A number of bat boxes will be placed in the park to help revive the once thriving little brown bat population that has been severely diminished over the last few years.
Below is the note that DASSP received, and the work will be done over the next few months;
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Urban Forestry has contracted the Toronto and Region Conservation Authority (TRCA) to increase bat habitat in Sam Smith Park. This project is anticipated to be completed in Summer/Fall 2022. I would also like to thank you for your tireless work advocating for the natural environment in Toronto. Please feel free to share this information with anyone who may be interested.
Background
Ontario’s resident bat species have suffered tremendous losses over the last decade – their declines are largely linked to White-nose Syndrome in addition to habitat loss, collisions with wind turbines and pesticide use. Within the Province of Ontario, four species of resident bats are currently considered species at risk (SAR), this includes the Little Brown Myotis, Northern Myotis, Eastern Small-footed Myotis and Tri-colored Bat – all of which are listed as endangered.
Little Brown Myotis, Northern Myotis and Tri-colored Bats are the most likely species to be encountered within the City of Toronto. All 3 species have been observed between 1999-2019 within the City of Toronto. Currently, capture or observation of these species can be challenging due to dramatically depressed populations and their cryptic nature.
Habitat loss is one cause of decline for these species that can be artificially augmented, the loss of forest cover and accessible anthropogenic roost locations (barns, attics, sheds) has increased with urban intensification. When natural or manmade resources are removed, absent or limited; artificial roost structures may contribute to population growth by providing suitable conditions to support maternity colonies of at risk bat species. Supporting and increasing the recruitment of juvenile bats into the breeding population is vital to maintaining and restoring our native bat populations.
Site Selection Rationale
All three species of at risk bats (Little Brown Myotis, Northern Myotis and Tri-colored Bat) likely to be found in the City of Toronto generally associate with forested cover for roosting and can be reliant on man-made structures such as buildings, or associated structures to support maternity roost sites. Maternity colonies of Little Brown Myotis primarily use buildings or other man-made structures as well as tree cavities, the spaces under loose bark or rock crevices. Northern Myotis are known to use similar, natural and artificial roost sites. Maternity roost sites for Tri-colored Bats are not as well understood and tend to associate with clusters of dead or living foliage, or the underside of overhangs on buildings or other artificial structures.
Factors that affect the productivity of bat box installations include sun exposure, proximity to a water source and open areas adjacent to forest cover which are productive for foraging. The attractiveness of a maternity roost site is largely dependent on temperature with hot, humid conditions (23.3° C to 34.4° C) being the most favorable. This is best achieved by placing boxes where they receive limited shading, particularly during morning hours. It is therefore advisable to place installations where southerly and/or easterly exposure is not heavily impaired by shading.
Placing several roosting features within close proximity allows bats to choose the most preferential location, day to day, based on the subtle differences at each location and how they interact with the weather, lighting and seasonal conditions. The more suitable roost options that exist, the more likely attractive roosting habitat will be available on any given day.
The proposed bat habitat installations are located to provide ideal maternity roosting sites. They offer easy access to forest, water sources and productive foraging grounds. They have relatively open surroundings but are in close proximity for forest edge. Relatively open, meadow habitat common through much of the southern portion of the park, combined with adjacent wetland and waterfront habitat should provide excellent foraging resources to support productive maternity roosts.
While tree-mounted boxes are often considered less favorable for a number of reasons, they provide conditions that may be beneficial under certain scenarios such as extreme summer heat. In addition, they may also be used by male bats and juvenile females that are not rearing young. These are often installed in pairs to provide a wider array of conditions at each location.
Proposed Work
The TRCA, contracted by the City of Toronto, will install 2 bat rocket boxes and 4 tree-mounted bat boxes. This would provide ample artificial roost sites to support a significant maternity colony.
The bat rocket boxes are four-sided, dual chamber boxes 45” in height. They are mounted on a 2-piece metal post which is set in a concrete footing. This creates an installation that is approximately 15’ high.
Tree-mounted bat boxes are installed at approximately 4-5m in height along a south or east facing forest edge or on a stand-alone tree. This reduces the amount of shading they receive, and allows them to be more easily discovered than if the boxes are installed inside forest cover. Placement of the tree mounted boxes on the island will reduce the likelihood of mammalian predation and close proximity to productive foraging sites.
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