Why Canadian Developers Should Pay Attention to the Potential Uplisting of Migratory Bats

Ecologist installing a bat detector on a tree
Ecologist installing bat detector

By Julie Snow – Ecologist

I had the opportunity to participate in the 51st Annual North American Society for Bat Research Conference this year. Among the flurry of information and research being shared, one topic – the significant population declines of migratory bat species – was top of mind. Migratory bats include the Hoary Bat (Lasiurus cinereus), the Eastern Red Bat (Lasiurus borealis), and the Silver-haired Bat (Lasionycteris noctivagans). In this blog, we’ll explore what these population declines could mean for development projects both in Ontario and across Canada.


Ontario is home to eight species of bats. Of these, four are already designated as Endangered at either the federal or provincial level. In May 2023, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), posted a news release on their website indicating they had assessed the three migratory bats. Changes to the status of these species could ultimately lead to the need for increased conservation efforts and more stringent regulations to protect their habitats.

What’s Next?

At the federal level, once per year COSEWIC submits their assessments to the Minister of the Environment and Climate Change. The Minister then provides a public response statement (within 90 days). The response statement will provide critical insights to the next stages of the process including timelines for action. Following the Minister’s response statement, other reviewers will have at least nine months to determine if the species will receive protections under the federal Species at Risk Act (SARA 2002).

Currently we are just at the beginning of this process as COSEWIC submitted their annual report to the Minister on October 18, 2023.

The province of Ontario takes a similar approach. The Committee on the Status of Species at Risk in Ontario (COSSARO) will assess the migratory bats this November to determine their level of risk in the province. In my opinion, it’s quite possible these species will be assessed as Threatened or Endangered in Ontario, ultimately qualifying them for legal protection and recovery under the provincial Endangered Species Act (ESA 2007). Should this occur, any direct impacts to the species or their habitat in Ontario would require authorizations from the Ontario Ministry of Environment Conservation and Parks (MECP).

Watercolor rendering of bat in flight

Michael Durham Minden – Pictures little brown myotis in flight; adapted by Josh White (GEI)

The Impact on Development Projects

If these three species are listed as Threatened or Endangered by COSSARO, that would mean that 7 of the 8 bat species in Ontario and their habitat would be legally protected. For developers, this carries implications for ongoing and future projects and increases the likelihood of encountering a species at risk bat. This could mean you’ll need to conduct more comprehensive environmental impact assessments, implement additional mitigation measures, and adjust project timelines and budgets to accommodate the necessary permitting, authorization, and compensation efforts. For example, in Ontario it can take up to a year to achieve a permit that allows a development project to impact endangered species or their habitat. These types of permits also typically involve considerable compensation, such as habitat creation/restoration, and monitoring commitments to ensure that there is an overall benefit to the affected species.

These changes could impact which areas are deemed developable and the level of permitting effort or mitigative measures that need to be applied to projects. This topic is of critical interest to our team, and we’ll be monitoring for the government response. So stay tuned over the next 12-18 months to see if these changes will be implemented at the federal and/or provincial level.

Moving Forward Together

These changes to the status of migratory bats underscore the importance of innovation in project design and execution. By collaborating with experts, developers can navigate the evolving regulatory landscape and contribute to the preservation and recovery of species at risk and their habitats. Please contact me or visit our website to learn more.

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