According to a recent study, polar bears are facing a disadvantageous diet due to climate change.

Due to the effects of climate change, Arctic polar bears are facing a reduction in sea ice and are now forced to rely on land for food during certain times of the summer. A recent study focused on polar bears in Hudson Bay aimed to determine if they are able to maintain their plump physiques, which are essential for survival. The results showed that despite their efforts to increase their weight, a large majority of polar bears are experiencing weight loss.

According to a study published in the journal Nature Communications, certain bears struggle to find food such as berries, eggs, sea birds, and caribou antlers. However, the effort and calories expended in their quest for sustenance often leads to weight loss and a net loss of energy.

According to Anthony Pagano, a wildlife biologist with the U.S. Geological Survey, some bears enter a period of semi-hibernation where they are not very active, but they still lose weight. This suggests that neither approach is effective.

The study observed the calorie intake, energy expenditure, and respiration of 20 bears in the wild. After three weeks, it was discovered that 19 of the bears lost an average of 47 pounds (21 kilograms), which is equivalent to about 7% of their body mass.

Polar bears attempt to maintain their weight during the summer following a spring season of abundant feasting and weight gain. According to researchers in the Hudson Bay region, the decrease in sea ice has resulted in polar bears spending three additional weeks on land compared to the 1980s, as noted by Pagano.

Polar bears typically consume fatty seals while located on sea ice, near the seals’ habitat. This is especially successful during the spring, as seal pups are transitioning from nursing and are easier targets for polar bears before they learn to swim and move away from the ice, according to Pagano.

In September of last year, the National Snow and Ice Data Center reported that the Arctic sea ice had reached its annual minimum, with approximately 1 million square miles (2.6 million square kilometers) less than in September of 1979. The United States Fish and Wildlife Service has designated polar bears as a threatened species due to the decline in their sea ice habitat.

According to biologist Andrew Derocher from the University of Alberta, this study demonstrates that polar bears are unable to keep up with the rapid changes in the Arctic, and they are currently utilizing all available resources to survive. Derocher, who was not involved in the research, praised it as being exceptionally well-crafted and perceptive.

Derocher expressed concern about the situation, as it raises the question of when the bears will deplete their energy. Studies indicate that some of the bears will be able to survive, but others are dangerously close to succumbing to starvation and dying.

Derocher stated that the evidence suggests it is improbable for polar bears to adjust to a land-based lifestyle.

Polar bears consume seals when they have access to sea ice. The majority of their diet while on ice is comprised of fat, according to Karyn Rode, a USGS wildlife biologist and co-author of the study.

According to Rode, they consume the most fatty diet out of all species globally.

Kristin Laidre, a biologist from the University of Washington who was not involved in the study, stated that polar bears rely on sea ice for feeding. This is because it allows them to access their main source of food, which is ice seals. Laidre also noted that polar bears evolved from grizzly bears and have adapted to a diet rich in fat from marine sources. She also mentioned their extraordinary ability to consume and break down lipids.

The team of biologists from the United States and Canada used video cameras attached to the bears’ collars, provided them with a specialized water diet to monitor their calorie intake and energy expenditure, and released them back into the wild to observe their behavior on land.

The bears’ foraging abilities were remarkable. Almost all of them consumed grass and kelp, while 10 of them indulged in berries. Eight of the bears devoured bird carcasses, a third of them gnawed on bones, and four of them dined on caribou antlers. In addition, some bears also ate bird eggs, a rodent, and a rabbit.

However, the bears had to use a significant amount of energy in their attempts to satisfy their hunger. On average, they journeyed 58 miles (93 kilometers), with one female cub travelling 233 miles (375 kilometers) in a span of three weeks.

According to Laidre, who leads the polar bear specialist group for the International Union for Conservation of Nature, this research contributes to the mounting evidence that polar bears are unable to survive on land as the loss of sea ice persists due to climate change.

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Stephanie Windeler, a journalist from the Associated Press, provided contributions from London.

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To access more information about climate coverage from AP, visit http://www.apnews.com/climate-and-environment.

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Please follow Seth Borenstein on X by searching for @borenbears.

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Source: wral.com