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Sage – grouse once numbered as high as 16 million across the western United States, but the bird’s populations have plummeted in recent decades. The Trump administration plans to open up drilling on 9m acres of public land in the west, which are the habitat for thegreater sage grouse, a bird known for its mating dance and is considered an “ umbrella species” – a bellwether for the health of many other species. Here we look at some of the animals most at risk from Trump’s rollbacks. It has shrunk several national monuments and opened up a huge amount of federal land for oil and gas drilling, coalmining and other industrial activities – actions that conservationists warn could imperil species whose numbers are already dwindling and that are core to the health of our ecosystems. The United States is the ninth most at risk.ĭespite this desperate outlook, the Trump administration, as part of its aggressive rollback of regulations designed to protect the environment, has lifted protections for America’s animals. According to a sobering report released by the United Nations last year, 1 million land and marine species across the globe are threatened with extinction – more than at any other period in human history.Īccording to a recent study, about 20% of the countries in the world risk ecosystem collapse due to the destruction of wildlife and their habitats, a result of human activity in tandem with a warming climate.
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Although polar bears can adapt their diet to include sea bird eggs and caribou when on land, a 2015 study published in the journal Frontiers in Ecology and the Environment found that the calories they gain from these sources do not balance out those they burn from foraging for them, Live Science previously reported.T he prognosis for biodiversity on Earth is grim. That represents the loss of an area about twice the size of California. "It's why what we're seeing now - all of these starving polar bears trying to find alternative food sources - could really represent a tipping point."Īccording to a statement from the National Snow and Ice Data Center (NSIDC), Arctic sea ice, which the bears use as their hunting grounds, decreased by about 336,000 square miles (870,000 square kilometres) this year from its 1981 to 2010 average maximum. Their diets haven't changed much at all." DeSantis said, referring to blubbery meals such as seals. "Polar bears consumed soft foods even during the Medieval Warm Period, a previous period of rapid warming. (Image credit: Kt Miller/Polar Bears International)Īccording to DeSantis, generalist animals such as coyotes and cougars are the best survivors of rapid change to their environment, not highly specialized apex predators like polar bears and saber-toothed cats. This precipitous fall is linked partly to the encroachment of grizzly bears into polar bear ranges, where they outcompete them for alternative food sources, but also to polar bears' highly specialised diets, as DeSantis highlights in research published on April 1 in the journal Global Change Biology.Ī polar bear and its cub in the arctic. The rise of the pizzlies coincides with polar bears’ decline: their numbers are projected to decrease by more than 30% in the next 30 years, according to a 2016 study in the journal Biology Letters. Since then, sightings of the hybrids have been increasing, with a 2017 study in the journal Arctic showing eight hybrids springing from a single female polar bear who mated with two grizzly bears. DNA tests confirmed that the animal was a hybrid - the first documented wild offspring of a polar bear and a grizzly bear. When he took a closer look he found an altogether more unusual animal: A bear with the cream-white fur of a polar bear but the long claws, humped back, shallow face and brown patches of a grizzly. Wild sightings of hybrid pizzly bears began in 2006, when a hunter shot what he thought was a polar bear in the Northwest Territories of the Canadian Arctic. Observations made in captivity and a study conducted in the wild also suggest that the hybrids are fertile and have themselves produced young. Grizzly bears and polar bears only diverged 500,000 to 600,000 years ago, so the two species can mate and produce viable offspring.