Secret Whale Refuge Unearthed

If you appreciate some of the greatest creatures on Earth, then it’s a discovery that will cheer your heart.

Scientists have stumbled upon a secret hideaway used by bowhead whales.

Located in an inaccessible part of the Greenland Sea, the hideaway has become a refuge for the whales, which are among the most endangered on the planet.

More than one hundred bowhead whales are thought to use the refuge, which has become a sanctuary that may help whale numbers recover from centuries of hunting.

Bowhead whales grow to 20 metres long, can weigh 75 tonnes and reputedly have the largest mouths of any animal. They used to live in four main groups around the world.

The largest, a population of an estimated 52,000 whales, lived in the Greenland and Barents Seas, around the island of Svalbard, which is part of Norway.

This is the largest abundance of bowhead whales reported from the Greenland Sea since the days of whaling in the sixteenth to seventeenth centuries

That was before 1611 when commercial whaling was initiated at Spitsbergen on Svalbard.

By 1911, commercial whaling ended. So many whales had been killed that too few remained to viably hunt any more.

Despite 100 years of protection, this population has shown no clear signs of recovery.

Just a few tens of bowhead whales are thought to survive in the region and the population is classified as Critically Endangered on the IUCN Red List.

However, over the last 20 years bowhead whales have been observed with increasing frequency in the Greenland Sea and in the coastal waters of Northeast Greenland, report scientists in the journal Polar Biology.

It isn’t yet clear if this is because there are more whales, or more people active at sea sighting them.

Another complication is that it is difficult to count bowhead whales.

This discovery provides renewed hope for the Spitsbergen stock of bowhead whales.

In summer, when most surveys are done, bowhead whales disperse. A recent satellite tracking of a single individual revealed that it moved between a wintering ground west of Spitsbergen and a summering ground of the East Greenland coast 700 kilometres to the south.

In previous centuries, whalers knew these movements, naming the two the Northern Whaling Ground and the Southern Whaling Ground, respectively, reports David Boertmann of the Arctic Research Centre, at Aarhus University in Denmark, in the journal.

Intriguingly however, some whales used to escape the hunters, disappearing in spring in dense pack ice floating near Northeast Greenland. The whalers couldn’t follow, and it’s not been clear since how important this region is to the whales.

Yet archaeological remains show that the Inuit people hunted bowheads along the coast in the fifteenth century.

The East Greenland coast was generally inaccessible to whaling vessels due to pack ice

Now research by David Boertmann and colleagues based at the Greenland Institute of Natural Resources, in Nuuk, Greenland and Copenhagen, Denmark, has revealed that the region is a hitherto unknown sanctuary for bowhead whales.

They made the discovery serendipitously, while conducting aerial surveys of walrus populations.

To spot walruses, observers flew in a plane over an expanse of open ocean water, surrounded by sea ice, known as a polynya.

To their surprise, they sighted a number of bowhead whales swimming in the polynya.

From the sightings, they can infer that perhaps more than 100 whales use the refuge.

“This is the largest abundance of bowhead whales reported from the Greenland Sea since the days of whaling in the sixteenth to seventeenth centuries,” the scientists say.

The sanctuary is in one of the shallowest parts of the Greenland Sea, with depths of less than 300 metres, meaning the whales can easily dive to catch their small crustacean prey.

“As the East Greenland coast was generally inaccessible to whaling vessels due to pack ice, the [polynya] may, during the whaling period, have acted as a summer refuge for bowhead whales,” write the scientists in the journal.

“Today the area certainly is of special conservation concern,” they say, and their study could be evidence that the number of bowhead whales is increasing.

“This discovery provides renewed hope for the Spitsbergen stock of bowhead whales that until now has shown only inconclusive signs of recovery despite more than 100 years of protection from whaling.”

However, they also caution that there are plans for oil exploration on the Greenland shelf of the Greenland Sea, and to ship zinc ore discovered in North Greenland.

So more research needs to be done into the bowhead whale populations to discover the likely impact of these plans on the animals.

Credits: BBC Earth 2015 

Bowhead Whales Thriving Off Alaska

Bowhead Whales in Alaska's Arctic waters appear to be thriving even as sea ice shrinks, offering a counterpoint to climate-change concerns that have prompted federal threatened status for some other northern animals such as polar bears.

