in the region.
Based on last year’s data, CWD is more widely established in Colorado than biologists previously believed, said DOW Veterinarian Michael Miller.
“We had hints of that from the spring of 2002. I think everybody was hoping against hope that it wasn’t as widespread as it turned out to be,” he said.
Miller said testing has greatly improved biologists’ understanding of the distribution of CWD. Last year, for instance, they learned the disease is more prevalent among elk than deer in the Middle Park area west of Rocky Mountain National Park. CWD usually is found in higher prevalence in deer herds, Miller said.
The good news is that infection rates in newly discovered areas were relatively low. Biologists say the recent discovery of CWD in southeastern Utah does not mean the disease is widespread in the region.
No cases have been reported on the Ute Mountain Ute Reservation, and none have been detected in surveys of the Uncompahgre Plateau.
Miller said this year’s CWD testing efforts will focus more on the southwestern part of the state because hunters have submitted fewer samples there.
“We want to shore up data in the southwest part of the state a little more,” he said. “It’s just a hole in our statewide data right now.”
The DOW has more than adequate sampling from the northern half of the state, with the exception of North Park and GMU 10, in Colorado’s extreme northwest region, the veterinarian added.
Miller said the state’s new electronic system for gathering CWD data will be the biggest improvement in the data-gathering process this year.
“We’re going to have a better way of handling and processing the mass of data that we accumulate so that we should be able to get a handle on distribution and infection rates much more rapidly than we did last year,” he said.
Other conclusions issued by the DOW based on last year’s CWD tests include:
–In northeastern Colorado, where the disease has been present for more than two decades, the estimated prevalence for hunter-harvested elk varied from zero to about 3 percent. Mule deer prevalence in the region varied from less than 1 percent to almost 7 percent. Some local populations of mule deer had twice the rates of infection; –In units where the disease has been detected in northwest Colorado, prevalence in elk ranged from nearly zero to almost 2 percent. Estimated prevalence in deer in units where the disease has been detected averaged less than 1 percent where adequate levels of sampling have occurred.
There is no known cure for CWD, which has attacked wild deer and elk in a number of states and two Canadian provinces.
While the disease is similar to bovine spongiform encephalopathy in cattle and scrapie in sheep, there is no evidence it can spread to humans. Scientists suspect the most likely mode of transmission among animals is via saliva and feces.
For more information on chronic wasting disease, visit: http://wildlife.state.co.us/CWD/index.asp and http://cwd-info.org/