Research Group on Introduced Species (RGIS) —
White-nose Syndrome (WNS) was introduced into North America in 2006. It is a fungal disease which grows on hibernating bats, forcing them to wake from their slumber to groom the fungus from their face and wings. Ultimately, these bats die of starvation from waking too many times during their long winter sleep. Until recently, the fungus did not occur west of Ontario. But just a few weeks ago, a bat in Washington state just west of Seattle was confirmed to have died from WNS. Because WNS has caused catastrophic mortality in eastern bat populations – now estimated to have killed over 6 million bats – this is of great concern to bat populations coast to coast.
While the sudden jump to the West Coast puts bats at risk, Haida Gwaii may prove to be a refuge from the disease due to its remote location and relative low frequency of bats moving between the islands and the mainland. The fungus that causes White-nose Syndrome is often unwittingly spread by humans – especially those that enter caves or handle bats in infected areas.
Bats comprise 40% of the native mammal species that are resident on Haida Gwaii, and they are very important to our ecology. Bats are our primary nighttime insect predators, and can eat up to half of their body weight in insects in one night. They control many pest species, such as mosquitos.
There are four main actions that people can take to help in managing the risk of WNS on Haida Gwaii:
- Do not enter caves on Haida Gwaii for any reason
- Report bat roosts (natural or in buildings) with multiple bats.
- Report any sightings of bats during winter months.
- Collect any dead bats (wear gloves and bag the carcass) for disease testing.
Increased surveillance by the public is also key in tracking the presence or spread of the disease. Unlike the bats of eastern North America, western bats are not known to inhabit large hibernacula, but rather may roost in small numbers in dispersed locations such as rocky crevices or large trees. Because of the small size of colonies in western Canada, few roosts are known, and public reports are the most effective way of gathering information on roost sites. Increased numbers of bats flying in the winter may be a sign of WNS.
When collecting dead bats, keep in mind that the fungus does not pose a risk to humans, but there is always a small risk of rabies – so please wear gloves while collecting bats and avoid touching the bat directly. Please contact Berry Wijdeven, Species at Risk Biologist (250-559-6245), Lucy Stefanyk, BC Parks (250-557-4390) or Stu Crawford, CHN (250-626-3302) so that we can collect the bat for disease testing. Bats that are still alive should not be disturbed, but reported immediately. Please report all sightings of bats between November and March to Carita Bergman at the Parks Canada office in Skidegate (250-559-6313)
Lastly, if you know of bats inhabiting buildings, there are a number of good stewardship techniques one can employ to ensure a healthy bat population. These sites may also provide locations for sampling for the fungus that causes WNS, a procedure that can be accomplished quickly with the appropriate swab kit. Contact any of those listed above for more info.