What's for Dinner? The Diet of the Snowy Owl and Canada Lynx

Snowy Owl, Uri Goldman www.Arkive.org (1).

     The Snowy Owl is a nocturnal bird of prey characterized by it's white plumage. Males are nearly pure white, and females are mostly white with dark brown bars on their wings and backs (10).   They are about 60 cm. long on average, with wingspans of 1.3-1.5 m. (20). Females are larger than males, which is typical in raptor species (4). Hatchlings are born with white down, which quickly becomes sooty grey, developing into brown with white bars when they reach juvenile age. Lifespan in the wild is estimated at 10 years (20).

2-day old Snowy Owl hatchling, Chris Ketola courtesy of Ontario Specialized Species Centre (6).

Owls evolved 70-80 million years ago (21). Since then, species divergence has been occurring through diet specialization, migratory patterns, and physical adaptations (22). These events have led to the emergence of the owl species we know today, including the Snowy.

Snowy Owl Range, Dan Gleason (4).

The Snowy Owl lives in the northern tundra, in North America and the Eurasian continent. In North America, it lives year-round in northern Alaska, the Yukon, North-West Territories, Quebec, and Labrador. Living up North where the daylight period can reach 24 hours of darkness is advantageous for a nocturnal predator. Snowy's spend their winters scattered through southern Canada, Minnesota, New York, and sometimes even further south in California, Texas, and Nevada (8). Male Snowy Owls are nomads, while females are known to be territorial (3). During wintering migrations, young males will head south first, only to be later displaced when the larger adult females come and force them further south. A gradient can be seen during wintering season from North to South of large adult females, intermediate adult males and young females, and then young males being the furthest South (11). 

Canada Lynx, lightwave photography, www.Arkive.org (7).

The Canada Lynx is a medium-sized nocturnal feline characterized by it's black ear tufts, facial ruff, very large feet, and short, black-tipped tail. The males are roughly 15-25% larger than the females. They are 2 feet tall and around 2.5 to 3 feet long (2). Cats evolved from prehistoric ancestors roughly 25 million years ago (20). Like the owls, speciation occurred due to migratory patterns and physical adaptations associated with natural selection, eventually creating the feline species we know today, including the Canada Lynx (20). 

Canada Lynx Range, K. Jefferson, www.nhptv.org (5).

Canada Lynx like to live wherever they can find food: primarily snowshoe hares (12). They prefer to live in boreal regions, and are found in the northern limits of Alaska, Yukon, and mainland North West Territories (23). Lynx are found in forests over 20 years old undergoing regeneration. Lynx dens have been mostly found near windblown or fallen down trees in regenerating forest stands, and they also show strong preference for deep snow cover (22). Lynx are naturally reclusive animals, and they demonstrate social intolerance and mutual avoidance. Lynx increase home range size when there is a shortage in hares. Male and female territories often overlap, but same sex overlapping is rare (20).

Canada Lynx, Eric Bacceda, www.Arkive.org (7).

 Natal dens are most often found between coniferous trees (16). Breeding season begins in late winter and continues into early spring. Kits are born in litters of 2-4 after a 54 day gestation period. They weigh 200-300 grams at birth and can begin eating meat at 1 month of age (16). Males do not participate in raising the kits. The young will remain with their mother until the following breeding season, when they will then separate (22). The lifespan for the lynx is 10-20 years (16).