According to the fossil record, cetaceans — whales, dolphins and their relatives — evolved from four-legged land mammals that returned to the oceans beginning some 50 million years ago. Today, their descendants are threatened by a different land-based mammal that has also returned to the sea: humans.

Thousands of whales are injured or killed each year after being struck by ships, particularly the large container vessels that ferry 80% of the world’s traded goods across the oceans. Collisions are the leading cause of death worldwide for large whale species. Yet global data on ship strikes of whales are hard to come by — impeding efforts to protect vulnerable whale species. A new study led by the 91̽�� has for the first time quantified the risk for whale-ship collisions worldwide for four geographically widespread ocean giants that are threatened by shipping: blue, fin, humpback and sperm whales.

In a published online Nov. 21 in Science, researchers report that global shipping traffic overlaps with about 92% of these whale species’ ranges.

“This translates to ships traveling thousands of times the distance to the moon and back within these species’ ranges each and every year, and this problem is only projected to increase as global trade grows in the coming decades,” said senior author , a 91̽��assistant professor of biology and researcher with the .

“Whale-ship collisions have typically only been studied at a local or regional level — like off the east and west coasts of the continental U.S., and patterns of risk remain unknown for large areas,” said lead author Anna Nisi, a 91̽��postdoctoral researcher in the Center for Ecosystem Sentinels. “Our study is an attempt to fill those knowledge gaps and understand the risk of ship strikes on a global level. It’s important to understand where these collisions are likely to occur because there are some really simple interventions that can substantially reduce collision risk.”

The team found that only about 7% of areas at highest risk for whale-ship collisions have any measures in place to protect whales from this threat. These measures include speed reductions, both mandatory and voluntary, for ships crossing waters that overlap with whale migration or feeding areas.

“As much as we found cause for concern, we also found some big silver linings,” said Abrahms. “For example, implementing management measures across only an additional 2.6% of the ocean’s surface would protect all of the highest-risk collision hotspots we identified.”

“Trade-offs between industrial and conservation outcomes are not usually this optimal,” said co-author , a research scientist with the National Oceanic and Atmospheric Administration and the University of California, Santa Cruz. “Oftentimes industrial activities must be greatly limited to achieve conservation goals, or vice versa. In this case, there is a potentially large conservation benefit to whales for not much cost to the shipping industry.”

Those highest-risk areas for the four whale species included in the study lie largely along coastal areas in the Mediterranean, portions of the Americas, southern Africa and parts of Asia.

The international team behind the study, which includes researchers across five continents, looked at the waters where these four whale species live, feed and migrate by pooling data from disparate sources — including government surveys, sightings by members of the public, tagging studies and even whaling records. The team collected some 435,000 unique whale sightings. They then combined this novel database with information on the courses of 176,000 cargo vessels from 2017 to 2022 — tracked by each ship’s automatic identification system and processed using an algorithm from Global Fishing Watch — to identify where whales and ships are most likely to meet.

The study uncovered regions already known to be high-risk areas for ship strikes: North America’s Pacific coast, Panama, the Arabian Sea, Sri Lanka, the Canary Islands and the Mediterranean Sea. But it also identified understudied regions at high risk for whale-ship collisions, including southern Africa; South America along the coasts of Brazil, Chile, Peru and Ecuador; the Azores; and East Asia off the coasts of China, Japan and South Korea.

The team found that mandatory measures to reduce whale-ship collisions were very rare, overlapping just 0.54% of blue whale hotspots and 0.27% of humpback hotspots, and not overlapping any fin or sperm whale hotspots. Though many collision hotspots fell within marine protected areas, these preserves often lack speed limits for vessels, as they were largely established to curb fishing and industrial pollution.

For all four species the vast majority of hotspots for whale-ship strikes — more than 95% — hugged coastlines, falling within a nation’s exclusive economic zone. That means that each country could implement its own protection measures in coordination with the U.N.’s International Maritime Organization.

“From the standpoint of conservation, the fact that most high-risk areas lie within exclusive economic zones is actually encouraging,” said Nisi. “It means individual countries have the ability to protect the riskiest areas.”

Of the limited measures now in place, most are along the Pacific coast of North America and in the Mediterranean Sea. In addition to speed reduction, other options to reduce whale-ship strikes include changing vessel routings away from where whales are located, or creating alert systems to notify authorities and mariners when whales are nearby.

“Lowering vessel speed in hotspots also carries additional benefits, such as reducing underwater noise pollution, reducing greenhouse gas emissions, and cutting air pollution, which helps people living in coastal areas,” said Nisi.

The authors hope their global study could spur local or regional research to map out the hotspot zones in finer detail, inform advocacy efforts and consider the impact of climate change, which will change both whale and ship distributions as sea ice melts and ecosystems shift.

