New calculations indicate that land-based food sources like caribou, snow geese, and eggs might provide enough calories for bears to avoid starvation
From the AMERICAN MUSEUM OF NATURAL HISTORY
As climate change accelerates ice melt in the Arctic, polar bears may find caribou and snow geese replacing seals as an important food source, shows a recent study published in the journal PLOS ONE. The research, by Linda Gormezano and Robert Rockwell at the American Museum of Natural History, is based on new computations incorporating caloric energy from terrestrial food sources and indicates that the bears’ extended stays on land may not be as grim as previously suggested.
“Polar bears are opportunists and have been documented consuming various types and combinations of land-based food since the earliest natural history records,” said Rockwell, a research associate in the Museum’s Department of Ornithology who has been studying the Arctic ecology of the Western Hudson Bay for nearly 50 years. “Analysis of polar bear scats and first-hand observations have shown us that subadult polar bears, family groups, and even some adult males are already eating plants and animals during the ice-free period.”
Previous studies have predicted mass polar bear starvation by 2068, when annual ice breakup is expected to separate the bears from their sea-ice hunting grounds for a consecutive 180 days each year–creating ice-free seasons that will last two months longer than those in the 1980s. But those estimates assumed no energetic input from land food sources.
Gormezano and Rockwell computed the energy required to offset any increased starvation and then determined the caloric value of snow geese, their eggs, and caribou that live near the coast of the Western Hudson Bay. They found that there likely are more than enough calories available on land to feed hungry polar bears during the lengthening ice-free seasons.
Although the exact energetic cost for a bear to hunt geese and caribou is uncertain, polar bears in Manitoba have been reported ambushing caribou with the same energetically low-cost techniques they typically use to hunt seals. The similar size of these two prey species means that bears would need to hunt for caribou only as often as they would usually hunt for seals, the researchers say.
“If caribou herds continue to forage near the coast of Western Hudson Bay when bears come to shore earlier each year, they are likely to become a crucial component of the bears’ summertime diet,” Rockwell said.
The eggs of snow geese are another food source for bears, and the energetic cost of obtaining eggs in ground nests is exceedingly low, the researchers say. With adequate food sources available, snow geese are known to endure polar bear egg predation without detrimental effects to the population.
Scientific consensus holds that the rapidly melting circumpolar ice reserves will increasingly prevent polar bears from hunting the seals on which they currently depend. Nevertheless, these observations of one population along the Western Hudson Bay show that bears marooned on land might, where the conditions are right, stave off starvation by turning to alternate food sources.
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With Churchill, Manitoba population of polar bears surviving after the Hudson’s Bay ice goes out a month or more before the arctic ice and forms a month or more later, ordinary folk have known the bear would survive any serious reduction in ice in the arctic. This is one of those such self evident truths that it is sickening to see ‘scientists’ proclaim the obvious. Another obvious thing that these ‘experts’ didn’t consider is that if the arctic warms, then the forest encroaches on the shores and brings no end of creatures right to their doorstep. They can eat seals that have come ashore as I’ve clarioned for several years, their prey now a linear hunting ground instead of three dimensional. They could even live in the woods most of the time and eventually re-mate with grizzlies. Heck, I’m only a geologist and engineer, but I seem to have come across enough data to make myself a polar bear expert as a hobby.
That polar bears eat land resources has been known since the dawn of polar bear observation.
They have evolved specializations that help them prey upon ringed seals, other pinnipeds and marine mammals, but that doesn’t mean they can’t still eat the same things that their grizzly bear ancestors ate.
Bogus article,
Everyone knows that life is incapable of adapting to the constantly changing environments…
/s
Oh dear, it appears the Warmists will need a new standard bear(er).
Few biologist understand climate change, but many assume the propaganda to be true. their observations are then subject to confirmation bias. Climate changes! Adapt or face extinction. Polar bears seem to get this better than these biologists. Since most of the current interglacial was warmer than now, polar bears should be able to survive well into the next glacial period. And we will probably learn to like polar bear steaks cooked over a nice grill in our igloos above the frozen city of Chicago.
Just so I understand: If man kills baby seals, that’s a horrible thing, but if polar bears DON’T kill baby seals, that’s a horrible thing too. Now, if the polar bears are not killing enough seals for the environment, can we let the baby seal clubbing recommence to balance things out?
I would say humans are the most fortunate and we can influence our faith, but the animals have to adapt or they will have no other way. At least, we can try to do something…….
If the polar bears get really hungry. then they can always snack on a few of the Global Warming Tourists visiting the area in search of signs of melting ice,
Question
Year after year the summer temps in the Arctic do not vary significantly vs the average but the remainder of the year large variations that tend to be above the average. Any idea why?
Not a good case for global temp rise when the max temps are uniform.
Polar bears are flourishing.
Why? We’re no longer shooting them.
QED.
my prediction-If the arctic melts we wont need to protect polar bears at all. The seals will have to use the land as a base, so they will be easier to catch then ever. They use the shores sometimes now anyway, so it is a safe prediction. Polar bear numbers will soar now that finding food is much easier, just follow the coast until you find them. So in the end we will end up reinstating heavier levels of hunting to keep polar bears in check.