HAT prepares colony of Dark Night volunteers for the Second Annual Bat Count
- Created: Tuesday, 09 August 2016 17:13
PLUS Townsend’s Big-eared Bats Rescued in the Westshore
By Paige Erickson-McGee
From horror movies to health warnings, societal attitudes about bats are typically negative. Many people view bats as pests. This type of public attitude has contributed to the general decline of bat populations around the world to the point where over half the species found in the province are considered at risk.
There is fear about bats and rabies; they are the only mammal on Vancouver Island that is known to carry rabies, but we are looking at less than half a percent of bats testing positive for rabies in healthy populations. It is extremely rare, although it is an important reason never to handle bats, live or dead, with your bare hands.
There are 10 species that we know of on Vancouver Island, but there is much still to learn. Right now we have very little idea of where bats are roosting in the Capital Region, and we have almost no idea where some species hibernate in the winter time, whether they gather in small groups under protected spaces like firewood piles, or in big congregations in caves as seen in other parts of BC.
It is difficult to protect our bats when we do not know where they are roosting or how many there are. This also makes it a challenge to notice substantial population declines from disease. To address this concern, Habitat Acquisition Trust has prepared a colony of Dark Night volunteers for the Annual Bat Count across the Capital Region as a part of the BC Community Bat Program of Southern Vancouver Island. Similar to the bird or butterfly counts, this citizen-science initiative encourages residents to count bats at local roost sites.
The Annual Bat Count continues to help the BC Ministry of Environment collect baseline data on bat populations, specifically where they are roosting in the summer months looking at the density and distribution of roosts. The goal is to gain a sense of the bat population numbers before the devastating White Nose Syndrome (WNS) fungal disease affects bats in the province. WNS is caused by a fungus that usually affects the bats in caves during winter hibernation and is detectable in dead or dying bats found in the winter and spring until about May 1st.
“White Nose Syndrome is estimated to have killed more than six million bats since it was first discovered in eastern North America a decade ago,” says biologist Dr. Purnima Govindarajulu with the Ministry of Environment. “In March 2016, the disease was detected just east of Seattle. This has greatly increased our urgency to understand bat populations in BC. We need the public’s help to census local bat populations. The summer of 2016 may be our last year to obtain population estimates before White Nose Syndrome causes widespread declines in western North America.”
The National Wildlife Health Center issued a bulletin on July 15 2016 that stated a single Silver-haired Bat (Lasionycteris noctivagans) tested positive for the fungus, Pseudogymnoascus destructans (Pd). This bat was originally collected during the same month and in the same county as the Washington Little Brown Myotis bat (Myotis lucifugus) with previously confirmed WNS. This suggests that Silver-haired Bats may be a carrier of the fungal pathogen. Through the BC Community Bat Program, 31 bats from BC were submitted for fungal testing, and none tested positive for WNS.
The risk continues next winter so it is extremely important for landowners who have bats to count their colonies; we suspect large and important roosts are out there and we would like to help landowners conduct counts and protect the bats. We hope to prevent situations where people might unintentionally disturb or harm them.
What you can do:
• Protect wetlands on your land and in your neighbourhood, they provide key habitat for the bat’s food source
• Retain any standing dead trees or snags on your property (that are not a safety hazard) as they provide natural roosting habitat for bats
• Build a bat box with plans from www.bcbats.ca and follow instructions to install it in an appropriate location
• Ask your friends and neighbours if they have bats and if they do, direct them to HAT
• Participate in the Annual BC Bat Count in the summer months June 1 to 21 and July 21 to August 15, visit www.bcbats.ca for more information
Good News Stories – Big-eared Bats find a helping hand
On Saturday July 16, a partnership with Christina Carrieres from SPCA Wild Arc and Jeff Krieger from Alternative Wildlife Solutions sprang into action after HAT received a report of dead and live bats found in a Westshore building. Upon arrival, a total of 14 Townsend's Big-eared Bats (Corynorhinus townsendii) were rescued after becoming trapped in the interior of a building – several were emaciated and dehydrated. Of the 14 that were collected, 4 were adult females still feeding their pups, and the other 10 were pups themselves, 3 of which did not survive the journey to the rescue centre.
The 11 surviving bats were rehydrated and fed mealworms over two nights at the Wild ARC centre, and then re-released back into the roost with HAT staff on July 18. Very conscious of not disturbing any other bats inside the attic where more bats were roosting, Christina carefully placed each bat back at the entrance of the roost, and one by one the bats crawled back in. Christina described the Townsend’s species as being much gentler and more docile than the Myotis species she is more familiar with.
The building has since been appropriately repaired to ensure the bats cannot become trapped in the interior, but HAT is continuing to work with the property managers to ensure this roost remains protected and continues to provide habitat for the bats. It appears there is a significant colony of Townsend’s Big-eared Bats living in the attic of the building, and upon counting the bat roost on July 25, a total of 33 bats were observed.
This particular species of bat typically roosts in larger structures with slightly cooler temperatures than other species, and do not tend to use typical bat boxes. With the warm weather continuing, HAT staff have been working with the provincial bat biologists and Species at Risk specialists to identify how we can support this particular colony of bats, collecting options such as building a bat condo or another structure to provide additional roosting habitat on site.
According to the BC Ministry of Environment, “Townsend’s Big-eared Bats are at risk because they are confined to small regions of suitable habitat at low elevations in the southern part of British Columbia – precisely the areas that humans prefer to occupy. Disturbance of females with young can severely lower breeding success. Repeated disturbance at winter hibernacula can cause energy loss, abandonment of the caves and death.” The Townsend’s Big-eared Bat is currently listed on the Provincial Blue List.
This project is in need of funding and experienced volunteers to conduct site visits, manage many questions from the public, and for equipment. The project is partially funded by the Habitat Conservation Trust Foundation with support of the BC Conservation Foundation, and the Federal Habitat Stewardship Program. HAT provides information for people managing bats in buildings on their property or who have questions about how to steward and attract bats.
Photo Credits: Christina Carrieres, BC SPCA WildARC