“Protecting whales from the impact of ship strikes is a huge global challenge. We’ve seen the benefits of slowing ships down at local scales through programs like ‘’ in California. Scaling up such programs will require a concerted effort by conservation organizations, governments and shipping companies,” said co-author Jono Wilson, director of ocean science at the California Chapter of , which helped identify the need for this study and secured its funding. “Whales play a critical role in marine ecosystems. Through this study we have measurable insights into ship-collision hotspots and risk and where we need to focus to make the most impact.”

Co-authors on the study are , a research scientist with the Commonwealth Scientific and Industrial Research Organisation in Australia; research scientists Callie Leiphardt and Rachel Rhodes, and professor , all at the University of California, Santa Barbara; , research ecologist with NOAA’s Southwest Fisheries Science Center; , associate vice president, Anderson Cabot Center for Ocean Life, New England Aquarium; the UW’s , professor of aquatic and fishery sciences, and , a research scientist with the Center for Ecosystem Sentinels; , professor at the Universidade do Vale do Itajaí in Brazil; senior research biologist with the Cascadia Research Collective; data scientist , chief scientist and senior manager with Global Fishing Watch; research scientists Lauren Dares and Chloe Robinson with Ocean Wise; with Oceanswell in Sri Lanka and the University of Western Australia; with Carleton University; biologist with the British Antarctic Survey; , emeritus research scientist with the University of Rhode Island; Russell Leaper with the International Fund for Animal Welfare; Ekaterina Ovsyanikova at the University of Queensland; and Simone Panigada with the in Italy.

The research was funded by The Nature Conservancy, NOAA, the Benioff Ocean Science Laboratory, the National Marine Fisheries Service, Oceankind, Bloomberg Philanthropy, Heritage Expeditions, Ocean Park Hong Kong, National Geographic, NEID Global and the Schmidt Foundation.

For more information, contact Nisi at anisi@uw.edu and Abrahms at abrahms@uw.edu.

are highly social and vocal marine mammals. They use acoustics to navigate, find prey, avoid predators and maintain group cohesion. For Alaska’s critically endangered population, these crucial communications may compete with a cacophony of noise from human activities.

New research from the 91̽��, the National Oceanic and Atmospheric Administration’s Alaska Fisheries Science Center and the Alaska Department of Fish and Game is the first to document the complex vocal repertoire of the Cook Inlet beluga whale population. It is also the first to quantify how ship noise may be masking specific beluga calls in this region.

The , published Nov. 30 in the Journal of the Acoustical Society of America, finds 41 distinct types of calls, of which 18 are unique to this population. It also finds that commercial ship noise completely masks these whales’ most commonly used calls.

“The core critical habitat for these whales is a very noisy area. Commercial shipping, an international airport, military operations and gas and oil exploration are all concentrated there,” said lead author , a doctoral student in the at the 91̽��who did the work in collaboration with NOAA Fisheries’ .

“A fundamental knowledge gap for the Cook Inlet beluga population is how they communicate important information. The first step is to describe their vocal repertoire,” she added. “With that information, we can begin to understand if their communication is impacted by human-caused noise.”

Twenty-one populations of belugas are recognized worldwide, including five distinct populations in Alaska. The geographically and genetically isolated Cook Inlet beluga population is the smallest, recently estimated at just . Cook Inlet beluga whales live exclusively in their namesake waters alongside Anchorage, the state’s largest city and busiest port.

The Cook Inlet beluga whale population was listed as endangered under the Endangered Species Act in 2008. A 2016 recovery plan ranked three threats as the highest level of concern, one being human-caused noise. Commercial shipping is the most prominent noise source within Cook Inlet, particularly in the upper inlet where most of the federally-designated critical habitat is located.

”All of that human-caused noise means the belugas may not hear critical communications from each other, such as predator alarm calls or a mother calling to her calf,” Brewer said.

While all whales are affected by noise, Cook Inlet belugas may be particularly vulnerable to noise as a stressor.

“Cook Inlet is extremely turbid year-round from glacial runoff. It looks like chocolate milk,” Brewer said. “Acoustic communication is extremely important for this population since visibility is so poor. And, unlike other, higher-Arctic beluga populations, this population is non-migratory, so they are exposed to this noise year-round.”

Cook Inlet’s extreme turbidity, dramatic tides, rapid currents and seasonal ice cover make it an extremely challenging place to study belugas. One way scientists can monitor these highly vocal whales is through sound.

The Cook Inlet Beluga Acoustics Program has been deploying bottom-mounted passive acoustic recorders to monitor belugas and human-caused noise since 2008. The study focused on recordings of beluga whale calls from 2018 to 2019.

