Research from the 91̽�� shows that endangered blue whales are present and singing off the southwest coast of India. The results suggest that conservation measures should include this region, which is considering expanding tourism.

Analysis of recordings from late 2018 to early 2020 in , an archipelago of 36 low-lying islands west of the Indian state of Kerala, detected whales with a peak activity in April and May.

The was published in May in the journal Marine Mammal Science.

“The presence of blue whales in Indian waters is well known from several strandings and some live sightings of blue whales,” said lead author , a 91̽��doctoral student in oceanography. “But basic questions such as where blue whales are found, what songs do they sing, what do they eat, how long do they spend in Indian waters and in what seasons are still largely a mystery.”

Answers to those questions will be important for the region, which is also experiencing effects of climate change.

“This study provides conclusive evidence for the persistent occurrence of blue whales in Lakshadweep,” Panicker said. “It is critical to answer these questions to draw up science-based management and conservation plans here.”

While enormous blue whales feed in the waters around Antarctica, smaller pygmy blue whale populations are known to inhabit the Indian Ocean, the third-largest ocean in the world.

In previous preliminary research, Panicker, who grew up in Cochin, India, talked to local fishers who reported seeing whale blows during the spring months.

But since whales surface only occasionally and sound waves travel well in water, the best way to study whales is the same way they communicate.

The typical blue whale song is a series of one to six low moans, each up to 20 seconds long, below the threshold of human hearing. The pattern and number of moans varies for different populations. Songs provide insights into this poorly studied population; a possible new song was in the central Indian Ocean and off the coasts of Madagascar and Oman.

For the new study, scuba divers placed underwater microphones at two ends of Kavaratti Island. Other studies in nearby waters suggested that the presence of blue whales would be seasonal, and recordings confirmed their presence between the winter and summer monsoons.

“Our study extends the known range of this song type a further 1,000 kilometers (620 miles) northwest of Sri Lanka,” Panicker said. “Our study provides the first evidence for northern Indian Ocean blue whale songs in Indian waters.”

The researchers believe that the whales are likely resident to the northern Indian Ocean, and come to the Lakshadweep atoll seasonally.

“The Indian Ocean is clearly important habitat for blue whales — an endangered species that is only very slowly recovering from 20^th-century commercial and illegal whaling, especially in the Indian Ocean,” said senior author , an oceanographer at the 91̽��Applied Physics Laboratory.

Future work by another 91̽��research group will use recordings of blue whales in the Indian Ocean to calculate their historic numbers and better understand how historic whaling affected different populations in this region.

This research was funded by the U.S. Navy’s Office of Naval Research through its Marine Mammal and Biology Program.

For more information, contact Panicker at dpanic@uw.edu or Stafford at kate2@uw.edu. (Note: Panicker is on Maldives Time, 12 hours ahead of Pacific Daylight Time.) More images available at

Spring is the time of year when birds are singing throughout the Northern Hemisphere. Far to the north, beneath the ice, another lesser-known concert season in the natural world is just coming to an end.

A 91̽�� study has published the largest set of recordings for bowhead whales, to discover that these marine mammals have a surprisingly diverse, constantly shifting vocal repertoire.

The , published April 4 in , a journal of the United Kingdom’s Royal Society, analyzed audio recordings gathered year-round east of Greenland. This population of bowhead whales was hunted almost to extinction in the 1600s and was recently estimated at about 200 animals. Audio recordings gathered from 2010 to 2014 indicate a healthy population, and include 184 different songs.

“If humpback whale song is like classical music, bowheads are jazz,” said lead author , an oceanographer at the UW’s Applied Physics Laboratory. “The sound is more freeform. And when 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.”

Stafford has recorded whales’ sounds throughout the world’s oceans as a way to track and study marine mammals. She first detected bowhead whales singing off the other side of Greenland in 2007. A previous study by Stafford of the Spitsbergen whales off west Greenland that the whales were singing continuously during the winter breeding season, the first hint that there may be a healthy population in that area.

“We were hoping when we put the hydrophone out that we might hear a few sounds,” Stafford said of the earlier study. “When we heard, it was astonishing: Bowhead whales were singing loudly, 24 hours a day, from November until April. And they were singing many, many different songs.”

The new paper extends that initial five-month dataset, and confirms that bowhead whales sing in this region regularly from late fall to early spring. In fact the hydrophones, which are underwater microphones, picked up slightly more singing in the later years of the study. But what was most remarkable was the relentless variety in the animals’ songs, or distinct musical phrases.

The only other whale that sings elaborate songs — humpback whales — are widely studied in their breeding grounds off Hawaii and Mexico. The humpback’s melodious song is common to each population of males and shifts slightly during the winter breeding season. Each population debuts a new tune in the spring.

