First Observations of an Eastern Screech-Owl, Megascops asio, Population in an Apple-Producing Region of Southern Quebec

Ngaiou L. Richards, Pierre Mineau, David M. Bird, Pierre Wery, Jacques Larivée, Jason Duffe

Abstract


Baseline information was collected on a local Eastern Screech-Owl population found in the apple-producing region of Saint-Hilaire and Rougemont, Quebec, as part of a larger study on pesticide exposure conducted between 2000 and 2003. Screech-Owls visited or occupied 41 of 89 nest boxes installed in 12 orchards and 2 control locations. The mean height of occupied nest boxes was 3.83 m (2.00 – 5.80 m). Squirrels, Sciurus and Tamiasciurius sp., and chipmunks, Tamias striatus, Northern Flickers, Colaptes auratus, and wasps were the owls’ primary competitors for the boxes. Intact Screech-Owl pellets retrieved from nest boxes (n = 82) had a mean length and width of 3.57 and 1.44 cm, respectively, and weighed a mean of 1.77 g. Screech-Owls in the study area consumed a variety of small mammal, avian, insect and aquatic prey. Of these, Meadow Voles, Microtus pennsylvanicus, were the predominant prey item identified in pellets, and Mourning Doves, Zenaida macroura, were the primary avian prey found in nest boxes. In Canada, the owl’s trend status remains largely unknown. The species is currently listed as “Not at Risk”, based on an assessment conducted for COSEWIC in 1986. Given that a limited amount of information exists on the natural history and ecology of the species in Quebec, we also generated a map of the owl’s distribution in the province, using data from ornithological databases and rehabilitation facilities. Potential risks to the species within the province, particularly pesticide exposure and habitat loss, are briefly addressed and follow-up studies are discussed.

Keywords


Eastern Screech-Owl; Megascops asio; natural history; ecology; apple orchard; Quebec; range; distribution; census; pellet analysis; prey inventory; nest box; wing chord; population management; pesticide exposure; habitat loss; development; conservation

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DOI: http://dx.doi.org/10.22621/cfn.v120i3.318



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