Title | Owl responses to habitat change at the landscape and regional scale and effects of weather in east central Alberta |
Publication Type | Thesis |
Year of Publication | 2003 |
Authors | Grossman, S. R. |
Volume | Biological Sciences |
Issue | M. Sc. |
Pagination | 95 |
Place Published | University of Alberta |
Publication Language | en |
Keywords | Aves, barred owls, Great horned owls, northern saw-whet owls |
Abstract | The purpose of this study is to determine the large-scale responses of owl species to 1 changes in habitat availability and configuration. I studied the relative effects of forest configuration and amount of forest on owl presence and abundance at the landscape scale (3 x 5km) in east central Alberta. I also examined the effects of regions (120 x 105km) on owl populations. Weather conditions that might affect owl detections were also examined. Responses of Great Horned Owls, Northern Saw-whet Owls, and Barred Owls to differences in forest configuration and amount were variable across regions, and the effects of regional differences were very strong. Habitat amount was more important than any combination of configuration variables for all three species, though in some cases the support for this conclusion was not very strong. Threshold responses to forest amount were only apparent for the Great Horned Owl, which increased in abundance from 0% to 60% forest cover, beyond this threshold their abundance dropped. Weather and timing variables affected detection of both Great Horned Owls and Northern Saw-whet Owls. Great Horned Owls were more likely to be detected at warmer temperatures, lower wind speeds, and later in the evening. Northern Saw-whet Owls were more likely to be detected in high forest cover, low temperatures, earlier in the season, and when both temperature and forest cover were high. In conclusion, owl abundance was more responsive to forest amount than configuration and it was clear that regional habitat characteristics were important for owls and need further study. |
URL | http://search.proquest.com/docview/305263850 |
Topics | Biology |
Locational Keywords | Lac La Biche, Meanook |
Active Link | |
Group | Science |
Citation Key | 44784 |