Observation: During a study to identify bat habitat (including potential hibernacula, maternity roosting, and foraging sites) in the Niagara River Gorge, a bat was observed on March 21, 2017 at a location that is atypical of a hibernation site during a time of year when bats would still be in hibernation. The bat, possibly a Little Brown Myotis though unconfirmed, was located under a rock ledge in a small rock crevice with no direct sun exposure (Appendix 1).
There are several hypotheses that come to mind which may explain this behavior:
White-nose syndrome: White-nose syndrome is a disease that affects hibernating bats, causing mass population declines. (Frick, Pollock, Hicks, Langwig, Turner, & Kunz, 2010). It is commonly known that White-nose syndrome (WNS) has decimated bat populations along the eastern seaboard of North America over the past 10 years. This has resulted in many bat species being newly classified as Species at Risk (SAR). Though WNS gets its name from the white fungus growing on the faces and wings of bats (www.whitenosesyndrome.org), bat can sometimes have the disease with out any sign of the fungus. Due to the elevation and size of the crevice that this bat was found in, the indication of white fungus was inconclusive.
Early Emergence: While the time of this observation would have been early compared to typical emergence from hibernation, it is possible that warmer temperatures played a factor in early emergence. However, this would still not account for the selection of this particular crevice. Bats typically select areas with some sun exposure due to their poor ability to thermo-regulate given their high surface to mass ratio. (Stones & Wiebers, 1965, p. 155)
In conducting a literature review on this unusual observation, a broader observation was realized. The lack of data available on the presence of bat species and bat population distributions in southern Ontario and more specifically, the Niagara region, is alarming. With the exception of several small micro-sites, very little data has been captured with respect to bat populations and habitat in Niagara. Due to declining populations there is an urgency to gather data to provide better understanding and informed data-driven decision making with respect to conservation of bat habitat.
It is believed that the fungus which causes WNS has its origins in Europe and was carried into North America through human activity. Evidence of the origin of this fungus and its migration to North America are a reminder of how easily human activity and a lack of environmental awareness can cause environmental disasters at a global scale.
References:
Frick, W. F., Pollock, J. F., Hicks, A. C., Langwig, K. E., Reynolds, D. S., Turner, G. G., … Kunz, T. H. (2010). An emerging disease causes regional population collapse of a common North American bat species. Science, 329(5992), 679-682. doi:10.1126/science.1188594
Stones, R. C., & Wiebers, J. E. (1965). A review of temperature regulation in bats (Chiroptera). American Midland Naturalist, 74(1), 155-last page?. doi:10.2307/2423129
White-nose Syndrome. (n.d.). What is white-nose syndrome? | white-nose syndrome. Retrieved from https://www.whitenosesyndrome.org/faq/what-white-nose-syndrome