Alaska Fauna. Photo Album. 2020. Romans Arzjancevs
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Название: Alaska Fauna. Photo Album. 2020
Автор: Romans Arzjancevs
Издательство: Издательские решения
Жанр: Биология
isbn: 9785005148087
isbn:
Editor Romans Arzjancevs
ISBN 978-5-0051-4808-7
Created with Ridero smart publishing system
ARCTIC FOX
– The Arctic fox preys on many small creatures such as lemmings, voles, ringed seal pups, fish, waterfowl, and seabirds. It also eats carrion, berries, seaweed, and insects and other small invertebrates.
– Arctic foxes must endure a temperature difference of up to 90—100° C between the external environment and their internal core temperature. To prevent heat loss, the Arctic fox curls up tightly tucking its legs and head under its body and behind its furry tail.
– The Arctic fox lives in some of the most frigid extremes on the planet, but they do not start to shiver until the temperature drops to —70° C. Among its adaptations for survival in the cold is its dense, multilayered pelage, which provides excellent insulation. Additionally, the Arctic fox is the only canid whose foot pads are covered in fur. There are two genetically distinct coat color morphs: white and blue.
RED FOX
– Red foxes colonised the North American continent in two waves: during or before the Illinoian glaciation, and during the Wisconsinan glaciation. Gene mapping demonstrates that red foxes in North America have been isolated from their Old World counterparts for over 400,000 years, thus raising the possibility that speciation has occurred, and that the previous binomial name of Vulpes fulva may be valid.
– Red foxes typically dominate other fox species. Arctic foxes generally escape competition from red foxes by living farther north, where food is too scarce to support the larger-bodied red species. Although the red species’ northern limit is linked to the availability of food, the Arctic species’ southern range is limited by the presence of the former. Red and Arctic foxes were both introduced to almost every island from the Aleutian Islands to the Alexander Archipelago during the 1830s—1930s by fur companies.
– Red foxes prefer to hunt in the early morning hours before sunrise and late evening. Although they typically forage alone, they may aggregate in resource-rich environments. When hunting mouse-like prey, they first pinpoint their prey’s location by sound, then leap, sailing high above their quarry, steering in mid-air with their tails, before landing on target up to 5 metres away. They typically only feed on carrion in the late evening hours and at night.
COYOTE
– Coyotes walk around 5—16 kilometres per day, often along trails such as logging roads and paths; they may use iced-over rivers as travel routes in winter. They are often crepuscular, being more active around evening and the beginning of the night than during the day. Like many canids, coyotes are competent swimmers, reported to be able to travel at least 0.8 kilometres across water.
– The coyote is ecologically the North American equivalent of the Eurasian golden jackal. Likewise, the coyote is highly versatile in its choice of food, but is primarily carnivorous, with 90% of its diet consisting of meat.
– Coyotes rarely kill healthy adult red foxes, and have been observed to feed or den alongside them, though they often kill foxes caught in traps. Coyotes may kill fox kits, but this is not a major source of mortality.
GRAY WOLF
– In Southeast Alaska, Sitka blacktailed deer, mountain goats, and beaver are the most important sources of food. Research indicates that salmon are important seasonally where they are available, especially to young wolves. During summer, small mammals including voles, lemmings and ground squirrels are taken. Wolves also scavenge, and coastal wolves will beach comb.
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