Sentences with phrase «polar bear population estimates»

Large margins of error in polar bear population estimates means the conservation status threshold of a 30 % decline (real or predicted) used by the US Endangered Species Act and the IUCN Red List is probably not valid for this species.

Have a look at the details below and see if you come to the same decision I have: that it's not possible to compare WHB «core» area polar bear population estimates over time.

Is there a mutiny in the works between the IUCN Red List and the IUCN Polar Bear Specialist Group (PBSG) over polar bear population estimates or has there simply been a breach of ethics?

Not exact matches

Recent estimates suggest a 60 % reduction of the polar bear population by the year 2050.

Tagged breakup dates, Churchill, counting polar bears, Derocher, early breakup, estimates, Ontario, polar bear, population numbers, Wapusk National Park, western hudson bay

Tagged Amstrup, BBC, Carbon Brief, declining population, declining sea ice, Derocher, GWPF, IUCN Polar Bear Specialist Group, Kara Sea, media attention, PBSG, polar bears, population estimates, rapid response team, The Times, threatened, vulnerable, Webster

Tagged aerial survey, early breakup, endangered, invalid methods, later - than - average breakup, mark - recapture, polar bear, population estimate, Seth Stapleton, Southern Beaufort, Southern Hudson Bay, threatened, US Fish and Wildlife Service, Wapusk National Park, western hudson bay

At present, the global population of polar bears is estimated to be 22,000 to 31,000.

Note that both the IUCN PBSG (2014 update) and Environment Canada (2014 assessment) use a population estimate of 1030 for Western Hudson Bay polar bears (even PBSG 2013 assessment was «1000»).

Once you presuppose that climate change is happening, it doesn't take a leap of faith to incorporate the assumption into models to estimate the health of polar bear populations, the progress of glaciers, and the vulnerability of Arctic sea ice.

This is the 1st anniversary of Canada providing population estimates and trends independent of the pessimistic prognostications of the IUCN / SSC Polar Bear Specialist Group (PBSG)-- so let's celebrate the recent triumphs and resilience of polar bears to their ever - changing Arctic environment.

Polar bears are one of the most sensitive Arctic marine mammals to climate warming because they spend most of their lives on sea ice.35 Declining sea ice in northern Alaska is associated with smaller bears, probably because of less successful hunting of seals, which are themselves ice - dependent and so are projected to decline with diminishing ice and snow cover.36, 37,38,39 Although bears can give birth to cubs on sea ice, increasing numbers of female bears now come ashore in Alaska in the summer and fall40 and den on land.41 In Hudson Bay, Canada, the most studied population in the Arctic, sea ice is now absent for three weeks longer than just a few decades ago, resulting in less body fat, reduced survival of both the youngest and oldest bears, 42 and a population now estimated to be in decline43 and projected to be in jeopardy.44 Similar polar bear population declines are projected for the Beaufort Sea region.45

This is Fig. 8 from Lunn et al. (2013), the most recent report on the estimated size of the Western Hudson Bay polar bear population.

Tagged Amstrup, Derocher, estimates, global warming, polar bear, population decline, population numbers, predictions

If nothing is done to reverse possible scenarios outlined in the report, scientists warn that the global polar bear population — estimated at about 8,500 — could start to see significant trouble.

What «something» other than science might a polar bear scientist be tempted to use in estimating the polar bear population?

Tagged breakup, Churchill, climate change, East Greenland, global warming, grizzly, grizzly bears, habitat, Henrik Hansen, hybrids, Nunavut, polar bear, Polar Bears International, polarbearscience, population estimate, problem bears, radio, sea ice, sea ice declines, Wapusk National Park, western hudson bay, WWF