A MULTI-SCALE ANALYSIS OF NORTHERN GOSHAWK HABITAT IN ONTARIO

• Main Author: Bush, Peter G.
• Format: Text
• Language: unknown
• Published: Scholarship@Western 2006
• Subjects: Accipiter gentilis; northern goshawk; landscape analysis; landscape ecology; multi-scale; habitat suitability model; biogeography; Ontario; Northern Goshawk
• Online Access: https://ir.lib.uwo.ca/digitizedtheses/4680; https://ir.lib.uwo.ca/context/digitizedtheses/article/8492/viewcontent/2024_03_19_Northern_goshawk_habitat_in_Ontario_OCR.pdf

The northern goshawk (Accipiter gentilis) has been identified as a potential indicator of sustainable forest management by a number of state and provincial jurisdictions across North America, including Ontario. However, little is known about northern goshawk habitat use in Ontario. This thesis examined northern goshawk habitat using a multi-scale approach. Within the study, goshawk habitat was examined from the nest-tree scale through to the multiple home ranges, and even at the provincial scale. Examination of the micro-scale nesting habitat use revealed that goshawks in central Ontario preferred to nest in a hardwood tree (specifically aspen), and more importantly in trees that were significantly larger than those in the immediate vicinity. Goshawks also selected certain forest-types and avoided others. The nesting areas were characterized as well-stocked with larger (sawlog) trees and fewer small (polewood) trees, a high canopy closure, and a low shrub and ground cover. Goshawk occupancy rates did not differ for those locations with partial timber harvesting and those without. I further examined habitat use at the landscape scale. The composition and configuration of habitat in this portion of the study was examined at 7 spatial scales and multiple forest habitat classifications (including habitat defined for 3 prey species and for northern goshawks). The cumulative effect of parti al-timber harvesting only started to have a negative influence on goshawk nest occupancy at the 50-ha spatial scale, and was most influential at the 170-ha scale. Examining these multiple scales helped identify a potential threshold for goshawk occupancy of harvesting not evident at the micro-scale. I evaluated two untested goshawk habitat suitability models (HSMs) for their ability to predict known goshawk nest locations. Revisions were as analyzed and new goshawk HSM for central Ontario was iii proposed. Goshawk habitat use in Southern Ontario was also examined because the fragmented nature of this forest region compared the ...