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

Animal songs are not the same as animal calls because songs are complex, distinct musical phrases that must be learned. Many birds and mammals use songs to identify themselves as individuals or as members of a group, among other uses.

“For marine mammals, acoustics is how they do everything,” Stafford said. “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.”

Singing whales, like birds, may be doing some combination of acoustic competition with other animals and attracting mates, Stafford said. But little is known about the bowhead whales’ singing: whether only males make these sounds, whether individuals can share songs, and, most importantly, why their tune changes all the time.

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

The new data suggest bowhead whales may be similar to cowbirds and meadowlarks, birds that learn a diverse, ever-changing repertoire of songs, maybe because novelty offers some advantage.

“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,” Stafford said. “We would never have known about this without new acoustic monitoring technology.”

Current research placing radio tags on bowhead whales may someday explain why this whale has evolved to become such a versatile virtuoso.

“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,” 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.”

Other co-authors are and at the Norwegian Polar Institute in Tromsø and at the University of Oslo’s Natural History Museum. The research was funded by the Norwegian Polar Institute, the Svalbard Environmental Protection Fund, Svalbard Science Forum, the Fram Centre Incentive Fund and the Norwegian Research Council.

Watch Stafford’s TEDx talk in Geneva about sound in marine habitats:

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For more information, contact Stafford at kate2@uw.edu or 206-685-8617. Note: Stafford is doing international fieldwork April 6-23. During that time, direct media inquiries to co-author Kit Kovacs at kit.kovacs@npolar.no or +47 77750526.

Norwegian Research Council: Grant 244488/E10

The annual migration of some beluga whales in Alaska is altered by sea ice changes in the Arctic, while other belugas do not appear to be affected.

A led by the 91̽�� finds that as Arctic sea ice takes longer to freeze up each fall due to climate change, one population of belugas mirrors that timing and delays its migration south by up to one month. In contrast, a different beluga population, also in Alaska, that migrates and feeds in the same areas doesn’t appear to have changed its migration timing with changes in sea ice.

The paper was published Dec. 21 in the journal Global Change Biology.

“The biggest take-home message is that belugas can respond relatively quickly to their changing environment, yet we can’t expect a uniform response across all beluga populations,” said lead author , a postdoctoral researcher at the UW’s .

“If we’re trying to understand how these species are going to respond to climate change, we should expect to see variability in the response across populations and across time,” Hauser said. “That may complicate our predictions for the future.”

Two genetically distinct beluga populations spend winters in the Bering Sea, then swim north in the early summer as sea ice melts and open water allows them passage into the Beaufort and Chukchi seas. There they feast all summer on fish and invertebrates before traveling back south in the fall. Other research suggests the whales are taught by their mothers when to migrate and which route to take, so it was unclear if belugas would be responsive to sea ice changes.

The Chukchi beluga population’s response to follow sea ice timing and delay migration likely means the whales are opportunistically feeding later into the fall, but researchers don’t yet know if that delay is overall beneficial. On one hand, the whales might be gaining valuable food resources, but they also risk getting blocked from their migration path south if the ice quickly freezes up and catches them off guard.

In contrast, the Beaufort beluga population’s apparent indifference to sea ice timing is surprising, Hauser said, given that both populations frequent many of the same feeding areas and otherwise appear to have similar life histories. Perhaps the Beaufort whales have a tradition of feeding elsewhere that requires they move away earlier in the fall, regardless of sea ice characteristics, she explained.

“This all suggests that beluga whales can respond to their changing Arctic conditions, although all populations will not necessarily respond the same,” Hauser said.

Very few studies exist on beluga whales, a marine mammal that lives in some of the Earth’s harshest conditions. Analyses on their body condition or population trajectories will need to take place before researchers can say whether their response — or lack thereof — to environmental change is beneficial or detrimental to the health of the populations.

Researchers, however, note that when they do see changes, they are happening quickly — within a 10-year span for whales that often live to be over 60 years old. That means migration patterns that are inherited over generations are changing within the lifespans of multiple generations of whales, Hauser said.

In this study, the researchers used migration data collected intermittently from two different periods — referred to in the paper as “early” and “late” — for both populations, corresponding roughly to the 1990s and 2000s decades. Satellite-linked tags attached to the whales tracked their movements around and away from the high Arctic feeding grounds.

They also used acoustic data from two underwater hydrophones that recorded the vocalizations of marine mammals each day for about six years. The social signals — an assortment of squeaks, whistles and cries — told researchers when belugas were present up to about 3 miles from the instrument. The use of underwater microphones is a good way to detect belugas in their dark, icy environment, said , a co-author and oceanographer at the UW’s Applied Physics Laboratory who uses the underwater microphones to study a range of animals in the Arctic.