“Until now, we did not have a quantified measure of masking by ship noise on Cook Inlet beluga communication. We knew this was a potential disturbance mechanism to focus our research efforts, but we were lacking a good understanding of what vocalizations are most important for beluga,” said co-author , a research scientist at the UW-based Cooperative Institute for Climate, Ocean and Ecosystem Studies who manages the acoustics monitoring program. “This study provides the first two steps into this direction: We now have a solid understanding of key vocalizations for this population, and how each ship transit is affecting beluga vocal exchange in the core area of their critical habitat.”

For the new study, scientists analyzed recordings at two critical habitat locations: Susitna River, just outside of Anchorage, and Trading Bay, farther out in the inlet.

They classified beluga vocalizations into three broad categories — whistles, pulsed calls and combined calls — and then further into 41 unique call types.

“I’ve spent thousands of hours listening to this population. Anytime I find a new call type, it’s really exciting,” Brewer said, “Eavesdropping on their world is really fascinating.”

The study found that the Cook Inlet beluga population, like other beluga populations, has a rich and complex repertoire. Vocal repertoire has been documented for eight of the 21 populations of belugas worldwide. Results from this study support the hypothesis that some call types are shared across populations, while others are unique.

Of the 41 types of calls the authors documented in the Cook Inlet population, 18 were not documented in any other population; 16 were documented in some but not all of the previously studied populations; and seven were common to all populations studied so far.

“Differences in vocal repertoire among different beluga populations may be driven by unique evolutionary, environmental or cultural influences,” Brewer said. “The divergence of the Cook Inlet vocal repertoire may be in part due to the population’s long-term geographic and genetic isolation.”

The researchers next looked at how the most commonly-used call types may be masked by human-caused noise. They focused on commercial ship noise, which is the most prominent noise type in Cook Inlet.

Analysis found that all seven of the most commonly-used call types in the Cook Inlet beluga vocal repertoire were partially masked by the time a commercial ship was within about 10 miles (17 kilometers) of the study site. Calls were completely masked when the vessel was closest to the site during the transit through the designated shipping lanes.

Roughly 486 commercial ships use the Port of Alaska annually, with an average of 8-10 ships coming and going per week. It is estimated that each ship passage will mask beluga communication at the study site for 1 hour and 50 minutes on average.

“Our results suggest that every time a commercial vessel transits through the Port of Alaska shipping lanes, Cook Inlet beluga communication could be heavily impacted within their core habitat,” Brewer said.

“Humans are such a visual species. It’s hard for us to comprehend how noisy it is under the surface of the ocean and how much noise impacts marine mammals such as belugas. We hope our findings will lead to further studies to better inform management about these types of human-caused impacts.”

The research was funded by NOAA Fisheries, Hilcorp Alaska LLC, Georgia Aquarium, Shedd Aquarium, the SeaWorld-Busch Gardens Conservation Fund and the H. Mason Keeler Endowed Professorship in Sports Fisheries Management at the UW.

Other co-authors are faculty members and in the 91̽��School of Aquatic and Fishery Sciences; and Tom Gage at the Alaska Department of Fish and Game.

For more information, contact Brewer at arialb@uw.edu or Castellote at manuelcm@uw.edu.

Adapted from a NOAA .

In the Pacific Northwest and British Columbia, scientists have been sounding the alarm about the plight of southern resident orcas. Annual counts show that population numbers, already precarious, have fallen back to mid-1970s levels. Most pregnancies end in miscarriage or death of the newborn. They may not be catching enough food. And many elderly orcas — particularly post-reproductive matriarchs, who are a source of knowledge and help younger generations — have died.

With just 73 individuals left, conservationists and members of the public alike are concerned that southern resident orcas may not survive.

Yet over the same period, the region’s northern resident orcas, who have a similar diet and an overlapping territory, grew steadily in population. Today, there are more than 300 northern resident orcas, leaving scientists wondering why these two similar but distinct populations have had such dissimilar fates over the past half century.

A new study led by scientists at the 91̽�� and reveals that the two populations differ in how they hunt for salmon, their primary and preferred food source. The research, done by an international team of government, academic and nonprofit researchers, March 4 in Behavioral Ecology.

“For northern resident orcas, females were hunting and capturing more prey than males. For southern resident orcas, we found the opposite: The males were doing more hunting and capturing than females,” said lead author , a senior research scientist at the 91̽��’s . “We also found that if their mother was alive, northern resident adult males hunted less, which is consistent with previous work, but we were surprised to see that southern resident adult males hunted more. Adult females in both populations hunted less if they had a calf, but the effect was strongest for southern residents.”

