The image of a polar bear standing solitary as ice melts is often used as a symbol of the world’s rapidly changing climate. And now data reveals that this image is becoming more of a reality. Polar bears in Canada’s Western Hudson Bay, an inland sea connected to the Arctic Ocean, are dying at a fast rate.
A government survey estimates that there are now 618 polar bears in the area, including the nearby town of Churchill which is also referred to as the ‘Bear Capital of the World’, down from 842 in 2016. The survey also revealed that the number of female bears and cubs, in particular, has seen a dramatic decline.
This additional data shows how climate change is becoming deadly for polar bears, with some other studies showing that polar bears will be extinct by the end of the century.
Polar bears and the Arctic ice
For polar bears, the Arctic ice is crucial for survival. They use the ice to travel long distances to new areas. They hunt for seals by finding their dens or sitting next to gaps in the ice, waiting for the unsuspecting prey to pop up. Sometimes, pregnant females dig in the sea ice to create maternity dens, where they give birth and take care of their cubs.
The sea ice is also the primary habitat of polar bears. However, with the sea ice melting, polar bears are being forced to move to land during the summer, meaning they have to swim more frequently and for longer distances to catch seals. More time in the water also means that more energy is required, so they have to work harder than ever for their dinner.
Polar bears are Olympian-grade swimmers, however they are at risk of drowning if the weather turns during a long-distance swim. Longer swims also put cubs at risk.
Melting ice and declining population
Climate change in recent years has put the polar bears’ habitat at risk, as the ice is melting at a faster rate. Multiple studies show that the temperatures in the Arctic are rising nearly four times as fast as the global average, and the Arctic sea ice extent has declined since 1979 for every month of the year.
In 2020, the National Geographic in an article stated that at its maximum in March, the ice covers nearly the entire Arctic Ocean, almost six million square miles. It melts back during summer, reaching its lowest point in September. In July during the 1980s, the ice covered an average of about 3.8 million square miles, roughly the area of the US or Canada. However, in July 2020, sea ice covered only about 2.8 million square miles. Since 1979, Arctic sea ice has declined by an average of 27,000 square miles a year, an area the size of North Dakota that melts each year and doesn’t grow back.
Experts have long noted that the disappearance of sea ice will open up the dark Arctic Ocean, which will absorb — rather than reflect — heat, causing global heating to escalate further. It will also upend the region’s ecosystem, harming everything from algae to large animals such as seals and polar bears that need the sea ice for hunting.
The melting ice will also have a negative impact on polar bears, and multiple studies have reflected this. According to a 2020 research, the declining sea ice concentrations are affecting the behaviour, health and reproductive success of polar bears. The study had showed that polar bears were spending more time on land and fasting for longer periods of time. Moreover, mother bears were producing smaller cub litters.
The research also established the relationship between sea-ice availability and the bears’ body fat and variable litter sizes. They projected that the normal cub litter size of two may decrease within the next three polar bear generations (37 years), mainly due to the projected decline of sea ice in the coming decades.
The recent estimates are in line with previous studies. The recent survey has revealed that there’s a higher concentration of deaths in young bears and females in Western Hudson Bay. Andrew Derocher, a biology professor at the University of Alberta who has studied Hudson Bay polar bears for nearly four decades, told the Associated Press, “It certainly raises issues about the ongoing viability.
Stephen Atkinson, the lead author who has studied polar bears for more than 30 years, also stated that the capacity for polar bears in the Western Hudson Bay to reproduce will diminish, “because you simply have fewer young bears that survive and become adults.”
But why are polar bears so important?
Polar bears are beautiful animals that serve an important part of the ecosystems in which they live. They are crucial to the environment as they keep biological populations in balance. They are considered the apex predator in the region and without their big kills, food for scavengers such as Arctic foxes and birds will dwindle.
Additionally, if the number of polar bears dwindle, the population of seals will rise, endangering the existence of crustaceans and fish that are an important food source for local human populations as well as other Arctic wildlife.
With inputs from agencies
Read all the Latest News, Trending News, Cricket News, Bollywood News,
India News and Entertainment News here. Follow us on Facebook, Twitter and Instagram.
