Bat Monthly Chauves-souris Mensuelles September 2019
Featured story
BC Annual Bat Count
Mandy Kellner, BC Community Bat Program Provincial Coordinator
bcbats@gmail.com
The BC Annual Bat Count is one component of the BC Community Bat Program. It is a summer emergence count of bats at day roosts in human-made structures (e.g. houses, barns, bat houses). Ideally, bat counts occur four times each summer at each site – two pre-pup surveys in June followed by two post-pup surveys in July and August when pup are flying. You can find more detailed protocols and reports on our website www.bcbats.ca .
The BC Annual Bat Count has been valuable for promoting stewardship of roosts by private landowners, and offers an opportunity for community outreach and involvement, as we always need help to count bats at larger roost sites. The BC Annual Bat Count is promoted, organized, and sometimes conducted by regional coordinators, but remains largely a citizen-science, volunteer-based effort. In 2018 alone, volunteers donated 613 volunteer-nights, participating in 540 bat counts. One of the challenges faced by the program is retaining these roost stewards and volunteers through a multi-year project. The involvement of regional coordinators likely helps by building local connections with participants; we are also working on increasing feedback to roost stewards and volunteers.
Since the program was initiated in 2012, as of 2018 we have data on seven bat species from 2,107 counts done at 389 sites around the province. The resulting dataset is valuable as part of the BC provincial bat monitoring program. Individual sites can be monitored for rapid declines, which are expected with the imminent arrival of white-nose syndrome in BC. On a larger scale, our growing data set will be used to look at trends regionally and provincially. It can potentially help monitor the spread of disease, identify differing impacts on different species, and document recovery. We are currently working to contribute the count data to the international NABat Monitoring Program, and continue to consider ways to partner with Batwatch.ca in Canada, to maximize the knowledge gained from all the time and effort generously put in to the BC Annual Bat Count. If you would like to find out more about the counts or our results, please get in touch at bcbats@gmail.com.
The BC Annual Bat Count and the BC Community Bat Program are funded by Habitat Conservation Trust Foundation, Forest Enhancement Society of BC, the Province of BC, private donors, and many regional funding sources.
Featured contributor
Dr. Christina Davy – Adjunct Professor, Trent University; Research Scientist (Species at Risk), Ontario Ministry of Natural Resources and Forestry
I lead a conservation ecology lab at Trent University (Peterborough, Ontario). My research group studies the effects of disease, landscape modification and anthropogenic sources of mortality on threatened wildlife populations (mostly bats and reptiles). My adventures with bats started with a Masters at Western University with Brock Fenton, who convinced me that bats are as wonderful as turtles. After a PhD with Bob Murphy at the Royal Ontario Museum I returned to bats through a contract with the Canadian Wildlife Service, a Liber Ero postdoctoral fellowship, and now my current position in Peterborough. My team spends most of the summer monitoring bat populations in southern Ontario with surveys of maternity and swarming sites. Lately we’ve also used MOTUS tags to understand how bats are moving across the landscape. We spend our winters impatiently waiting for the bats to emerge from hibernation, and analyzing our data to learn more about bat population structure and habitat use, particularly with respect to aerial habitats. We also explore the differences between bats that have survived WNS, and those that did not, using genomic and transcriptomic analyses. I am particularly excited about several recent genetics studies in which we explored the molecular responses of different species of bat to white-nose syndrome, and described signatures of immunogenetic selection for WNS survival in little brown bats. We are currently investigating the apparent recovery of some bat species Ontario post-WNS, using a range of field and genomic tools. Our work is possible thanks to a network of wonderful academic, government and eNGO collaborators in North America and Europe, including the Canadian Wildlife Health Cooperative*. I am grateful to my students and collaborators for a wild ride so far, and I look forward to more in the next few years.
*Fun fact: Jordi and CWHC Atlantic have been mailing me boxes of frozen bat feet** since 2014.
**from dead bats, of course…
White-nose syndrome surveillance
Bat-killing disease white-nose syndrome confirmed east of the Cascade Range in Washington
OLYMPIA – White-nose syndrome, an often-fatal disease of hibernating bats, has been confirmed for the first time in Washington east of the Cascade Range. Kittitas County is the fourth county in Washington affected by the disease or the causal fungus, joining King, Pierce, and Lewis counties.
Fighting a bat killer: B.C. scientists testing new way to protect against deadly fungus
More batty visitors in the N.W.T? Northerners on social media think so
Researchers trap and track bats in P.E.I. National Park
Penicillium diversity in Canadian bat caves, including a new species, P. speluncae
Yilmaz et al.
Penicillium species were commonly isolated during a fungal survey of bat hibernacula in New Brunswick and Quebec, Canada. Strains were isolated from arthropods, bats, rodents (i.e. the deer mouse Peromyscus maniculatus), their dung, and cave walls. Hundreds of fungal strains were recovered, of which Penicillium represented a major component of the community. Penicillium strains were grouped by colony characters on Blakeslee’s malt extract agar. DNA sequencing of the secondary identification marker, beta-tubulin, was done for representative strains from each group. In some cases, ITS and calmodulin were sequenced to confirm identifications. In total, 13 species were identified, while eight strains consistently resolved into a unique clade with P. discolor, P. echinulatum and P. solitum as its closest relatives. Penicillium speluncae is described using macro- and micromorphological characters, multigene phylogenies (including ITS, beta-tubulin, calmodulin and RNA polymerase II second largest subunit) and extrolite profiles. Major extrolites produced by the new species include cyclopenins, viridicatins, chaetoglobosins, and a microheterogenous series of cyclic and linear tetrapeptides.