The study’s five years of observational data show that southern resident males catch 152% more salmon per hour than females. In other words, for every two fish a southern female caught, a southern male would catch five. For the growing northern resident population, the trend is flipped: females caught 55% more salmon per hour than males.

This is the first study to track the underwater pursuit, hunting and prey-sharing behaviors of both northern and southern resident orcas. Their findings reveal that, though the two populations overlap significantly in territory and have similar social structures and reproductive behavior, they should not be treated identically for conservation purposes.

“In the past, we’ve made assumptions about these populations and filled in the gaps when designing interventions, particularly to help the southern resident orcas,” said Tennessen, who conducted this study while she was a research scientist with NOAA’s . “But what we found here are strikingly different patterns of behavior with something as critical to survival as foraging. And as we develop management strategies, we really need to consider these populations differently.”

NOAA scientists and an international team of collaborators temporarily tracked the movement, sounds, depth and feeding behaviors of 34 northern and 23 southern resident adult orcas non-invasively from 2009 to 2014 using “Dtags,” cellphone-sized digital devices. Dtags attach via suction to the back of an orca and, for this study, were programmed to fall off hours later and float back to the surface so the researchers could collect them and download their data.

As the name would suggest, northern resident orcas have a more northerly distribution, preferring waters around Vancouver Island and the Queen Charlotte Strait. In contrast, core areas for southern resident orcas hug the southern reaches of Vancouver Island, inland waters surrounding the San Juan Islands, Puget Sound and the Washington coast. Both populations were devastated by the capture of orcas for theme parks, a practice that ended in the 1970s. Since then, northern resident orcas have increased steadily, seeing at least 50% growth since 2001.

Both populations hunt for salmon using echolocation. Adult orcas can dive at least 350 meters — or 1,150 feet — to pursue fish on their own, though they often bring kills to the surface to share with others. Pods travel between the outflows of major rivers and streams in British Columbia and Washington, and have been heavily impacted by dams that have reduced salmon runs. Increased vessel traffic and noise in the Salish Sea — from tourism, recreation and shipping — have also negatively affected these populations, particularly the southern resident orcas, according to Tennessen.

This new study showed that southern residents had fewer successful hunts overall, indicating that they were presumably catching less food. This impact is particularly evident with young mothers.

“In both populations, a mother with a young calf foraged less than other females, possibly due to the risk of leaving the calf temporarily with ‘a babysitter’ — another adult — while she hunts, or because of the time demands of nursing a calf,” said Tennessen. “But for southern resident females, which are more prone to disturbance and stress from vessel traffic, there was an outsized effect: Our study found no instance of a southern resident female with a young calf who successfully carried out a hunt.”

The study also has much to say about the impact of elderly female orcas on their adult sons. Both northern and southern resident orcas are grouped into matriarchal clans, often led by post-reproductive females. They also help feed their adult sons even, as a led by the nonprofit Center for Whale Research showed, at the expense of their own reproductive capacity.

The new study adds complexity to the role of elderly females. Among northern resident orcas, adult males with a living mother hunted less than adult males without a living mother, perhaps because the mother still provides food. But among southern resident orcas, the opposite is true: Adult males with a living mother hunted more.

“These unexpected differences left us scratching our heads. It is possible that southern resident adult males could be sharing with other members of their group, including their mothers, to help out, especially since an adult male’s survival is strongly linked to his mother’s survival,” said Tennessen. “Relatedly, southern resident matriarchs may be leading the group to areas where their adult sons may be able to capture more prey, since healthier sons might be more successful at mating and passing along some of their mothers’ genes. We need more studies to determine what role the presence — or absence, for southern resident orcas — of matriarchs has on male foraging behavior.”

Future studies on the behaviors of northern and southern resident orcas could bring these differences to the surface, as could studies of Alaska resident orca populations, which forage for salmon farther north, where salmon stocks are generally healthier. Such comparative studies can help isolate cause and effect, said Tennessen.

“Understanding how healthy populations behave can provide direction and goals for management of unhealthy populations,” said Tennessen. “Future comparisons to healthy fish-eating orca populations could help us understand whether the divergent behavior we’re seeing in the southern residents is indicative of a population trying to survive.”

Co-authors on the paper are Maria Holt, Bradley Hanson and Candice Emmons with the NOAA Northwest Fisheries Science Center; Brianna Wright and Sheila Thornton with Fisheries and Oceans Canada; Deborah Giles with the 91̽��Friday Harbor Labs; Jeffrey Hogan with the Cascadia Research Collective; and Volker Deecke with the University of Cumbria in the U.K. The research was funded by NOAA, Fisheries and Oceans Canada, the University of Cumbria and the University of British Columbia.

For more information, contact Tennessen at jtenness@uw.edu.

