4/25/2023 0 Comments Polar bears predatorsThe drone pilot and observer were stationed on the roof of a research cabin and launched/landed the drone within an electrified fence surrounding the research station. Bears were filmed as soon as researchers noticed them on the island and bears were recorded until they either left the island or were resting for extended periods of time. We initiated filming when conditions were suitable for flying and when bears were actively foraging on eggs. We recorded foraging bears with drones (DJI Phantom 3 Pro and 4 Pro models, from July 10-20, 2017 between 0530 hrs and 2030 hrs. The foraging behaviours exhibited by polar bears in this study suggest they are inefficient predators of seabird eggs, particularly in the context of matching behaviours to resource density. ![]() Lastly, bears that capitalized on visual cues of flushing eider hens significantly increased the number of clutches they consumed however, they did not use this strategy consistently or universally. Bears did not display different movement modes related to nest density, but became less selective in their choice of clutches to consume. Bears visited fewer nests overall as the season progressed, but marginally increased their visitation to nests that were already empty. Using aerial-drones, we recorded multiple foraging bouts over eleven days, and found that as clutches were depleted to completion, bears did not exhibit foraging behaviours matched to resource density. We investigated bears’ foraging performance on common eider ( Somateria mollissima) eggs on Mitivik Island, Nunavut, Canada to test whether bear decision-making heuristics are consistent with expectations of optimal foraging theory. Given that polar bears have evolved to hunt seals on ice, they may not be efficient predators of seabird eggs. As a result, there have been increased reports of polar bears foraging on seabird eggs across parts of their range. Strong, sharp claws help the polar bear gain traction, dig through ice, and kill prey.Climate-mediated sea-ice loss is disrupting the foraging ecology of polar bears ( Ursus maritimus) across much of their range. Uneven skin on the soles of the feet helps to prevent slipping. The feet have hairy soles that protect and insulate as well as ease movement across ice. Under the skin is a layer of insulating fat. Polar bears have thick fur and black skin, which absorbs the heat from the sun. The short tail is only 3–5 inches (7–12 centimeters) long. It grows to about 5.3 feet (1.6 meters) tall at the shoulder and can reach 8 feet (2.5 meters) in length. The male is much larger than the female and weighs 900 to 1,600 pounds (410 to 720 kilograms). Polar bears have a long neck, a relatively small head, and short rounded ears. ![]() ![]() ![]() The polar bear’s scientific name is Ursus maritimus. It has no natural predators and does not fear humans, making it an extremely dangerous animal. Except for one subspecies of brown (grizzly) bear, the polar bear is the largest and most powerful carnivore (meat eater) on land. The polar bear travels long distances over vast desolate spaces-mostly drifting on floating ice in the ocean-in its search for seals, its primary food source. The great white northern bear that is found throughout the Arctic region is the polar bear. Contunico © ZDF Enterprises GmbH, Mainz Thumbnail © Uryadnikov Sergey/
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