"Multiple lines of evidence all point to the Alaska (bowhead) stock doing really well," said Craig George, senior wildlife biologist for the North Slope Borough, on Wednesday.

Temperatures in the Arctic have risen faster than anywhere else in the world, creating more open water that is apparently improving conditions for the tiny krill and other crustaceans the bowheads eat, scientists said.

Alaska's bowhead abundance appears to still be rising after decades of growth, while calf production is especially strong, they said.

"One of the best indicators of overall health of the herd is good calf production and we're sure seeing that," said George, a longtime bowhead expert from Utqiagvik, the nation's northernmost community.

Records show the whales are also fatter than they were about 30 years ago, with full stomachs in fall and low disease rates, George said.

Climate change has complicated life for subsistence whalers and hunters, who worry about animals' changing migration patterns and the deadly risks of traveling on thinner ice, said longtime Utqiagvik whaler Billy Adams, 52.

But the bowheads are doing well, he said.

In the 1980s, a decade of heavy sea ice, bowheads generally migrated past Alaska's northern coasts in September and October after leaving Canadian waters, Adams said.

Now, the migration starts in August and continues until the last few whales travel past in late November.

"That tells you there's a large increase in the population number of bowhead whales," said Adams, also an employee with the borough's wildlife department. "And they are lot fatter than what they used to be in the 1980s."

Alaska's bowheads, once decimated by commercial whaling that ended about a century ago, reached 17,000 during the last population count in 2011. The animals often travel beneath sea ice, ranging between Russia and Canada, with massive heads for ramming openings in ice and a foot-thick layer of insulating blubber.

With less ice, more sunlight is entering the water, and more wind is mixing up the ocean, creating conditions that appear to be boosting the bowhead's food supply, George said.

Storms sweeping across open water, a growing threat for many Alaska villages once protected by coastal sea ice, may be helping swirl nutrients.

Megan Ferguson, a scientist with National Marine Fisheries Service who runs the aerial survey program for Arctic marine mammals, said observers in 2016 and 2017 have seen huge groups of whales feeding off the mouths of Alaska rivers in summer.

The size of the aggregations is unprecedented, at least for Alaska waters, she said.

For four days in August 2016, surveyors detected a massive group of 600 bowheads feeding near the mouth of the Colville River, one-third of all the bowheads spotted that year, she said. That's many times larger than any previous single group counted by the agency.

A surveyor on that plane, Amy Willoughby with NMFS, said she was struck by general "shock and awe" of seeing the "mythical" number of whales. She called the sight "unbelievable."

The Colville flushed unusually large amounts of fresh water into salty Harrison Bay that summer, creating a zone rich with food where the animals can swiftly eat, Ferguson said.

"That area was historically a bowhead whale desert for us," Ferguson said. "If you asked us where the most boring place in our study area to observe whales was, we'd say Harrison Bay."

The agency doesn't have strong photos illustrating the giant whale gathering, she said. The team was "maxed out just just trying to record the data," she said.

Surveyors' top priority is looking out windows and counting. They usually see partial body shots and splashes as whales feed.

"We collect photos on an opportunistic basis," Ferguson said.

The team came across another out-sized group of bowheads late last summer, this time in the Camden Bay area, further to the east and nearer the Canadian border, she said.

Also "noteworthy" are the large number of calves spotted in some recent years, including an extremely high number in 2017, Ferguson said. That year, calves made up 12 percent of the overall number of whales detected.

Since the late 1970s, satellite records tracked sea-ice loss at about 10 percent a decade, George said. Meantime, bowhead abundance grew at a 3.7 percent annual clip through 2011.

George said that abundance trend may have risen in recent years, based on the strong calf-production rates and other data. The next population count doesn't occur until 2021.

A study led by George and published in 2015 focused on the girth of sub-adult whales, using the body measurements he and other scientists have collected for decades on the Slope, every time a whale is hauled ashore by subsistence crews.

It showed the whales grew plumper between 1989 and 2011.

How things will play out as sea ice continues to melt is anyone's guess, he said. The population won't keep rising forever. And the growth in girth may have leveled off in recent years, though a full analysis of that data is not complete, he said this week.

Also, future threats from increased Arctic ship traffic, newly introduced diseases or other unexpected factors could suddenly alter the picture.

