Acoustic Bat Survey at Hullett Provincial Wildlife Area

by Justin Johnson, Marsh Manager

Friends of Hullett conducted an acoustic survey in May 2025 to assess the bat diversity within the Hullett Provincial Wildlife Area. Using an Anabat Express bat detector, the primary objective was to identify the bat species inhabiting the marsh and effectively communicate their ecological significance to the public.

To achieve comprehensive spatial coverage, the Anabat Express unit was strategically moved across eight distinct locations and various land cover types within the marsh. The survey generated 10,466 initial acoustic “hits” after filtering by Insight Software. Subsequent in-depth analysis successfully identified 3,821 vocalizations to the species level, confirming the presence of four bat species; Big Brown Bat (Eptesicus fuscus): Comprising 78.77% of identified vocalizations; Little Brown Myotis (Myotis lucifugus): Accounting for 11.04% of identified vocalizations; Eastern Red Bat (Lasiurus borealis): Representing 6.77% of identified vocalizations and; Hoary Bat (Lasiurus cinereus): Making up 3.40% of identified vocalizations.

Spatial analysis of the data collected revealed a notable trend: bat vocalizations were more concentrated in remote areas, particularly above the Whistler Pool. In contrast, we observed the lowest detection rates in the highly-trafficked Sugarbush Parking Lot, suggesting a possible link between human disturbance and reduced bat activity.

The valuable insights gained from this survey will directly inform the optimal placement of 30 new bat boxes within Hullett Marsh. These bat boxes, constructed by students at F.E. Madill Secondary School in Wingham, Ontario, are part of a collaborative effort with Friends of Hullett. Through three educational sessions, Friends of Hullett taught students about threats to bat populations, their vital ecological role, the principles of acoustic monitoring (including a hands-on look at the Anabat Express unit), and local bat diversity.

The acoustic survey made possible by Titley’s Loan Program will ensure we deploy bat boxes effectively, thereby enhancing habitat availability and bolstering the local bat population within the Hullett Provincial Wildlife Area.