Chronic Wasting Disease (CWD) surveillance update in Alberta

Alberta Envionment

Like so many things lately, the 2021-22 CWD season faced many unexpected challenges. These included considerable field challenges during hunting seasons, frozen water pipes at 2 of 3 labs where CWD sampling occurred, supply chain issues with receiving essential lab materials, and of course, overarching concerns and limitations associated with the COVID pandemic. However, despite these challenges, the CWD surveillance program delivered test results for over 11,000 heads submitted to the program. We heartily acknowledge and thank all those who help make this program such a success and look forward to your continued support.

In 2021-22, we received 11,086 heads of which 10,909 were suitable for CWD testing. The disease was detected in 1,156 wild deer and elk (10.4% overall: 984 mule deer (594 males, 390 females), 164 white-tails (134 males, 30 females), and 8 elk (1 male, 7 females). CWD was not detected in moose in Alberta this year. A map and summary tables of the 2021-22 results are provided in the CWD Map and Statistics section below. Looking more closely at the data for 2021-22, CWD was found in:

• 14.4% of 6,816 mule deer

• 4.4% of 3,738 white-tailed deer

• 2.4% of 333 elk (primarily from CFB Suffield)

• 0 of 173 moose

• 0 of 16 other wild cervids, most of which were caribou

Of the 10,501 deer for which gender/sex was reported, CWD was detected in:

• 22.1% of 2,685 male mule deer

• 9.5% of 4,097 female mule deer

• 5.4% of 2,500 male whitetails

• 2.5% of 1,224 female whitetails

• Analyses of previous data determined the weighted CWD occurrence in Alberta is:

• Mule Deer: male 1.00 female 0.4

• White-tailed Deer: male 0.3 female 0.1

• Thus male mule deer are the most likely, and female white-tailed deer the least likely to be infected with CWD.

• The geographic distribution of CWD is clustered in some WMUs but continues to expand westward.

CWD continues a steady progression westward, particularly along the Bow river corridor northwest of Calgary. It was detected for the first time in ten WMUs on the western and northern perimeter of the CWD area (104, 216, 224, 302, 314, 502, 506, 510, 514, and 936).

For 2021-22 the basic program was much the same as in the past. In order to better support game management decisions, surveillance is focused on designated areas along the eastern border and along the northern and western perimeter of the CWD affected area (see the map on our CWD Information for Hunters page). Mandatory areas on the Alberta/Saskatchewan border allow deer managers to track the trajectory and outcome of disease in areas where CWD has existed the longest and is likely to have its greatest effect on deer populations over time. Mandatory areas along the northern and western edge of areas where CWD is enzootic (established) are used to track the continued spread of this invasive disease in our deer populations.

As in previous years during the rifle seasons, 24-hour freezers are placed strategically throughout the mandatory areas to make it easier for hunters to drop off heads for testing. Instructions and materials are provided at each freezer. Please remember to fill out both sides of the green CWD labels with all the requested information, and remember to keep the bottom portion of the label as it has the CWD number associated with the head you submitted. Also, please use one label for each head you submit but DO NOT take extra labels from the freezers. Leave them for other hunters to use.

Note that the head drop-off freezers are only available from mid-October to midDecember. Deer heads can also be dropped off at Fish and Wildlife offices throughout the year during office hours. However, there may be COVID-19 limitations and hunters are encouraged to call an office to determine local head submission options. See page 13 of the 2021 Alberta Guide to Hunting Regulations for office locations and phone numbers. For further information, see: Chronic Wasting Disease – Information for Hunters.

All hunters who submit a head receive their test results in an email using the email address in their AlbertaRELM account. Hunters without an email address in their account are phoned only if the animal is positive for CWD.

The total number of CWD cases detected in wild deer in Alberta since September 2005 is 4,741.

Free CWD replacement licences no longer available

The original intent in offering replacement licences was to encourage hunters to return to areas of Alberta where CWD was first detected. However, hunter interest and harvest in the CWD area remains high and free replacement licences are no longer necessary.

Initially, very few harvested deer had CWD and thus very few replacement licences were offered. However, with increased prevalence and distribution of CWD, this is no longer the case.

Increasing numbers of hunters with a CWD replacement licence are creating a disproportionate harvest opportunity and advantage over those hunters who must build priority points to access a licence, particularly for antlered mule deer.

CWD occurs in pockets of localized deer, so hunters harvesting from the same small population each year are more likely to harvest an infected deer and gain access to annual free replacement licences. As the number of CWD cases increases over time, the number of replacement licences becomes disproportionate to the number of licences available to individuals who apply for draws, and limits the diversity of opportunity for broader populations of hunters who wish to have that opportunity.

CWD and human health

While there are no known cases of CWD in humans, health authorities recommend precautions. Additional information is available at: CWD and Public Health.

Thank you to hunters, guides and landowners

It is hard to believe Alberta Environment have been tracking this disease in wild deer in Alberta for over 20 years. Alberta began CWD hunter surveillance in 1998 and has one of the best continuous datasets documenting the occurrence and patterns of CWD in wild cervids, specifically in prairie / parkland ecosystems. The continued support of hunters, guides and landowners is the basis for the strength of the surveillance data.

Attention hunters

In order to track chronic wasting disease in our deer populations, submission of deer heads for CWD testing is mandatory in specified WMUs in designated areas in Alberta. Submit deer heads for CWD testing during rifle seasons at any of the 24-hour freezers in Edmonton, Calgary, and across eastern Alberta.

Note that the deer head drop-off freezers are only available from mid-October to midDecember. However, CWD surveillance in Alberta is a year-round program and suitable frozen deer heads can be submitted for testing at a Fish and Wildlife office throughout the year. Phone ahead for office hours and drop-off locations.