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Abstract
The Northern Saw-whet Owl of the Queen Charlotte Islands, British Columbia is recognized as a distinct subspecies
Aegolius acadicus brooksi. Little is known of the biology of this subspecies, and no nests have ever been found. We surveyed for Northern Saw-whet Owls on the Queen Charlotte Islands between 4 May and 28 May, 1996 establishing 10 survey routes comprising a total of 238 survey stations on Graham and Moresby Islands. Routes were chosen to maximize coverage of different forest types. We detected 61 owls and identified five trees used by singing owls. No nests were found. We used discriminant function analysis to analyze general habitat variables collected at survey stations with or without owls in order to determine habitat preferences. Sites with owls were closer to riparian habitat and had more old forest (> 120 years old) and more young forest (10-30 years old) than sites without owls. Dominant tree species at sites did not have an effect on owl detections. Three trees used by singing owls were in old forest stands and two were in mature forest stands. These trees were larger in height and diameter, and had less shrub cover around them than randomly selected trees in similar aged forests.
Parent Publication
Citation
Gill, Michael; Cannings, Richard J. 1997. Habitat selection of Northern Saw-whet Owls (
Aegolius acadicus brooksi) on the Queen Charlotte Islands, British Columbia. In: Duncan, James R.; Johnson, David H.; Nicholls, Thomas H., eds. Biology and conservation of owls of the Northern Hemisphere: 2nd International symposium. Gen. Tech. Rep. NC-190. St. Paul, MN: U.S. Dept. of Agriculture, Forest Service, North Central Forest Experiment Station. 197-204.
