Leading bat biologist Cori Lausen is on a mission to protect B.C. bats from white-nose syndrome (WNS), a fungal disease that kills bats in winter hibernation. Since 2006, WNS has spread from a single site in New York to 36 states and seven Canadian provinces. In 2018, it appeared in Manitoba and just this past spring spread to the east side of the Cascade Range in Washington, nearing the U.S. Columbia Basin.
“The Columbia River is thought to be a major thoroughfare for bat migrations, which means WNS could show up in the Kootenays pretty quickly,” said Lausen.
Based in Kaslo, Lausen is an Associate Conservation Scientist with Wildlife Conservation Society Canada (WCS Canada), which has an on-the-ground project in the West Kootenays that aims to bolster bat populations pre-WNS and set the stage for quicker population recovery post-WNS. The project, which received Kootenay Lake Local Conservation Fund support in 2019, began by evaluating bat boxes as a tool for bat conservation.
Bats are protected under the BC Wildlife Act. Of the 16 confirmed species of bats in B.C., half are listed as vulnerable or threatened. At least 11 bat species are found in the West Kootenays, which is a hub for provincially significant maternity roosts.
What Lausen has discovered is that while bat boxes offer an alternative roosting site when bats are evicted or barred from a building, these structures can overheat in the more frequent summer heat waves, leading to direct mortalities and may lower reproductive success.
“The problem is that female bats are philopatric, which means they go back to the same place they were born, and their female pups do the same. When suddenly the roost isn’t there anymore — someone has closed it up, the building has been knocked down — they look to the nearest spot in their home range, see a bat box, and into it they go. When it gets too hot, they can’t move around like they could in a building roost. They’re just sitting ducks.”
Nursing bats and their pups need different options within a close range, somewhere to fly quickly to if they need a cooler spot. For bat boxes to be effective, Lausen is promoting the idea of placing four or five in different places on a property in different levels of shade. And bigger structures — bat condos instead of boxes — to better imitate the building roots that bats find so beneficial. Several bat condos have already been built in the Creston area.
“Bats used to roost in valley bottom rock and tree crevices (before widespread logging, human development and flooding from the Columbia River dams), and switch roosts to find just the right conditions they need. What we’re saying is we need to re-create the forest again. Giving bats one bat box is like saying ‘here’s one tree.’ The chance that one tree does everything they need is zero.”
The next phase of the project involves rolling out a probiotic spray Lausen and partners have been developing. In natural roosting sites, bats come into contact with microbes in the soil, some of which can prevent the growth of the WNS fungus. Bats roosting in bat boxes and buildings made of plywood don’t come into contact with these natural anti-WNS microbes. By spraying a mixture of these soil microbes and powdered clay into empty bat boxes, a rock crevice environment is imitated. When bats roost in the box, the beneficial microbes become part of their natural wing flora, which could protect them from WNS.
“It is actually a competition on their wings among microbes,” said Lausen. “We’re doing this as a Robin Hood effect to make sure more bats get these good bacteria.”
The prototype kit consists of a spray can of air and vial of clay containing the probiotics. A field pilot was done in Vancouver last August, but the project isn’t at the distribution stage yet. When it is, Lausen is hoping landowners will help.
“If we can get landowners to become citizen scientists and apply the spray to their bat boxes, this can help us save bats around the province,” she said. “The BC Community Bat Program, including Kootenay Community Bat Project, has been working with landowners for many years to identify major roosts.”
Lausen’s background in bat biology and research is unparalleled. With a PhD in bat landscape genetics and roosting ecology and a MSc in bat ecophysiology and behaviour from the University of Calgary, Lausen has captured over 15,000 bats and over 30 bat species, been contracted to do bat-related work for numerous Canadian and U.S. agencies, led dozens of bat-related scientific projects, authored over 50 peer-reviewed articles and government reports, and is the recipient of 15 academic and conservation awards (to name a few of her career highlights). She’s even worked as a high school science teacher.
It all started, she often jokes, with love at first bite. As an undergrad, Lausen had the opportunity to work for a professor who was studying bats. The very first bat she held was out of an attic in Medicine Hat. It was banded — and it bit her.
“It had a band on it so we knew its rough age, and it was older than me, and I thought ‘how is it that a tiny little animal can live that long’? That’s when I got fascinated by them. Literally that first bite I thought, what are you guys doing that’s so cool?”
To bring people on side, Lausen likes to get across to landowners how long-lived bats actually are. They live 30 to 40 years and are slow to reproduce — they have just one young per year, and there’s a 50 per cent change that young won’t survive. A mass mortality would have a devastating effect and, as Lausen also points out, bats are beneficial to have around. Bats are the primary predators of night-flying insects and important insect control for healthy ecosystems and resource economies, including forestry. Declines in bat populations could negatively impact both aquatic and terrestrial ecosystems, and even result in economic losses and increased pesticide use.
Her outlook on the future of Kootenay bats in the face of the imminent threat of white-nose syndrome?
“Cautiously optimistic,” Lausen said.