Saturday, May 15, 2021
Home Environment A Whale Chorus Shows How Climate Change Could Affect Migration

A Whale Chorus Shows How Climate Change Could Affect Migration

Other climate-related patterns, such as the highly unpredictable and early summer plankton bloom, could also be at play, according to the scientists

Eerie wails, explosive trumpets, and ghostly moans. The sounds from the underwater recorders had a story to tell, even without a single intelligible word: the whales had stayed put.

The recordings gathered during the 2018-2019 winter in the freezing cold Arctic waters of Canada proved that a population of bowhead whales had skipped their usual migration south.

Scientists believe this behavior — never previously detected — could be driven by the effects of climate change and be a potential harbinger of shifting dynamics across the region’s ecosystem.

Follow NewsGram on Quora Space to get answers to all your questions.

Ordinarily, the approximately 20,000 bowheads that make up the Bering-Chukchi-Beaufort (BCB) population around Canada have a fairly predictable migration pattern spanning 6,000 kilometers (3,700 miles).

They spend the winter in part of the Bering Sea, which lies between Russia and Alaska, and head north then east to the Beaufort Sea and Canada’s Amundsen Gulf in the summer, before returning in the autumn.

A bowhead whale spy hops off the coast of the western Sea of Okhotsk. Wikimedia Commons

But in winter 2018-2019, something different happened. Residents in the Canadian region reported seeing bowheads long after they would normally have disappeared south.

A team of scientists decided to comb through hours of audio recorded by underwater devices that are dotted around the region for regular data collection, listening for unusual sounds.

They found them: the distinctive calls of bowhead whales that should have been in their southern winter grounds but had stayed put.

Assisted by a trained computer program, they even found recordings of bowheads singing, a behavior believed to be associated with mating, which has never been recorded in the summer grounds before.

The whale noises appeared in between 0.5 to 3.0 percent of recording files collected between October to April at four summer spots.

The finding was highly unusual: recordings from some of the same and separate sites in the summer grounds in previous years picked up no whale sounds after October or December, depending on the location.

“The evidence is clear that BCB bowheads overwintered in their summer foraging region in the eastern Beaufort Sea and the Amundsen Gulf during the 2018-2019 winter and as far as we know, this is the first time it has been reported,” says the study published Wednesday in the Royal Society Open Science journal.

Ecosystem shift underway 

Less clear however is why this happened, with the authors positing various theories mostly linked to climate change.

The distinctive calls of bowhead whales that should have been in their southern winter grounds but had stayed put. Wikimedia Commons

One possible factor could be shifting ice cover, with less ice than usual seen in the summer grounds during the 2018-2019 winter season.

But the record minimum ice concentration actually came in 2015-2016.

That suggests “ice, and particularly timing and locations, is important but not the only factor,” said Stephen Insley of the Wildlife Conservation Society Canada, who helped lead the study.

Another possible explanation is “predator avoidance,” with the bowheads steering clear of orca whales that are more frequently seen in some areas as warming seas lead to decreased ice cover.

Other phenomena linked to climate change could also be at play, like the increasingly erratic and early summer plankton bloom — whales could be spending winter in their summer grounds to ensure they catch the key food source, the scientists suggest.

A bowhead whale is tail-slapping in the coastal waters of the western Sea of Okhotsk. Wikimedia Commons

Insley suspects water temperature is playing a key role in the unusual behavior, with bowheads are known to avoid water outside a narrow range of around -0.5 to 2 degrees centigrade.

If the bowheads are responding to the effects of climate change, they would be far from alone, Insley told AFP.

ALSO READ: Population Of Humpback Whales Is Rising, Scientists Warn Climate Change Poses A Danger

“The whole region is undergoing dramatic change and we’re just seeing the beginning of it. Many sub-Arctic species are moving north,” he said.

“It’s a complete ecosystem shift underway and there will be winners and losers.”

The team is continuing to record in the region and hopes to correlate its data with information about ocean temperatures to determine any link.

“If the avoidance of warm ocean temperatures were the primary driver of this anomalous behavior, it may be a significant warning sign for bowhead whales,” the study cautions. (VOA/KB)



Most Popular

Rani Abbakka: The First Woman Freedom Fighter Of India

By- Khushi Bisht Rani Abbakka who is also known as Abbakka Mahadevi was the first queen of Ullal. Known for her unwavering bravery, she was...

5 Tips For Getting Through A Long-Haul Flight

By Carol Trehearn A holiday in the sun! Travel and fun have been in limited supply during the past year, so it’s understandable that many...

The Most Stylish Hollywood Mother Of The Bride Dresses

By John Miller Mothers of the bride have always held great importance in the wedding. She is always by the side of the bride, and...

Is Dental Checkup In Pandemic Safe?

Want to go for a dental checkup but afraid due to the ongoing Covid-19 pandemic? Take heart, according to a small study SARS-CoV-2 infection...

Here’s How A Man Turned Covid19 Crisis Into An Opportunity

Even as the Covid pandemic has battered many lives across India, some have turned this crisis into an opportunity. One such person is Farooq...

Namdhari Sect Providing Education To Slum Children

An open-air school set up by the Namdhari sect of Sikhism led by spiritual head Thakur Dalip Singh in a street of Jalandhar city...

Diets Don’t Work In The Long-term, But Lifestyle Changes Do

For decades, diet conversations globally have ranged from the simple and straightforward to elaborate and convoluted, the latter sometimes even bordering on crazy. In...

How To Choose The Right SPF

SPF known as Sun Protection Factor is an indicator of how effectively it can protect the skin from harmful sun rays. We need to...

Recent Comments