"It's hard to say where this is all headed, but it's safe to say there won't be a textbook response like we learned about in wildlife biology," he said.

Credits : Anchorage Daily News, May 2018 

Songbirds Of the Arctic

The Critically Endangered Bowhead Whale is unusual amongst mammals because they, like songbirds, sing a diverse repertoire of many distinct and complex songs throughout the months-long polar night

Although singing complex songs is common amongst songbirds, most mammals lack this ability. But two species of baleen whales -- the humpback, Megaptera novaeangliae, and the bowhead, Balaena mysticetus -- are amongst the rare exceptions.

The more ubiquitous humpback is better known than the mysterious bowhead whale, whose geographic range is restricted to the Arctic. In fact, bowhead whales got their name from their massive, dome-shaped skull that they use to bash through sea ice that may be as much as 60 centimeters (2 feet) thick. They have the largest mouth of any animal, festooned with two rows of about 300 vertical baleen plates, which at 300-450 centimeters (9.8 - 15 feet) long are the largest of any whale. Bowhead whales are insulated against frigid Arctic waters with an exceptionally thick layer of blubber.

Bowhead whales are slow swimmers, with a top speed of about 6mph, and they don’t tend to make deep dives. This, combined with their economically valuable blubber and baleen almost pushed them into extinction. Worldwide, there were probably more than 50,000 bowhead whales, but this species was hunted until fewer than 3,000 animals remained alive in the early 1920s . There are four distinct populations, some of which are recovering better than others from the ravages of hunting. The study whales were part of the Spitsbergen bowhead whale population, one of the smaller groups, which was hunted almost to extinction in the 1600s and was recently estimated to number roughly 200 animals.

Serendipitous Discovery:

Oceanographer Kate Stafford, in the Applied Physics Laboratory at the University of Washington, is an expert on using sound to track and study marine mammals. She first identified bowhead whales singing in some audio recordings made near Greenland in 2007.

In this new study, Dr. Stafford and her collaborators, Christian Lydersen and Kit Kovacs of the Norwegian Polar Institute, and Øystein Wiig of the Natural History Museum at the University of Oslo, expanded the original five-month song collection from that earlier study to cover more than three years.

“We were hoping when we put the hydrophone out that we might hear a few sounds,” Dr. Stafford said in a statement. “When we [listened], it was astonishing: Bowhead whales were singing loudly, 24 hours a day, from November until April.”

To make these audio recordings, Dr. Stafford and her collaborators placed special underwater recording equipment in the western Fram Strait, a frigid water channel that runs north-south between Greenland and the Svalbard archipelago.

The Fram Strait, the only deep water connection between the Arctic Ocean and the other oceans of the world, connects the Arctic and the Greenland Seas. The hydrophone was located roughly 80 meters (262 feet) below the surface of the sea in the Fram Strait in water that was 1,020 meters (3346 feet) deep. The hydrophone remained in place from 2010 to 2014.

Bowhead whales sing many intricate but ephemeral songs:

The research team recorded bowhead whale songs 24 hours per day throughout the polar winter, and recorded the greatest number of songs in December and January.

These recorded bowhead whale songs, the largest collection amassed so far, revealed that these marine mammals have a surprisingly varied and constantly changing vocal repertoire.

“If humpback whale song is like classical music, bowheads are jazz,” Dr. Stafford explained. “The sound is more freeform.”

“With bowheads, you never know where they’re going,” Dr. Stafford added.

During the three year study period, a total of 184 song types were recorded -- a number that increased each year during the three-year study. The fewest song types were recorded in 2010 – 2011 (39 song types total, 895 recordings). Both 2012 – 2013 (69 song types total, 1338 recordings) and 2013 – 2014 (76 song types total, 998 recordings) had approximately twice as many different song types.

The variety of bowhead whale songs was so surprising that the researchers compared them to songbirds.

As many bird watchers know, songs are distinct from calls because of their auditory complexity: songs contain intricate and unique phrasing that must be learned. Birds use song to identify themselves as individuals as well as to impress any lady birds that may be listening in, and to defend a territory.

But whales are not songbirds, nor do they use sound in identical ways.

