| Widespread dispersal of Borrelia burgdorferi-infected ticks collected from songbirds across Canada. | Abstract Millions of Lyme disease vector ticks are dispersed annually by songbirds across Canada, but often overlooked as the source of infection. For clarity on vector distribution, we sampled 481 ticks (12 species and 3 undetermined ticks) from 211 songbirds (42 species/subspecies) nationwide. Using PCR, 52 (29.5%) of 176 Ixodes ticks tested were positive for the Lyme disease spirochete, Borrelia burgdorferi s.l. Immature blacklegged ticks, Ixodes scapularis, collected from infested songbird ... | 2011 | 21864130 |
| use of observed wild bird activity on poultry farms and a literature review to target species as high priority for avian influenza testing in 2 regions of canada. | the risk of avian influenza outbreaks in poultry is partially dependent on the probability of contact between domestic poultry and wild birds shedding avian influenza (ai) virus. the major objective of this study was to document wild bird activity on poultry farms to determine which wild bird species should be targeted for ai surveillance in canada. we collected data in 2 major poultry producing regions of canada, southwestern ontario and the fraser valley of british columbia, on the relative ab ... | 0 | 22851777 |
| mammalian mesopredators on islands directly impact both terrestrial and marine communities. | medium-sized mammalian predators (i.e. mesopredators) on islands are known to have devastating effects on the abundance and diversity of terrestrial vertebrates. mesopredators are often highly omnivorous, and on islands, may have access not only to terrestrial prey, but to marine prey as well, though impacts of mammalian mesopredators on marine communities have rarely been considered. large apex predators are likely to be extirpated or absent on islands, implying a lack of top-down control of me ... | 2014 | 25234377 |
| northwestern song sparrow populations show genetic effects of sequential colonization. | two genetic consequences are often considered evidence of a founder effect: substantial loss in genetic diversity and rapid divergence between source and founder populations. single-step founder events have been studied for these effects, but with mixed results, causing continued controversy over the role of founder events in divergence. experiments of serial bottlenecks have shown losses of diversity, increased divergence, and rapid behavioural changes possibly leading to reproductive isolation ... | 2005 | 15813781 |
| fitness correlates of song repertoire size in free-living song sparrows (melospiza melodia). | models of sexual selection propose that exaggerated secondary sexual ornaments indicate a male's own fitness and the fitness of his offspring. these hypotheses have rarely been thoroughly tested in free-living individuals because overall fitness, as opposed to fitness components, is difficult to measure. we used 20 years of data from song sparrows (melospiza melodia) inhabiting mandarte island, british columbia, canada, to test whether a male's song repertoire size, a secondary sexual trait, pre ... | 2005 | 15729661 |