Description
White Kermode bears are not albinos as they still have pigmented skin and eyes.[1][4] Rather, a single, non-synonymous nucleotide substitution in the MC1R gene causes melanin to not be produced.[4] This mutant gene is recessive, so Kermode bears with two copies of this mutant, nonfunctional gene appear white, while bears with one copy or no copies appear black.[4] It is possible for two black bears to mate and produce a white cub if both of these black bears are heterozygous, carrying one copy of the mutant MC1R gene, and both mutant genes are inherited by the cub. Additional genetic studies found that white Kermode bears breed more with white Kermode bears, and black Kermode bears breed more with black Kermode bears, in a phenomenon known as positive assortative mating.[4] One hypothesis is that this happens because young bears imprint on their mother's fur colour.[3]
Kermode bears are omnivorous for most of the year, subsisting mainly on herbage and berries except during autumn salmon migrations, when they become obligate predators.[3] During the day, white bears are 35% more successful than black bears in capturing salmon.[9] Scientists have also found that salmon evade large, black models about twice as frequently as they evade large white models, giving white bears an advantage in salmon hunting. The white fur of the bear is harder to spot under water by fish than black fur is, so the bear can catch fish more easily.[9] On some islands, white Kermode bears have more marine derived nutrients in their fur, indicating that white Kermode bears eat more salmon than the black Kermode bears.[10]
Habitat
Fewer than 400 Kermode bears are estimated to exist in the coast area that stretches from Southeast Alaska southwards to the northern tip of Vancouver Island;[11] about 120 inhabit the large Princess and Prince Royal Island.[11] The largest concentration of the white bears inhabits 80-square-mile (210 km2) Gribbell Island, in the territory of the Gitgaʼata people.[12]
The bear's habitat was potentially under threat from the Enbridge Northern Gateway Pipelines, whose planned route would have passed near the Great Bear Rainforest.[13][14] Indigenous groups including the Gitgaʼat have opposed the pipeline.[15] The Enbridge Northern Gateway pipeline was rejected by the federal government in 2016.
Conservation
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The majority of the Kermode bears' protein intake is from salmon during the fall season.[9][16] Pipeline spills could cause damage to salmon populations by polluting ecosystems.[12] This would not only affect the bears but also the entire ecosystem, as salmon are a keystone species and are important to the nutrient intake of both aqueous and terrestrial environments.[17] The salmon contribute nutrients to water during spawning and contribute to the land with decomposition of their carcasses when predators, such as bears, scatter them throughout the forest.[17] Until November 26, 2016, the greatest pipeline threat to the Great Bear Rainforest had been the Enbridge Northern Gateway Pipelines, but Canadian Prime Minister Justin Trudeau shut the project down after the First Nations took the Canadian government to court and won.[18] Trudeau instead approved two different pipelines, the Kinder Morgan Trans Mountain Expansion Project and another Enbridge Pipeline, that have been deemed not to affect the British Columbia Coast or the Great Bear Rainforest.[18]
In 2012 the coastal First Nations banned trophy hunting of all bears in their territories of the Great Bear Rainforest; however, the British Columbia government did not do the same.[19] On November 30, 2017, after much public pressure to end the practice, the government of British Columbia banned the trophy hunting of grizzlies in the Great Bear Rainforest, but the hunting of black bears remains legal.[19] Black bears are the parent species of Kermode bears, and each one killed could be carrying the rare recessive gene that allows Kermode bears to be genetically produced; therefore, the continued hunting of black bears is a threat to the Kermode bear population.[19] Additional concerns in regards to hunting are caused by the understaffing of wildlife officers who enforce the hunting bans, as this could allow for poaching.[19] Grizzly bears also pose a threat to Kermode bear populations because of the decline of natural resources, especially salmon populations that are becoming subject to climate change and overfishing.[12][20] Using non-invasive hair-line traps scientists tracked the movement of grizzlies across the coasts and rainforest.[12] They found that grizzlies are moving into black bear and Kermode bear salmon feeding grounds more often. This disrupts the feeding of Kermode and other black bears, as they often retreat once grizzlies arrive.[12]
One of the most successful means of conservation for the spirit bears has come in the form of the Spirit Bear Lodge, a form of ecotourism. The lodge has stimulated the economy of the Klemtu Indian Reserve and has provided education and awareness about British Columbia bears.[19] The lodge provides visitors from all around the world the opportunity to participate in bear sightseeing.[19] Hunting brought challenges to the lodge, however, as bear carcasses were spotted and disturbed observers; hunting also makes the bears more cautious making it harder to spot them.[19] However, because the ecotourism has brought about much more economic and environmental benefit than hunting, ecotourism may prevail and cause a complete ban on bear trophy hunting in British Columbia.[19]
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