A swift-moving shadow over the river at dusk indicates that bats are hard at work eating their fill of insects. An often-maligned creature, bats play an important role in pollination and in balancing insect populations. Like many other creatures in today’s world, they’re under threat from disease and human development.
Western Canada is home to many bats, particularly BC which is home to 16 of 18 Canadian species. Alberta is home to 9 species, while there are 8 different species in Saskatchewan and 6 in Manitoba. Fortunately, a number of different organizations are hard at work raising awareness, providing information, and collecting data needed to monitor and better understand bats in Western Canada. Among the organizations most active in bat conservation in Western Canada is the Wildlife Conservation Society (WCS) Canada. Their projects include the Western Canada Bat Conservation Program, the Alberta Community Bat Program, and BatCaver. Other groups focus on monitoring, data collection, and research. A list of bat research and education organizations is provided at end of article.
Cory Olson, Program Coordinator for WCS Canada’s Alberta Community Bat Program, says the program was initiated to improve the management of bats in Alberta in advance of the arrival of white-nose syndrome. It was modelled after community-based bat programs WCS Canada has been involved with in British Columbia. Alberta’s program is run in collaboration with several staff, contractors, volunteers, and partner organizations, including Alberta Environment and Parks and the Alberta Bat Action Team.
The Alberta Community Bat Program emphasizes outreach and education, responding to public inquiries, maintaining a strong social media presence, and providing educational resources on its website. While the primary focus has been on bats and buildings, the program is now active in a variety of applied research projects to advance bat conservation and recovery in the West as described below.
Bat Habitat – Bridges
Bats live long lives – over 30 years in some cases – and are slow to reproduce as females give birth to a single baby once a year. As a result, they are particularly at risk when faced with habitat loss (for foraging and roosting) and disease (such as white-nose syndrome – WNS).
A survey of bridges in Alberta and Saskatchewan is currently underway to determine the extent to which bats use bridges as both temporary resting places and maternity roosts. They are also collecting guano to work out what species are using the bridges and to test for the fungus that causes WNS. The researchers surveyed approximately 500 bridges last year and found that half of them were being used by bats. These were usually larger concrete bridges. “Bats may avoid wooden bridges because of the creosote and metal bridges because they cool off rapidly at night, unlike concrete which is effective at retaining heat,” Cory says. Bats prefer bridges over slow-moving rivers with a wide riparian area where the bats can find plenty of insects.
Dozens of the bridges are being used by bats as resting places during the day before heading out to feed at night. A lot of them are also being used as temporary resting spots at night with the bats pausing to digest their food between feeding bouts. A few bridges are used as maternity roosts with female bats roosting in large groups that can number over 1,000 bats.
Bats are not overly territorial. Several species will often share space, especially bridges, at night. There are plenty of examples of this involving little brown and long-legged myotis.
There is no evidence that bats harm bridges, but bridge work, such as resurfacing, cleaning, or tearing down, can have a major impact on the bats, particularly if the work is done in summer but also in spring and fall. Disturbing or harming a large colony of bats could have far-reaching consequences for the whole region as bats maintain wide territories. Bridges could be very attractive to bats on the Prairies where they may be the only suitable resting spot for many kilometres.
Bat Habitat – Winter
“Bat behaviour in winter is definitely a mystery,” Cory says. Some Alberta bats, such as the hoary, eastern red, and silver-haired, migrate south, but they may still hibernate when they reach their destination. Silver-haired bats have been documented hibernating around the Great Lakes and warmer regions of British Columbia. Some silver-haired bats from Alberta appear to head west towards British Columbia, but their ultimate destination is unknown.
Bats that hibernate in Canada, such as the various myotis species and big brown bats, may still travel up to 600 km between their summer and winter habitats. It’s believed that hibernating bats make use of caves or deep crevices or fissures, but it’s still largely unknown where they go. “We only know the winter locations for a few thousand Alberta bats, but there are over a million in the province,” Cory says. Big brown bats sometimes overwinter in buildings and that’s the case for a few additional species in BC. Some Saskatchewan bats probably hibernate in Manitoba caves.
The BatCaver program identifies and studies bat hibernation sites in BC, Alberta, and the Northwest Territories. The largest colony to date with over 1,000 bats was located in a West Kootenay region mine.
Bat Habitat – Bat Boxes
The Alberta Community Bat Program is one of many groups participating in the joint Wildlife Conservation Society Canada/Canadian Wildlife Federation survey gathering information on how bats are using bat boxes. The Canada Bat Box Program is asking owners of bat boxes to track the temperature and humidity in their boxes and collect guano samples. The researchers hope to improve recommendations for how bat boxes are used and what designs are most appropriate. This will help make sure bat boxes are not overheating or used in ways that could be harmful to bats. The guano samples will identify which species of bat are using the boxes. The boxes will also be sampled to check for the fungus that causes white-nose syndrome.
Bat Habitat – Farms
The Alberta Community Bat Program is currently collecting guano to support an Environment Canada study to detect for neonicotinoids as a first stage in determining whether bats are being exposed to this class of pesticides. Studies on Asian insectivorous bats suggest neonics could affect the animal’s echo-location ability, which could impact their survival, but the subject is largely unstudied.
WCS Canada plans to work more closely with agricultural communities in future. Bats are often found in barns and other farm buildings, and WCS would like to better understand how bats use these areas, particularly in terms of reducing the number of insects harmful to crops. Bats often take advantage of cattle by feeding off the insects the bovines have stirred up. This could possibly benefit farmers by providing free, organic insect control that would improve crops. “A study in the United States estimated that bats provided a $53 million pest control service on corn crops,” Cory says.
“Migratory bats travel large distances, and that places them at extreme risk from wind farms,” Cory says. “There are approximately 1,000 turbines in Alberta at the moment and that number is expected to double over the next few years. Approximately 11 bats per turbine die each year in Alberta and there’s a very strong risk the hoary bat and silver-haired bat populations will be unable to withstand the current rate of mortality.” Bats are killed when they fly directly into the turbines’ blades, but they also appear to be affected by the low-pressure system created by the turbines, which is suspected of causing damage to their lungs (barotrauma). There is a way to greatly reduce fatalities, but it requires a willingness on the part of wind farm operators to be flexible. Most mortalities occur at night, during fall migration, and at low wind speeds (when less energy is created). Turning off the turbines for these periods of time could make the difference between life and death.
Training for Pest Control Professionals
Rehousing bats, particularly large colonies, is very feasible and can meet the homeowners’ needs while also protecting the bats. A survey undertaken last year in Alberta and Saskatchewan, however, showed that current practices and training for pest control professionals are highly variable. Efforts are currently underway to create a standardized set of recommendations and an online training program for pest control professionals. Cory says they hope to establish partnerships and outline the training plan this year and start filming and developing content for the training platform next year.
Alberta contributes data to the North American Bat Monitoring Program, a collaborative bat monitoring program made up of an extensive community of partners across the continent who use standardized protocols to gather data that can be used to assess population status and trends, inform responses to stressors, and sustain viable populations.
Bat Education and Research Organizations in Western Canada
Alberta Community Bat Program, Wildlife Conservation Society Canada
Western Canada Bat Conservation Program, Wildlife Conservation Society Canada
Neighbourhood Bat Watch (Manitoba, Ontario, Quebec)
BatCaver Program, Wildlife Conservation Society Canada
Canada Bat Box Program, WCS/Canadian Wildlife Federation
Photo credit: https://www.flickr.com/photos/apmckinlay/14210742732/