Bats in BC play significant roles in pest management and pollination. Bats can reduce the need for chemical pesticides and indicate ecosystem health by revealing insect population density. Because many insect populations are declining in BC due to agricultural and pollutant stresses, bats have been negatively impacted. One-half of BC bats are considered species at risk including Townsend’s big-eared bat, Corynorhinus townsendii; bats are protected under the Wildlife Act but this protection does not necessarily extend to their habitat or food sources.
BC bats are insectivores, meaning they feed exclusively on insects. They provide efficient pest management for many night flying insects, including the notorious mosquito, which reduces the need for chemical pesticides. Not only can this be an economic benefit, but the reduction of chemical pesticide use promotes native pollinator populations and reduces pollution of watersheds. Native pollinators continuously benefit agriculture; they have been nicknamed ‘farmer allies,’ and this name could also be extended to bats for their pest control.
Many climate researchers, including David Suzuki, have noted that insect populations are in decline. Unfortunately, that decline includes needed insects like pollinators as well as pests. Insects can be hard to directly observe and so this decline may go unnoticed. However, insect population decline directly impacts the health of bat populations as their foraging becomes more difficult. When bat populations suffer it may point to insect population decline, which may, in turn, reveal otherwise unnoticed aspects of ecosystem health. The effect of chemical pesticides is just one possible impact. Development, deforestation, and other kinds of pollution also impact insect life. This may lead to the question: if insect populations are in decline anyway, do we need to promote bat populations? Simply put, some insect species are in decline but that decline is not occurring at an even rate in every ecosystem for every species. Just
Vanessa Craig. Townsend’s Big-Eared Bat.
ask anyone living near stagnant water where mosquitos breed. Bats are sensitive to habitat disruption because they require hibernation habitat in winter, maternity roosts and habitat in spring and summer, and foraging habitat. Foraging habitat is often found in woodlands and wetlands due to insect activity. Unfortunately, woodlands and wetlands are often under development pressure, experiencing deforestation and drainage. It is possible to promote bat habitat by building bat houses and leaving dead trees standing for wildlife to roost, but development pressures continue to impact food sources.
Torrey Archer. Wetland, Clearwater, BC.
Bat populations have also been impacted by White Nose Syndrome, a fungus that kills millions of little brown bats throughout eastern Canada and the US. Bats are impacted by the fungus during hibernation. Because bats hibernate in dense colonies, the fungus quickly spreads, wiping out entire populations, particularly in caves. Bats in BC have not yet experienced White Nose Syndrome but its virulence makes this fungus a serious concern. For this reason, hikers should take care to clean their equipment well when cave hiking so as to avoid spreading the fungus. In Karst caves in BC and especially on Vancouver Island, care should be taken not only to avoid transmitting the Syndrome but also avoid disturbing bat colonies using the caves to roost.
TLC is committed to preserving the habitat of bats and many of TLC’s conservation covenants and properties have bat populations including Fort Shepherd, Pender Island, and Max Lake. TLC is also dedicated to conserving wetland habitats which contribute to bat food sources. Clearwater wetlands conservation has been a major project and fundraising goal over the last several months. This significant ecosystem supports an extensive amount of biodiversity, of which insects may not be the most glamourous but are nonetheless important, and is very close to becoming a fully protected site. Conservation covenants and acquisition where possible and appropriate are TLC’s means of protecting vulnerable ecosystems and endangered species across the province.
Bats get a bad rep oftentimes, but they contribute more than they disturb. They are part of a vast, interconnected system of natural pest management and pollination, as well as being bio-indicators of ecosystem change. Although they should be treated with the same care and caution extended to all wild things, bats deserve some love. Building bat houses and preventing development on wetlands and woodlands can support BC bat populations. Are there bats on your property? You could put a covenant on it to protect the habitat now and in the future. Learn more.
Dr. Merlin Tuttle. Townsend’s Big-Eared Bat.
Example of a constructed bat house to encourage roosting.
Wildlife snag on Sydney Island. A snag is a dead tree left standing which provides habitat.
Rae Costain
Guest Editor
