Unexplained deaths of at least four ungulates around the Banff townsite has led Parks Canada to test for possible disease in the local deer population.
The federal agency isn’t speculating until tests come back from the lab on the causes of the death of one elk and three white-tailed deer, including whether or not it could be chronic wasting disease (CWD) – a fatal disease that has yet to be detected west of Calgary or Edmonton.
Officials say a necropsy – essentially an autopsy to determine the cause of death in animals – has been done on each of the four dead animals and appropriate samples sent for testing.
In addition, Banff National Park resource conservation manager Bill Hunt said about 10 deer, primarily from the mule deer population, are being captured so blood samples can be taken for testing.
“There’s lot of things that kill ungulates and we’ll know more when we get the results back,” said Hunt.
“Right now it’s too early to speculate. It could be coincidence that four animals died of natural causes, or it could be some type of disease.”
The first of the unexplained deaths was a white-tailed deer fawn near the Cave and Basin National Historic Site on June 28.
In the months that followed, an adult white-tailed deer buck was found dead by the Bow River upstream in Banff on July 8; an adult female white-tailed was discovered by the Vermilion Lakes turnoff Aug. 22; and an adult cow elk near the March Loop on Oct. 19.
Hunt said if these deaths had occurred anywhere else in the country, they might have simply gone unnoticed and not investigated.
“We have such a busy front country area and our team is very vigilant that this is being followed through,” he said. “There’s absolutely no reason to be alarmed or concerned. This is part of our surveillance for invasive species and disease.”
Many diseases can kill ungulates, including CWD, a progressive, fatal disease known to naturally infect cervids such as white-tailed deer, mule deer, elk and moose.
The disease is spreading westward throughout Alberta, and the most recent count by Alberta Environment and Parks puts the number of CWD cases in wild deer in Alberta since September 2005 at 592.
In conjunction with the 2017-18 hunting season, the province has a CWD surveillance program underway, in which hunters can hand in the heads of ungulates for testing.
Alberta Environment and Parks says there are significant overall patterns of disease occurrence in Alberta.
“CWD continues to occur primarily in mule deer in comparison to white-tailed deer, despite testing large numbers of both species,” according to the department’s website.
“Male mule deer are the most likely, and female white-tailed deer the least likely to be infected with CWD.”
In 2016-2017, the department tested 5,112 ungulate heads and detected CWD in 179 animals – 178 deer and one bull elk. As in previous years, most cases were mule deer, particularly bucks.
In the surveillance sample, CWD was again detected beyond the known range in the province, further up the Red Deer River northeast of Calgary, in the Battle River watershed south east of Edmonton and Vermilion River watershed east of Edmonton.
A discovery of the disease in a white-tailed deer northeast of Fort Saskatchewan is a significant westward extension of known cases in the North Saskatchewan River watershed.
“These units are adjacent to previous cases and indicate further geographic spread of CWD along major waterways,” according to the government website.
Parks Canada sends blood samples it has been taking from the local deer population to the Canadian Wildlife Health Cooperative in Calgary, which determines the appropriate lab for testing.