Killer whales are intelligent, adaptive predators, often teaming up to take down larger whales as prey. Continuous reduction in sea ice in the Arctic Ocean is opening areas to increased killer whale dwelling and predation, potentially creating an ecological imbalance.

Underwater microphones placed off the western and northern coasts of Alaska show that killer whales have spent more time than previously recorded in the Arctic, following the decrease in summer sea ice. Brynn Kimber, a researcher from the Cooperative Institute for Climate, Ocean and Ecosystem Studies, the study, “Tracking killer whale movements in the Alaskan Arctic relative to a loss of sea ice,” Dec. 2 in Seattle at a meeting of the Acoustical Society of America.

Killer whales will often travel to different areas to target varieties of prey. In the analysis of acoustic data recorded by four underwater microphones from 2012 to 2019, the Seattle-based team found that killer whales are spending longer in the Arctic Ocean in more recent years, despite risks of ice entrapment there. Their readings indicate this change is directly following the decrease in sea ice in the area.

“It’s not necessarily that killer whales haven’t been reported in these areas before, but that they appear to be remaining in the area for longer periods of time,” said Kimber. “This is likely in response to a longer open-water season.”

The study didn’t set out to focus on the killer whales, or orcas, said Kimber, who was surprised by the results.

“Our work mostly centers on examining the migration patterns of species through the Bering, Chukchi and Beaufort seas, based on acoustic presence or absence. But when looking for other species, like beluga whales, I noticed more and more killer whales in areas where I didn’t expect them. That was what motivated me to take a closer look at our killer whale detections.”

The reduction in sea ice may be opening new hunting opportunities for killer whales, if certain species of prey can no longer use the ice to avoid the highly adaptive predator. For example, the endangered bowhead whale is vulnerable to predation by killer whales, but can hide under sea ice to avoid being circled by orcas. Last fall, another study led by a different CICOES researcher showed the in the Arctic.

This vulnerability, Kimber said, is likely to increase due to longer open-water seasons.

“Although there is high spatial and interannual variability, the September Arctic sea-ice minimum is declining at an average rate of 13% per decade when compared to values from 1981 to 2010,” Kimber said. “Killer whales are being observed in the Chukchi Sea (in the Arctic Ocean) in months that were historically ice covered, and more consistently throughout the summer.”

This study was funded by NOAA, the U.S. Navy and the Interior Department’s Bureau of Ocean Energy Management. Collaborators are , a former 91̽��master’s student who is now at CICOES; at CICOES; and at NOAA.

For more information, contact Kimber at brynn.kimber@noaa.gov.

Adapted from an Acoustical Society of America

Modern cetaceans — which include dolphins, whales and porpoises — are well adapted for aquatic life. They have blubber to insulate and fins to propel and steer. Today’s cetaceans also sport a unique type of nasal passage: It rises at an angle relative to the roof of the mouth — or palate — and exits at the top of the head as a blowhole.

This is an apt adaptation for an air-breathing animal at home in the water. Yet as embryos, the cetacean nasal passage starts out in a position more typical of mammals: parallel to the palate and exiting at the tip of the snout, or rostrum. Cetacean experts have long puzzled over how the nasal passage switches during embryonic and fetal development from a palate-parallel pathway to an angled orientation terminating in a blowhole.

“The shift in orientation and position of the nasal passage in cetaceans is a developmental process that’s unlike any other mammal,” said , a postdoctoral researcher at the 91̽�� School of Dentistry. “It’s an interesting question to see what parts remain connected, what parts shift orientation and how might they work together through a developmental process to bring about this change.”

New research by Roston and , a professor of biology at Duke University, is shedding light on this process. By measuring anatomical details of embryos and fetuses of pantropical spotted dolphins, they determined the key anatomical changes that flip the orientation of the nasal passage up. Their findings, July 19 in the Journal of Anatomy, are an integrative model for this developmental transition for cetaceans.

“We discovered that there are three phases of growth, primarily in the head, that can explain how the nasal passage shifts in orientation and position,” said lead author Roston, who began this study as a doctoral student at Duke.

The three phases of growth are:

1. Initially parallel, the roof of the mouth and the nasal passage become separated as the area between them grows into a triangular shape. This phase begins during embryonic development after the face starts forming, which, for the pantropical spotted dolphin, is in the first two months after fertilization.
2. The snout grows longer at an angle to the nasal passage, further separating the nostrils from the tip of the snout. This phase begins later in fetal development and may continue even after birth.
3. The skull folds backward, and the head and body become more aligned. This rotates the nasal passage up so that it becomes nearly vertical relative to the body axis. This phase begins in late embryonic development and continues through fetal development.

