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"Snowy owl Behavior."
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Snowy owl invasion! : tracking an unusual migration
\"A historically large irruption of snowy owls during the winter of 2013-2014 brought them across the eastern US, and farther south than usual. Scientists used this opportunity to attach GPS tracking devices to some snowy owls to increase understanding of their winter behavior and migration.\"-- Provided by publisher.
Book
Predation pressure by avian predators suggests summer limitation of small-mammal populations in the Canadian Arctic
Predation has been suggested to be especially important in simple food webs and less productive ecosystems such as the arctic tundra, but very few data are available to evaluate this hypothesis. We examined the hypothesis that avian predators could drive the population dynamics of two cyclic lemming species in the Canadian Arctic. A dense and diverse suite of predatory birds, including the Snowy Owl (
Bubo scandiacus
), the Rough-legged Hawk (
Buteo lagopus
), and the Long-tailed Jaeger (
Stercorarius longicaudus
), inhabits the arctic tundra and prey on collared (
Dicrostonyx groenlandicus
) and brown (
Lemmus trimucronatus
) lemmings during the snow-free period. We evaluated the predation pressure exerted by these predators by combining their numerical (variation in breeding and fledgling numbers) and functional (variation in diet and daily consumption rates) responses to variations in lemming densities over the 2004-2010 period. Breeding density and number of fledglings produced by the three main avian predators increased sharply without delay in response to increasing lemming densities. The proportion of collared lemmings in the diet of those predators was high at low lemming density (both species) but decreased as lemming density increased. However, we found little evidence that their daily consumption rates vary in relation to changes in lemming density. Total consumption rate by avian predators initially increased more rapidly for collared lemming but eventually leveled off at a much higher value for brown lemmings, the most abundant species at our site. The combined daily predation rate of avian predators exceeded the maximum daily potential growth rates of both lemming species except at the highest recorded densities for brown lemmings. We thus show, for the first time, that predation pressure exerted without delay by avian predators can limit populations of coexisting lemming species during the snow-free period, and thus, that predation could play a role in the cyclic dynamic of these species in the tundra.
Journal Article
The snowy owl scientist
\"It's July on Alaska's North Slope, and scientist Denver Holt is in Utqiagvik surveying nests. Denver has been coming here since 1992, and the snowy owls he studies have been coming here much longer: thousands of years. With its mix of coastal, low-elevation tundra and a rich presence of lemmings, the North Slope is the only area in Alaska where snowy owls regularly nest. How do snowy owls decide where they will nest? How do they manage to arrive at locations where food will be abundant? What drives the success of these delicate tundra ecosystems? These are the mysteries Denver is trying to solve to help ensure a bright future for these elegant hunters.\" -- Amazon.com.
Book
The 2005 to 2006 Snowy Owl Irruption Migration to Western Montana
During the winter of 2005–2006, a large number of Snowy Owls (Bubo scandiacus) migrated to northwestern Montana. At least 42 owls were recorded in the Mission and Flathead Valleys. In one field of approximately 500 m2, 31 to 35 Snowy Owls roosted by day. Many owls roosted communally, and several age classes and both sexes were observed. No evidence of starvation or mortality was detected. This irruption migration was also noted throughout the Pacific Northwest.
Journal Article
Fight or flight
In December2008, off-duty Bureau of Environmental Criminal Investigations (BECI) Lieutenant John Matterà was photographing a snowy owl - a fairly uncommon visitor - at Jones Beach on Long Island when the unexpected happened.
Journal Article