Mites infesting bighorn sheep

Authorities are keeping an eye on a mite infestation in the Ashnola Similkameen bighorn sheep population.

"A few years before 2011, we noticed bighorn sheep with funny ears, but we couldn't get any kind of confirmation," said Helen Schwantje, a wildlife veterinarian with the Ministry of Forests, Lands and Natural Resource Operations. "Then, in February 2011, a member of the public took a photo of a young ram in poor condition, just outside of Olalla. It was a disturbing picture, a horrendous picture."

The animal was euthanized, and testing confirmed it was the psoroptes mite.

The mites can cause severe disease in which animals develop heavy crust in and around their ears and other locations and lose their hair. 

"We hadn't seen these mites in Canada before," said Schwantje. "So I requested a regarded biologist to do an aerial survey."

It was determined about 54 to 55 per cent of the sheep were impacted.

In 2013, a ministry report on the Ashnola Siilkameen bighorn stated the disease could have implications on the herd's health. It says psoroptes has contributed to declines in at least one bighorn population in New Mexico, and several American populations live with the mite.

Schwantje said while authorities continue to monitor the situation, there is not a lot they can do.

"We can't catch all the sheep and treat them, and it's extremely difficult to treat," she said. "But we remain concerned and are taking steps."

Concerns about helicopters disturbing the sheep have also been addressed.

B.C. Parks and Fish and Wildlife staff met with Penticton-based HNZ Topflight in the fall to discuss concerns over the health of sheep in the Snowy Protected Area. All parties agreed to explore changes to flight training to minimizing impacts to the population.

The province has received landing site locations from HNZ, and staff have overlaid them with important sheep habitat and provided options on time of use in certain areas. A follow-up meeting is being planned for February or March.

"If we see wildlife, we veer off and don't go there, and we keep a record," said HNZ general manager Don Venturi. 

The ministry is beginning a research project this winter that will include GPS collaring and monitoring of bighorn sheep in the psoroptes-affected area. The project will include spring aerial surveys as well as ground monitoring.

Residents are urged to report sightings of suspected cases to the Ministry of Forests.


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