Canadian Wildlife Health Cooperative

09/25/2026

Melanomas in Brown Bullheads of Lake Memphremagog, Québec: A Transmissible Cancer?

In December 2023, this blog reported the discovery of brown bullheads (Ameiurus nebulosus) presenting with black skin masses. Histological analyses had at the time confirmed that these were melanomas, a potentially malignant tumour of melanocytes. This syndrome has been documented in bullheads since 2012 in Lake Memphremagog and Lake Magog, and various hypotheses have been proposed regarding the causes and risk factors of these melanomas, including exposure to ultraviolet rays or carcinogenic chemical contaminants, or a viral origin.

Read the full blog here:

In December 2023, this blog reported the discovery of brown bullheads (Ameiurus nebulosus) presenting with black skin masses. Histological analyses had at the time confirmed that these were melanomas, a potentially malignant tumour of melanocytes. This syndrome has been documented in bullheads since...

09/22/2026

Dr. Laura Bourque (CWHC Atlantic) providing necropsy training to the Marine Animal Response Society (MARS) in Halifax, NS. This endeavour assists in improving fresh tissue sampling for further analysis by a pathologist.

Sometimes the most important answers come after an animal has died.

One of the hardest parts of our work is knowing we can't save every animal.

But every animal still matters.

Through careful examinations, sampling, and necropsies, we can better understand disease, injuries, human-caused threats, and impacts from climate change.

Those answers may help protect countless others in the future.

Even when a life can't be saved, it can still make a lasting contribution to conservation.

Photo credit ©MARS

09/17/2026

Banding Together for Wildlife Health

Animals do not recognize provincial or national borders, and understanding their movements, health, and populations requires many organizations working toward a common goal. At the CWHC’s Ontario/Nunavut node, collaboration is at the heart of what we do. Our partnerships allow us to combine expertise, share information, and build a more complete picture of wildlife health across the province.

Read the full blog here:

Animals do not recognize provincial or national borders, and understanding their movements, health, and populations requires many organizations working toward a common goal. At the CWHC’s Ontario/Nunavut node, collaboration is at the heart of what we do. Our partnerships allow us to combine expert...

09/08/2026

Orthoreovirus infection – How are corvids affected and what does it have to do with One Health?

Avian diseases are a significant topic in One Health. Salmonella, coccidia, avian influenza, and West Nile virus, to name a few, are well known for their potential to In this context, one group of pathogens might not be as “famous”, but may also be a threat to domestic and some wild birds – have you ever heard of orthoreoviruses?

Read the full blog here:

Avian diseases are a significant topic in One Health. Salmonella, coccidia, avian influenza, and West Nile virus, to name a few, are well known for their potential to In this context, one group of pathogens might not be as “famous”, but may also be a threat to domestic and some wild birds – ha...

08/21/2026

A New Global Plan to Protect Wildlife Health, and What It Means for Canada

Headlines about rabies, Ebola, hantavirus, and avian influenza continue to remind us that wildlife diseases not only affect wildlife, but can also affect people, our pets, and our livestock. This is why the World Organisation for Animal Health (WOAH) has just launched a new five-year Wildlife Health Strategy (2026–2030). The strategy sets out an ambitious vision: healthy wildlife, resilient ecosystems, and a safer planet.

Read the full blog here:

Headlines about rabies, Ebola, hantavirus, and avian influenza continue to remind us that wildlife diseases not only affect wildlife, but can also affect people, our pets, and our livestock. This is why the World Organisation for Animal Health (WOAH) has just launched a new five-year Wildlife Health...

08/12/2026

The Buzz about West Nile Virus

Mosquito season is back, and so is West Nile Virus. Each summer, the virus re-emerges across parts of Canada, cycling between mosquitoes and birds, with occasional spillover into humans and other animals. As the 2026 West Nile season progresses, the CWHC Ontario/Nunavut branch is tracking the virus in wild birds and what these detection patterns could mean for wildlife and human health.

Read the full blog here:

Mosquito season is back, and so is West Nile Virus (WNV). Each summer, the virus re-emerges across parts of Canada, cycling between mosquitoes and birds, with occasional spillover into humans and other animals1,2. As the 2026 West Nile season progresses, the CWHC Ontario/Nunavut branch is tracking t...

08/07/2026

Nice to have some positive news to share on a Friday!

08/04/2026

Two river otters from the Soldier’s Bay area in Cape Breton (Nova Scotia) were submitted to CWHC-Atlantic for necropsy.

If you have observed otters exhibiting skin disease in Cape Breton, please contact us at [email protected]. Taking pictures and noting the date, time, and location of the observation would be extremely helpful.

Two river otters from the Soldier’s Bay area in Cape Breton (Nova Scotia) were submitted to CWHC-Atlantic for necropsy. The otters had been spotted in the field exhibiting regions of hair loss on their skin (Figure 1). Both otters had multiple very extensive regions where their fur was either seve...

07/27/2026

The amazing network of people and organizations we work with includes Marine Animal Response Society who coordinated the response to this event with our pathologist, Dr. Laura Bourque.

Understanding causes of mortality in marine animals is just a part of the work we do a the Canadian Wildlife Health Cooperative!

07/25/2026

How long does it take a fungus to travel 3,210 km on the back of a bat? For the fungus that causes White-nose Syndrome (WNS) the journey from Albany, New York, to Fort Smith, Northwest Territories1 took exactly two decades.

Since WNS was first discovered in North America, it is estimated to have killed more than six million bats.

Read the full article on our blog.

How long does it take a fungus to travel 3,210 km on the back of a bat? For the fungus that causes White-nose Syndrome (WNS) the journey from Albany, New York, to Fort Smith, Northwest Territories1 took exactly two decades. That works out to be an average rate of 160.5 km per year or about […]