“For marine mammals, acoustics is how they do everything,” Dr. Stafford elaborated. “Humans are mostly visual animals, but marine mammals live in a three-dimensional habitat where sound and acoustic information is how they navigate, how they find food, how they communicate.”

For these reasons, the complexity and distinct musical phrasing of bowhead whale songs was remarkable. Yet most bowhead whale songs were performed over a very short time period -- sometimes just a few hours or days and were never heard again -- and most songs were seldom recorded over time periods of longer than one month. Yet, at the same time, a few song types were recorded throughout the entire winter.

The overall trend for all years was a progression of song types appearing and then disappearing over time with the greatest within-year diversity occurring in January for all three years examined. Of the 3231 song recordings made during the three year study, slightly over half (53%) contained only a single song type, while two different songs occurred in 37% of the recording periods. Only a few recording periods included song diversity of 3 (9%) or 4 (less than 1%) distinct songs.

“[W]hen we looked through four winters of acoustic data, not only were there never any song types repeated between years, but each season had a new set of songs,” Dr. Stafford said.

This contrasts with what we’ve learned about humpback whales. That species, which breeds off the coasts of Hawaii and western Mexico, has a common song shared by males within each population. Although this song changes from one breeding season to the next, it basically remains the same, with only slight changes, throughout each breeding season.

“It was thought that bowhead whales did the same thing, based on limited data from springtime,” Dr. Stafford explained. “But those 2008 recordings were the first hint, and now this data confirms that bowhead whale songs are completely different from the humpbacks’.”

This study generates more questions than it answers.

Like all good research, this study provides the scientific basis for asking a plethora of new questions about bowhead whales. For example, it’s suspected that the Arctic winter is bowhead whale breeding season, and that male whales sing to impress the ladies or to compete in acoustic competitions with other males. Or both. But at this time, no one knows whether each whale performs just one special melody or selects specific tunes -- or mixes and matches short phrases -- from a larger oeuvre.

“Why are they changing their songs so much?” Dr. Stafford said. “In terms of behavioral ecology, it’s this great mystery.”

This study suggests bowhead whales may be similar to cowbirds and meadowlarks -- songbirds that learn and perform a diverse and dynamic repertoire of songs -- maybe because novelty offers some advantage.

Of course, it’s conceivable that females sing. It’s also possible that the four different bowhead whale populations maintain their genetic isolation from each other through their songs. For example, previous research found that the two North Pacific populations -- the Okhotsk Sea population and the similarly-sized study population, the Spitsbergen bowheads -- are genetically isolated from each other, indicating that individuals rarely roam between these two populations (link). But considering that these four bowhead whale populations will not remain isolated from each other as Arctic sea ice grows ever thinner, this raises questions about whether song can maintain these populations’ genetic isolation, particularly in view of this species’ extraordinary diversity in song types.

Answers to these questions would provide a reasonable biological context for this vast annual Arctic concert, but because it’s impossible to track or observe whales during the Arctic winter using current technologies, it’s impossible to know the reasons that govern bowhead whale singing.

“Bowhead whales do this behavior in the winter, during 24-hour darkness of the polar winter, in 95 to 100 percent sea ice cover. So this is not something that’s easy to figure out,” Dr. Stafford said. “We would never have known about this without new acoustic monitoring technology.”

Already, Dr. Stafford and her collaborators are developing plans and new technologies so they, say, can attach acoustic tags to individual bowhead whales that will record its songs and journeys. Not only would this help them answer the many questions they have about singing, it will also give them more data they need to make a more accurate population estimate. Further, such technology may help Dr. Stafford and her collaborators get a realistic idea of how thinning Arctic sea ice is affecting these animals.

“Bowheads are superlative animals: they can live 200 years, they’ve got the thickest blubber of any whale, the longest baleen, they can break through ice,” Dr. Stafford said. “And you think: They’ve evolved to do all these amazing things. I don’t know why they do this remarkable singing, but there must be a reason.”

Credits : Forbes Magazine 2018 

Introduction

This Blog Is Exclusively Dedicated to the Conservation and Safety of Bowhead Whales.

Bowhead Whales are considered the Greatest Singers in the Frigid Ocean in the Arctic.

They Live till they are 200 years and have thick Blubber.

It is My Hope that This Blog will create some awareness about these Unique Long Lived Ocean Based Mammals.