These two datasets let the researchers track exactly when belugas passed certain key points along their fall migration, then correlate those days to regional sea ice information.

“One of the predictions of climate change is animals are going to change their seasonal presence in a region,” Stafford said. “This study shows that at least one population of belugas might be adapting to rapid changes in its environment. We can’t be sure, but this study is a start in documenting how an Arctic species is reacting to these changing conditions.”

Other co-authors are and of the UW; of North Slope Borough in Utqiaġvik, Alaska; and of Fisheries and Oceans Canada.

This analysis was funded by the National Science Foundation’s , NASA and the UW’s . Passive acoustic data collection was funded by grants from the National Science Foundation’s Arctic Observing Network and the Russian-American Long-term Census of the Arctic.

Many individuals and organizations supported beluga whale tagging, including the Alaska Beluga Whale Committee, North Slope Borough, Village of Point Lay, the Inuvialuit Hunter and Trapper Committees and Fisheries and Oceans Canada.

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For more information, contact Hauser at dhauser@uw.edu or 907-474-1811.

A study of the narrow passage of the Bering Strait uses underwater microphones to track the whales by their sounds. Three years of recordings reveal more detections of both Arctic and sub-Arctic whales traveling through the narrow choke point.

, an oceanographer with the 91̽��’s Applied Physics Laboratory, will present the results Feb. 26 at the meeting in Honolulu.

The recordings show Arctic beluga and bowhead whales migrating seasonally through the region from the Arctic south to spend winter in the Bering Sea. They also detect large numbers of sub-Arctic humpback, fin and killer whales traveling north through the Bering Strait to feed in the biologically rich Chukchi Sea.

“It’s not particularly surprising to those of us who work up in the Arctic,” Stafford said. “The Arctic seas are changing. We are seeing and hearing more species, farther north, more often. And that’s a trend that is going to continue.”

Stafford placed microphones below the water’s surface and recorded in summer and early winter from 2009 to 2012 as part of a . Melodious humpback whale songs showed up regularly on recordings into late fall. Fin and killer whales, which are southern species that seldom travel into Arctic waters, were heard into early November.

“These animals are expanding their range,” Stafford said. “They’re taking advantage of regions in seasons that they may not have previously.”

The recordings also picked up ships using the ice-free summers to travel through two international shipping lanes. This poses an increased risk of collisions between whales and ships, and of noise pollution.

“Marine mammals rely primarily on sound to navigate, to find food and to find mates. Sound is their modality,” Stafford said. “If we increase the ambient sound level, it has the potential to reduce the communication range of cetaceans and all marine mammals.”

The Bering Strait is famous as a land bridge that prehistoric humans used to travel from Russia to North America. Today, the waterway is 58 miles wide and maximum 160 feet deep, with about one-third of its span in U.S. waters and the rest in Russia. The two coasts are quite different, Stafford said, which makes the international collaboration essential to understanding the full environment.

A by Stafford and other scientists includes visual sightings of killer whales, a quieter southern-dwelling whale, just north of the strait in the southern Chukchi Sea. Killer whales are now seen fairly regularly in this area, which is being considered for oil and gas exploration.

“The Arctic areas are changing,” Stafford said. “They are becoming more friendly to sub-Arctic species, and we don’t know how that will impact Arctic whales. Will they be competitors for food? Will they be competitors for habitat? Will they be competitors for acoustic space, for instance these humpbacks yapping all the time in the same frequency band that bowheads use to communicate? We just don’t know.”

Stafford supports the idea of slowing ship speeds in the Bering Strait, reducing motor noise and the chance of ship strikes.

Another suggestion to protect whales builds on tagging work showing that bowhead whales tend to travel up the U.S. side on the way north in the spring and on the Russian side on their way back in the fall. The proposal suggests that ships follow the American coast in the fall and the Russian coast in the spring to reduce interactions between ships and whales.

Still to be explored is whether the increased whale travel through the region is due to rising whale populations, expanded ranges, or both. Logbooks from Soviet whaling ships in the mid-to-late 20th century report sub-Arctic whales in the region, but none were seen from about 1980 to 2010.

“The question is, are these whale populations recovering and so they’re reoccupying former habitat, or are they actually invading the Arctic because they can, because there is less seasonal sea ice?” Stafford said.

Collaborators on the research are Janet Clarke at Leidos Inc. and Sue Moore at the National Oceanic and Atmospheric Administration. The research was funded by the U.S. National Science Foundation, the National Oceanic and Atmospheric Administration, and the Interior Department’s Bureau of Ocean and Energy Management.

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For more information, contact Stafford at 206-685-8617 or stafford@apl.washington.edu.

Stafford will speak in Session #102 at the Ocean Sciences meeting in Honolulu on Wednesday, Feb. 26 at 2:45 p.m. in room 316A.