Fungal Systematics and Evolution, https://doi.org/10.3114/fuse.
Site occupancy of little brown bats (Myotis lucifugus) in response to salvage logging in the boreal forest
Thomas et al.
As a consequence of warmer winters, the frequency and severity of bark beetle infestations has increased in western North America, creating controversy over how to manage beetle-killed forests. Post-infestation salvage logging is increasingly used to reduce wildfire risk and recover the value of beetle-killed trees; however, the ecological consequences of this practice are poorly understood. We investigated the effects of post-infestation salvage logging in the boreal forest (Yukon, Canada) on habitat use by the little brown bat (Myotis lucifugus), a forest-dwelling species that is relatively tolerant of vegetative clutter and numerically dominant in boreal bat communities. We hypothesized that little brown bats would select closed-canopied sites, particularly at high latitudes where bats may be vulnerable to predators during midsummer when daylight is nearly continuous. Thus, we expected low occupancy rates in salvage-logged stands, particularly those with low tree retention. Because night length increases drastically after summer solstice, we also predicted that bat preference for closed canopies would decline by late summer. We monitored for bat presence with ultrasound detectors in 30 unlogged, beetle-affected stands and 60 small (<30 ha) salvage-logged stands of variable retention. We used occupancy models to test predictions regarding bat response to logging and associated changes in forest structure at local and landscape scales. Contrary to our predictions, occupancy by little brown bats was generally higher in salvage-logged stands, although differences were not statistically significant. Bat occupancy declined with increasing tree basal area, particularly during the second half of the summer when bats avoided forest stands with basal area >40 m2/ha. Our results suggest that vegetative clutter was a primary constraint for little brown bats. The observed clutter avoidance in late summer may have been caused by the presence of newly volant juveniles, which are not yet proficient at flying in clutter. In addition, bats may have shifted their preference to open habitats during late summer when nights were longer and darker, and perceived predation risk was likely reduced. Our study suggests that small patches of salvage-logged boreal forest may improve foraging habitat for little brown bats through clutter reduction; however, we caution that interpretation of our results should be limited to the tree retention levels and scale of logging at our sites. Additionally, the potential importance of unlogged areas as roosting habitat requires consideration before prescriptions are made on the proportion of the landscape to be salvage-logged.
Forest Ecology and Management, 451, 117501, https://doi.org/10.1016/j.
Changes in underground roosting patterns to optimize energy conservation in hibernating bats
Ryan et al.
Non-migratory bats in colder climates use hibernation to survive winter. By reducing metabolic rate (i.e., using torpor), bats can survive winter on stored fat reserves. During hibernation, bats arouse from torpor and may move within the hibernaculum, a process called “internal migration”. We hypothesized that internal migration occurs to optimize hibernation energetics, in that bats move to select a microclimate to minimize energy expenditure both by seeking cooler areas of the hibernacula and avoiding those with large temperature fluctuations. Early in the winter we observed that 62% of bats were roosting in the warmer, less energy efficient, deepest 50 % of an abandoned mine hibernaculum. Late in the season there was a shift towards the cooler entrance area, thereby decreasing energy demands during the torpid period, with 78% of bats in the mine roosting within 50m of the entrance. Although there was no significant effect of hibernation period (i.e., early vs late winter) on the number of bats in huddles, the largest huddles occurred close to the entrance in late winter. To fully understand and manage bat populations it is important to understand that hibernation is a dynamic process with bats moving and interacting with one-another throughout the season.
Canadian Journal of Zoology, https://doi.org/10.1139/cjz-
Different management strategies are optimal for combating disease in East Texas cave versus culvert hibernating bat populations
Bernard et al.
Management decisions for species impacted by emerging infectious diseases are challenging when there are uncertainties in the effectiveness of management actions. Wildlife managers must balance trade-offs between mitigating the effects of the disease and the associated consequences on other aspects of the managed system. An example of this challenge is exemplified in the response to white-nose syndrome (WNS), a disease of hibernating bats. The fungal pathogen that causes WNS, Pseudogymnoascus destructans, continues to spread throughout North America. Texas, recently confirmed positive for the fungus, has documented 33 bat species in the state, with nearly half of those species naïve to the pathogen. We explicitly incorporated multiple management objectives, uncertainty, and risk in the Texas Parks and Wildlife Department decision to manage East Texas populations of the tri-colored bat (Perimyotis subflavus), a species highly susceptible to WNS. Alternatives included individual actions that act against P. destructans or benefit bats, a no active management option, and combinations of actions. Although our main objective was to identify WNS mitigation measures for tri-colored bats in culverts, we also considered the transferability of the decision for natural caves. In this scenario, the optimal decision differed for culverts and caves, with a “portfolio” combination of actions ranking as the best alternative for culverts and a single vaccine alternative for caves. Because the top management alternatives differed markedly between these two systems, finding treatments that have broad application is likely infeasible, given that each management decision is characterized by different mixtures of competing objectives.
North American Bat Monitoring Program regional protocol for surveying with stationary deployments of echolocation recording devices Rodriguez et al. 2019. Narrative Version 1.0, Pacific Northwestern US. Natural Resource Report. NPS/UCBN/NRR—2019/1975. National Park Service. Fort Collins, Colorado.
October 24-31, 2019
Bat Week is an annual, international celebration of the role of bats in nature. Bat Week is organized by a team of representatives from across the United States and Canada from conservation organizations and government departments.