“While the nose moves to the top of the head, many of the important angular changes are actually in the bottom, or base, of the skull. That’s not necessarily something you’d expect to find!” said Roston.

The three phases of growth do not unfold in a step-by-step process, but instead overlap with each other temporally, Roston said. They represent distinct developmental transformations that, put together, shift the nasal passage to the top of the head.

Roston and Roth developed this model using anatomical data obtained by photographs and CT scans of 21 embryonic and fetal pantropical spotted dolphin specimens held by the Smithsonian Institution’s National Museum of Natural History and the Natural History Museum of Los Angeles County. The specimens represented a wide range of embryonic and fetal development.

For comparison, they obtained data from eight fin whale fetuses, also at the National Museum of Natural History, and found significant differences between them and the pantropical spotted dolphin. In fin whales, the skull folded in a region in the back of the skull, near where the skull joins with the vertebral column. In the pantropical spotted dolphin, the folding is centered near the middle of the skull.

The model Roston and Roth developed could inform how scientists view cetacean evolution. These creatures began to evolve from a four-legged, land-dwelling mammalian ancestor, which had a nasal passage parallel to the palate, more than 50 million years ago. As cetaceans evolved, the blowhole gradually migrated from the tip of the snout to the back of the snout, and then gradually up to the top of the skull.

In addition, the two species represent different branches of the cetacean family tree that diverged more than 30 million years ago. Dolphins — along with porpoises, orcas, sperm whales and beaked whales — are odontocetes, commonly known as toothed whales. Fin whales are from a group called the baleen whales, named for their distinct feeding apparatus.

“I’m struck by two interesting discoveries that emerged from this work,” said Roth. “Although they both develop blowholes, there are key differences between a baleen and a toothed whale in how they reorient their nasal passages during development. Moreover, surprisingly, accompanying the processes of developing upwardly oriented nostrils there are profound changes within the braincase.”

In the future, examining more species from both lineages could indicate whether all baleen and toothed whales differ in this manner, Roston said.

“This model gives us a hypothesis for the developmental steps that had to occur to make that anatomical transformation happen, and will serve as a point of comparison for additional studies of growth and development in whales, dolphins and porpoises,” said Roston.

The research was funded by Duke University. Roston has also been supported by the National Institutes of Health.

For more information, contact Roston at rroston@uw.edu and Roth at vlroth@duke.edu.

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

As we try to take care of ourselves and each other during the COVID-19 pandemic, why not also check on our friends in the ocean as well? — an online tool launched by scientists at the University of California, Santa Barbara, the 91̽�� and other partner institutions — allows users to detect and better protect these endangered creatures in the Santa Barbara Channel in near-real time.

Whale Safe is a mapping and analysis tool that displays data in near real-time to help prevent ships from running into whales. It is the result of three years of work among the Benioff Ocean Initiative at UC Santa Barbara, the UW, the Woods Hole Oceanographic Institution, the Scripps Institution of Oceanography, Texas A&M University at Galveston, UC Santa Cruz and the National Oceanic and Atmospheric Administration’s Southwest Fisheries Science Center.

, a 91̽��assistant professor of biology, led efforts to model whale behavior in the channel for Whale Safe.

“The goal is to put this technology into the hands of managers, mariners and the public to help protect these animals from ship strikes and other threats,” said Abrahms.

“Unfortunately, 2018 and 2019 were the worst years on record for fatal whale-ship collisions off the coast of California,” said Morgan Visalli, a scientist with the Benioff Ocean Initiative and leader of the Whale Safe project. “We hope that data from the Whale Safe system can help to reverse that trend.”

Whales often feed, migrate, rest, mate and socialize in coastal areas. Aggregations of up to 30 blue whales — the largest animals that have ever lived — were observed last month in the Santa Barbara Channel.

Whale migration routes overlap with some of the world’s busiest shipping lanes, with cargo vessels moving through the Santa Barbara Channel to and from the ports of Los Angeles and Long Beach. Shipping vessels can reach more than 10 times the length of an adult blue whale. They tower so high above the surface of the ocean that whale spouts are difficult for crews to detect, let alone slow down for or avoid. Researchers estimate that more than 80 endangered blue, humpback and fin whales are killed by vessel collisions every year just off the West Coast.

In 2007 NOAA implemented a voluntary speed reduction program for all large vessels transiting through whale habitats around California’s Channel Islands. The limit, which is 10 knots or 11.5 miles per hour, reduces the number of fatal collisions by up to 80% to 90%, according to research.

While more shipping companies are enrolling in the voluntary program, in 2019 more than half of ship transits in the channel still exceeded 10 knots. The researchers hope that, by alerting users to the presence of whales in the area, Whale Safe will help slow more ships along this stretch of California coast.

