The ice sheets covering the North Pole have been around for millions of years. But for the last few decades, scientists have watched them grow thinner and weaker. That’s not the only thing losing out up north, according to a recent study by the U.S. Geological Survey. Polar bears are losing valuable space and as a result are finding it more difficult to locate the food they need to survive.
Scientists have noticed that the polar bears will move inland and find alternative sources of food, such as birds’ nests and even vegetation. It was assumed they would simply adapt to changing circumstances. According to the study, that may not be possible. The bears rely on a marine diet which is typically rich in fat – exactly where there are much needed calories and nutrients to keep the big animal up and running.
The study also noted that among the population of bears, not all of them were moving toward a terrestrial mode of finding food. It may be that it is just in their genes to look for food in a place where it has always been abundant and nutritious. Observing the bears, it was seen that fewer than thirty even made for the birds eggs – which would be a reasonable substitute for fish, being dense and rich in fat and protein.
What the researchers are sure about is that the size and survival rates are getting worse and worse. Polar bears are not as healthy when they eat substandard diets, and this situation could go from a gradual decline to a serious issue. This in turn could have wide-reaching implication for the polar ecosystem as a whole.
One possibility is that the remaining animals do permanently move inland. While not guaranteed, it may ensure the survival of a small number of the population. As a contrast, the northern grizzly bear is one of the smallest known and its population is spread around. Rather than eating marine life, it maintains a standard diet and thus is smaller. If the polar bears move inland, this could create competition for both species and lead to a further decline in both populations.
On the upside, if the sea ice continues to break apart, it’s just possible that new avenues for polar fishing may keep these animals alive.
