Aeroconservation

In 2017, I laid out a framework for the identification of aerial habitats (30) in a collaboration with Drs. Adam Ford and Kevin Fraser. We proposed the term “aeroconservation” to parallel existing frameworks for terrestrial and aquatic conservation. We argued that without explicit recognition, aerial habitats cannot be adequately protected under international or national law (see here for application of these ideas to the New Zealand context).

Approximate flight heights for representative taxa, and proposed aerial habitat classification scheme for integration of aerial habitats into conservation policy and legislation (30)

Understanding threats faced by aerial wildlife is the first step towards effective protection. For example, we know that high-flying bat species such as hoary bats that migrate long distances face a range of threats, including collisions with man-made structures. But these species can be challenging to capture, so it is difficult to track their population sizes and determine if they are stable, increasing or declining. To obtain the first population trend estimates for long-distance migratory bats in Canada, we leveraged a large dataset of mortality data for bats at wind turbines in Ontario (57). Those data represents an enormous amount of survey effort by an array of ecological consultants, on behalf of wind energy companies that are working to mitigate their effects on bats. Thanks to their efforts we were able to estimate trends in bat abundance over time, and detect likely declines in abundance in four species of bat that are typically considered to be “common”. Based on our results we also proposed several hypotheses about how bats respond to aerial fragmentation.

We are now using the MOTUS Wildlife Tracking System to empirically test some of those hypotheses. Lauren Hooton and Dylan White are tracking the movements of bats migrating across the landscape to understand how they use aerial habitats during their regional migrations, and to test bats’ behavioural responses as new source of aerial fragmentation, such as wind turbines, are placed on the landscape. (Photo courtesy of Brock and Sherri Fenton).

Dylan White is using tiny GPS-altimeter devices to characterize hoary bat flight behaviour in three-dimensional space.

And Dr. Allie Anderson recently dug into Birds Canada’s wind-wildlife mortality dataset to test the effects of turbine design (tower height, rotor-swept zone, etc.) on bat and bird mortality.

In our 2017 paper on aeroconservation we proposed that classic landscape connectivity analyses could be applied to the airspace as well, to explicitly model connectivity of aerial habitats with respect to sources of habitat fragmentation or mortality risk. PhD student Alicia Korpach (co-supervised by Kevin Fraser, U Manitoba), is using tiny GPS transmitters to track the long-distance migrations of Eastern Whippoorwill (48). In the past two summers she has obtained ~7,000 location points for migrating Whippoorwill, and she is currently characterizing airscape connectivity with respect to artificial light at night (“light pollution”).

The airspace is habitat.