“One of our goals is to provide real-time whale presence data that will help ships know when to slow down,” Visalli said. “In 2019, only 44% of the shipping industry followed the voluntary speed limit — we’d like to see the cooperation rate get closer to 100%.”

Whale Safe combines several technologies: an underwater acoustic system that automatically detects whale calls; near real-time forecasts of whale feeding grounds; and whale sightings by scientists reported through a mobile app. These sources of information are combined into a daily “Whale Presence Rating” on the Whale Safe website — an indicator that describes the likelihood of whales from “low” to “very high.”

“It provides a streamlined daily assessment of whale activity in the channel,” Visalli said. “No one wants to hit a whale. No one wants to see coastal commerce interrupted. We hope that the data delivered by the new technology will provide ship captains with the information they need to protect whales while ensuring efficient maritime commerce.”

The acoustic system consists of a hydrophone dropped into the Santa Barbara Channel that detects sounds in the water and uses AI to identify blue, humpback and fin whales in near real-time. A surface buoy then transmits the data to scientists at Texas A&M Galveston for review and confirmation mere hours after the first detection.

Abrahms and colleagues at UC Santa Cruz and NOAA created the model that forecasts potential whale activity in feeding grounds using oceanographic data such as temperature and ocean currents. Those forecasts can inform ship crews of their chances of encountering whales along their course.

“Predictive models like this give us a clue for what lies ahead, much like a daily weather forecast,” said Abrahms. “We’re harnessing the best and most current data to understand what habitats whales use in the ocean, and therefore where whales are most likely to be as their habitats shift on a daily basis.”

The model has applications beyond Whale Safe.

“Our model also helps us plan for new challenges to whale conservation as ocean conditions change,” said Abrahms. “If the ocean does something extreme, like form a heat wave, it is likely to affect where and when whales will show up. That information is important for managers and mariners to be able to respond adaptively.”

The final piece of information behind Whale Safe comes from observations by community scientists on board whale-watching and tourism boats, logged via a mobile app from the Channel Islands Naturalist Corps, a joint program by NOAA and the Channel Islands National Park.

Whale Safe also collects information about vessels in the channel, including speed. This information is turned by the Whale Safe tool into “report cards” for the ships and their companies, rating their cooperation with voluntary speed limits in important whale habitat.

The researchers hope Whale Safe will lead to benefits beyond saving endangered whales. When cargo ships slow down, they typically emit less CO2, generate less noise pollution and release fewer nitrogen oxide emissions. In time, it may also form the basis of tool kits to protect whales and marine mammals in other major shipping areas — including Puget Sound.

For more information, contact Abrahms at abrahms@uw.edu.

Adapted from a by UC Santa Barbara.

This is the only population of blue whales known to have recovered from whaling – blue whales as a species having been hunted nearly to extinction.

Blue whales – nearly 100 feet in length and weighing 190 tons as adults – are the largest animals on earth. And they are the heaviest ever, weighing more than twice as much as the largest known dinosaur, the Argentinosaurus. They are an icon of the conservation movement and many people want to minimize harm to them, according to , 91̽��assistant professor of aquatic and fishery sciences.

            “The recovery of California blue whales from whaling demonstrates the ability of blue whale populations to rebuild under careful management and conservation measures,” said , a 91̽��doctoral student in quantitative ecology and resource management and lead author of a on the subject posted online Sept. 5 by the journal Marine Mammal Science. Branch and , a 91̽��professor of aquatic and fisheries sciences, are co-authors.

California blue whales ­ are at their most visible while at feeding grounds 20 to 30 miles off the California coast, but are actually found along the eastern side of the Pacific Ocean from the equator up into the Gulf of Alaska.

Today they number about 2,200, according to monitoring by other research groups. That’s likely 97 percent of the historical level according to the model the co-authors used. That may seem to some a surprisingly low number of whales, Monnahan said, but not when considering how many California blue whales were caught. According to Monnahan, Branch and another set of co-authors published earlier this summer in PLOS ONE, approximately 3,400 California blue whales were caught between 1905 and 1971.

“Considering the 3,400 caught in comparison to the 346,000 caught near Antarctica gives an idea how much smaller the population of California blue whales was likely to have been,” Branch said.

The catches of blue whales from the North Pacific were unknown until scientists – in particular Yulia Ivashchenko of Southern Cross University in Australia – put on their detective caps and teased out numbers from Russian whaling archives that once were classified as secret but are now public. The numbers Russian whalers had publicly reported at one time were incomplete and inaccurate ­– something that was admitted in the late 1990s – but there wasn’t access to the real numbers until recently.

