In the depleting density experiment it was found that the jays did respond to prey depletion and that the jays appear to use a hunting by expectation rule. These data suggest that the rule a predator uses depends on the distribution of prey.

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Because of the scarcity of information for bird communities at the major mainland rivers of southeastern Alaska, the main objective of this study was to provide baseline information including distribution, status, and habitat associations of breeding birds. I conducted a meta-analysis of all known reports (including the current study) conducted at major mainland rivers during the breeding season. I described bird species composition, distribution, abundance estimates, status, habitat associations, and guild membership for all birds recorded at 11 major mainland rivers. Based on incidental observations, 170 species were recorded by all studies. Of these, 134 species were known or suspected to breed, accounting for 50% of all birds known from Alaska and 80% of all birds known from southeastern Alaska. In addition, I provided information on species of management concern as well as management implications and recommendations. I used point counts to survey birds within deciduous riparian vegetation at 6 major mainland rivers during 2000-2002. I compared bird species composition, abundance, richness, and diversity among four main vegetation types of deciduous riparian vegetation: shrubland, young deciduous forest, mature deciduous forest, and mixed deciduous-coniferous forest. Species richness was similar among all habitat types; however, relative abundance and diversity of birds was highest in mixed forest stands. Mature forests had the greatest number of species associated with the Canadian interior. I also used point counts to compare bird species composition, abundance, richness, and diversity among 6 major mainland rivers consisting of three trans-mountain and three coastal rivers. Latitude, connectivity, and availability of mature and mixed forests were the major factors thought to cause differences in bird communities among rivers. Contrary to our predictions, coastal rivers had higher bird species richness, diversity, point abundance , and point richness than trans-mountain rivers. Of the 10 species associated with the Canadian interior recorded during point counts, 8 occurred at both trans-mountain and coastal rivers.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

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Urbanization is a worldwide trend resulting in loss of bird habitat, dominance of invasive species and higher densities of some predatory species. However, cities provide new opportunities for birds because of warmer winter climates and sources of artificial food. Proper management of urban habitat is significant for maintaining diverse bird communities and raising conservation awareness among city dwellers. This study aimed at identifying important urban bird habitats as well as their characteristics in Halifax Regional Municipality, Nova Scotia. Fourteen local birders outlined bird habitats on maps, and the information was compiled and presented using GIS. In total, 28% of the study area was indicated as key habitat for urban birds. By comparing the GIS data with existing conserved areas, coastal areas, marine habitat and urban wetlands were found to be under-represented in conserved areas. Following from the research findings, recommendations for improving habitat identification and management are made.