Inside Alberta caves, biologists are fighting a fungus that is threatening bat colonies

Parks Canada biologists are deploying probiotic bacteria in Alberta caves to combat white-nose syndrome, a deadly fungal infection. According to biologist Nina Veselka, the disease threatens the province’s hibernating bat populations, with some sites facing potential local extinction after seeing a sharp increase in winter fatalities.

How does white-nose syndrome affect bat populations?

The disease is caused by a fungus that thrives in cold, damp environments like caves. It enters bat tissues and manifests as a fuzzy, white growth on their wings and snouts, according to Nina Veselka.

The infection forces hibernating bats to wake up prematurely. This drains fat reserves that can’t be replenished during winter, which Veselka says puts the animals at risk of starvation.

The fungus can kill as much as 98 percent of a bat colony, though it poses no risk to humans. In March, a Parks Canada monitoring team found about 69 dead bats at a Jasper National Park cave, compared to three deaths per year for the previous two years, Veselka reported.

Did You Know? White-nose syndrome was first found in Europe in the early 1900s, but it didn’t appear in Alberta until 2022.

What treatment is being used to stop the fungus?

Crews are spreading probiotics containing four bacterial strains at known maternity roosts in Jasper and some confirmed attic roosts. Veselka stated these strains inhibit the growth of the fungus.

The probiotics are applied where bats roost so they can transfer to the bats’ faces, tails, and wings. Veselka compared the process to using hand sanitizer to prevent germs from establishing on a surface.

While Alberta uses these strains to treat existing infections, British Columbia is using them as a preventive measure because the spread has not yet taken hold there, according to Veselka.

Expert Insight: Samantha Carter notes that the slow reproductive cycle of bats—typically one pup per year—creates a high-stakes scenario where colony losses may take a very long time to reverse.

Why is the loss of Alberta’s bats significant?

Evidence of the fungus has been found in three Rocky Mountain caves and Cadomin Cave, which is the province’s largest known hibernation site. In March, Veselka and her team counted 615 bats at that location.

Protecting Bats from White-Nose Syndrome in BC Parks

Veselka warned that survivors may not be numerous enough to huddle for warmth or reproduce. She expects an explosion of infections as bats spread the fungus to one another.

Lisa Wilkinson, a biologist and bat specialist for the Alberta government, said the decline of bug-eating bats could cause mosquito and agricultural pest populations to rise.

What happens next for Alberta’s bat colonies?

The Alberta government has expanded its treatment plan, adding five new sites to the two treated last year, according to Wilkinson.

Recovery may be slow due to low birth rates. Wilkinson stated that while research continues, there isn’t currently a “silver bullet” to cure or eradicate the fungus.

Local populations could face further declines if the probiotic treatments fail to slow the fungal growth across critical habitats.

Frequently Asked Questions

What is white-nose syndrome?
It is a deadly fungal infection that grows in cold, damp areas and affects hibernating bats by draining their fat reserves and causing starvation.

Does the fungus affect humans?
No, according to Nina Veselka, the fungus poses no risk to humans.

How are the probiotics applied?
Crews spread a blend of four bacterial strains at the entrances of maternity roosts and inside some attic spaces so the bacteria transfer to the bats’ bodies.

Do you think proactive preventive measures in neighboring regions are the most effective way to stop the spread of wildlife diseases?