For the work published in PLOS ONE, the scientists then used acoustic calls produced by the whales to separate – for the first time – the catches taken from the California population from those whales taken in the western Northern Pacific near Japan and Russia. The two populations are generally accepted by the scientific community as being different. Places where acoustic data indicated one group or the other is present were matched with whaling catches.

In the subsequent Marine Mammal Science paper just out, the catches were among the key pieces of information used to model the size of the California blue whale population over time – a model previously used by other groups to estimate populations of hundreds of fish and various other whale species.

The population returning to near its historical level explains the slowdown in population growth, noted in recent years, better than the idea of ship strikes, the scientists said.

There are likely at least 11 blue whales struck a year along the U.S. West Coast, other groups have determined, which is above the “potential biological removal” of 3.1 whales per year allowed by the U.S. Marine Mammal Protection Act.

The new findings says there could be an 11-fold increase in vessels before there is a 50 percent chance that the population will drop below what is considered “depleted” by regulators.

“Even accepting our results that the current level of ship strikes is not going to cause overall population declines, there is still going to be ongoing concern that we don’t want these whales killed by ships,” Branch said.

Without ship strikes as a big factor holding the population back – and no other readily apparent human-caused reason (although noise, chemical pollution and interactions with fisheries may impact them) – it is even more likely that the population is growing more slowly because whale numbers are reaching the habitat limit, something called the carrying capacity.

“We think the California population has reached the capacity of what the system can take as far as blue whales,” Branch said.

“Our findings aren’t meant to deprive California blue whales of protections that they need going forward,” Monnahan said. “California blue whales are recovering because we took actions to stop catches and start monitoring. If we hadn’t, the population might have been pushed to near extinction – an unfortunate fate suffered by other blue whale populations.”

“It’s a conservation success story,” Monnahan said.

Funding for students working on the research in Branch’s lab comes through the Joint Institute for the Study of the Atmosphere and Ocean, a collaboration between the National Oceanic and Atmospheric Administration and UW.

###

For more information:
–Branch, tbranch@uw.edu
–Monnahan, monnahc@uw.edu

(NOTE: Monnahan is traveling Sept. 6-20)

Blue Whale News,

Journal articles referenced in this release:
–“”
Marine Mammal Science
Co-authors: Cole Monnahan, Trevor Branch and André Punt

–“”
PLOS One
June 3, 2014
Co-authors: Cole Monnahan, Trevor Branch, Kathleen Stafford, Yulia Ivashchenko, Erin Oleson

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.

###

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.

A carcass that washed up on a Seattle-area beach this spring provided a reminder that sleek fin whales, nicknamed “greyhounds of the sea,” are vulnerable to collision when they strike fast-moving ships. Knowing their swimming behaviors could help vessels avoid the animals. Understanding where and what they eat could also help support the fin whale’s slowly rebounding populations.

91̽�� oceanographers are addressing such questions using a growing number of seafloor seismometers, devices that record vibrations. A series of three papers published this winter in the interprets whale calls found in earthquake sensor data, an inexpensive and non-invasive way to monitor the whales. The studies are the first to match whale calls with fine-scale swimming behavior, providing new hints at the animals’ movement and communication patterns.

The research began a decade ago as a project to monitor tremors on the Juan de Fuca Ridge, a seismically active zone more than a mile deep off the Washington coast. That was the first time 91̽��researchers had collected an entire year’s worth of seafloor seismic data.

“Over the winter months we recorded a lot of earthquakes, but we also had an awful lot of fin-whale calls,” said principal investigator , a 91̽��professor of oceanography. At first the fin whale calls, which at 17 to 35 vibrations per second overlap with the seismic data, “were kind of just a nuisance,” he said.

In 2008 Wilcock got funding from the Office of Naval Research to study the previously discarded whale calls.

, a 91̽��doctoral student in oceanography, compared the calls recorded by eight different seismometers. Previous studies have done this for just two or three animals at a time, but the 91̽��group automated the work to analyze more than 300,000 whale calls.

The method is similar to how a smartphone’s GPS measures a person’s location by comparing paths to different satellites. Researchers looked at the fin whale’s call at the eight seismometers to calculate a position. That technique let them follow the animal’s path through the instrument grid and within 10 miles of its boundaries.

Soule created 154 individual fin whale paths and discovered three categories of vocalizing whales that swam south in winter and early spring of 2003. He also found a category of rogue whales that traveled north in the early fall, moving faster than the other groups while emitting a slightly higher-pitched call.

https://soundcloud.com/uw-today/finwhale-and-earthquake

“One idea is that these are juvenile males that don’t have any reason to head south for the breeding season,” Soule said. “We can’t say for sure because so little is known about fin whales. To give you an idea, people don’t even know how or why they make their sound.”