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In a systematic survey of habitat use by Haida Gwaii Saw-whet Owls during the breeding season, Gill and Cannings (1997) found that owls were detected more often at points closer to riparian areas and in habitats containing greater amounts of mature and old forest. They found that elevation, distance to saltwater and distance to a change in habitat type did not influence the likelihood of detecting an owl. As well, the condition of male owls in the breeding season appears to be appreciably lower when territories contain less mature and old forest. When the mature and old forest content within 500 m of a territory core falls below 60-70%, significant declines in calling rate, an indirect measure of condition, of the territory occupants have been noted (Holschuh 2004b, Holschuh and Otter submitted). Active owl sites were all found below 300 m elevation despite searches that included higher elevations. Active sites have been mostly in the CWHwh1 (submontane wet hypermaritime coastal western hemlock variant) and CWHvh2 (central very wet hypermaritime coastal western hemlock variant) biogeoclimatic zones. Although some owl sites have been located in the higher elevation CWHwh2 (montane wet hypermaritime coastal western hemlock variant), none have been detected in the mountain hemlock or alpine tundra biogeoclimatic zones on Haida Gwaii. Although survey logistics largely inhibit placing call playback surveys in these high-elevation habitats, calling owls at higher elevations would have been in earshot during numerous surveys conducted at lower elevations.
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