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Beluga whales’ calls may get drowned out by shipping noise in Alaska’s Cook Inlet – Alaska Native News

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Beluga whales’ calls may get drowned out by shipping noise in Alaska’s Cook Inlet – Alaska Native News


Beluga whales 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 Cook Inlet beluga population, these crucial communications may compete with a cacophony of noise from human activities.

New research from the University of Washington, 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 study, 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.

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“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 Arial Brewer, a doctoral student in the School of Aquatic and Fishery Sciences at the UW who did the work in collaboration with NOAA Fisheries’ Alaska Fisheries Science Center.

“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 331 individuals. Cook Inlet beluga whales live exclusively in their namesake waters alongside Anchorage, the state’s largest city and busiest port.

Map of Cook Inlet, Alaska, with red pins where underwater recordings used for this study. Stripes show Cook Inlet beluga whale critical habitat, and the blue line shows designated Port of Alaska commercial shipping lanes.Kim Shelden/NOAA Fisheries
Map of Cook Inlet, Alaska, with red pins where underwater recordings used for this study. Stripes show Cook Inlet beluga whale critical habitat, and the blue line shows designated Port of Alaska commercial shipping lanes.Kim Shelden/NOAA Fisheries

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.

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“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 Manuel Castellote, 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.

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

Cook Inlet beluga mother and calf in turbid, or cloudy, waters.Paul Wade/NOAA Fisheries
Cook Inlet beluga mother and calf in turbid, or cloudy, waters.Paul Wade/NOAA Fisheries

“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.

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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.

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Other co-authors are faculty members Amy van Cise and Andrew Berdahl in the UW 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 feature story.

U of W

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Alaska

Heat spreads across Alaska with no widespread rain in sight

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Heat spreads across Alaska with no widespread rain in sight


ANCHORAGE, Alaska (KTUU) – Tuesday was the fifth day in a row with above-average temperatures in Anchorage, and the 10th consecutive day without any measurable rainfall. This warm and dry trend will continue through the end of June, and likely into the first week of July.

High pressure is centered over the state. With the upper-level winds forced north, most of Alaska will stay storm-free.

The same cannot be said for the Aleutians or across the Bering Sea. An area of low pressure is spreading north, bringing high winds, rain, and a high surf to the northern Kuskokwim Bay coast. This area should be prepared for water levels to rise three to six feet above normal high tide. Wind gusts of 45 to 50 mph are also likely.

The Aleutians will also stay cool Wednesday, but high temperatures will climb back to the upper 60s and low 70s across Southcentral, mid- to upper 60s across Southeast, to the 80s across the Interior, and even to the 60s on the Slope.

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Anchorage has already reached 75 degrees or above three times this month. We’ve only seen three days over 75 degrees in June six times in recorded history. The overall average temperature for June is only about half a degree above what is normal but is about 2 degrees above June to date of 2023. This month’s rainfall is also significantly lower than what most of Anchorage experienced last June, which brought 17 days with measurable precipitation, while this year, we’ve seen just four days with rain.

The number of active wildfires in the state is up to 222 as of Tuesday evening, and 22 of those are new in the past 24 hours. Fortunately, lighting activity was lower on Tuesday, with fewer than 1,000 strikes recorded. More than 5,000 lightning strikes were recorded in Alaska on Monday, and more than 6,000 were tallied on Sunday.

With high fire danger continuing, use extra caution to keep from adding any additional human-caused fires. Burn permits are suspended in the Mat-Su and Interior. Open fires are prohibited in Anchorage.



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Report identifies opportunities restoring access to SE Alaska fisheries – The Cordova Times

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Report identifies opportunities restoring access to SE Alaska fisheries – The Cordova Times


Floating oyster growing system by Erik O’Brien at Larsen Bay, Kodiak. Photo courtesy of Erik O’Brien

A new report compiled by the Alaska Sustainable Fisheries Trust (ASFT) in Sitka finds that Southeast Alaska communities are losing access to fisheries, but also identifies opportunities for implementing new ways to restore such access for the region. 

“Based on what we heard from the dozens of community members who participated in our survey, it is clear that Southeast’s communities, particularly Indigenous communities, are losing access to fisheries and their future access remains uncertain,” said Linda Behnken, ASFT board president. “However, it is also clear that we have some real opportunities when it comes to designing and implementing new tools to help restore this access and ensure that local needs are being factored into larger discussions and decisions concerning Southeast’s economy.” 

The report, released June 18, compiles findings of a regional survey ASFT distributed to area residents this spring in collaboration with the Sustainable Southeast Partnership (SSP) — proposing ways to address issues. The report was funded by the Southeast Conference through the U.S. Department of Agriculture’s Southeast Alaska Sustainability Strategy initiative.  

ASFT said the goal is to assist local communities by providing data and information for future dialogues and community development planning, increasing awareness and encouraging more funds for fishery access-related projects. Participating communities included Angoon, Craig, Haines, Kake, Ketchikan, Klawock, Klukwan, Juneau, Sitka, Wrangell, and Yakutat.  

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Responses from these communities universally identified the fisheries as a crucial element of Southeast Alaska’s culture and economy moving forward. Respondents expressed concern about their ability to access and have a sustainable livelihood from local fisheries through traditional harvesting, commercial or recreational fishing. 

Respondents’ key concerns included the changing climate and environment of Southeast Alaska and a sense of unpredictability for the future of marine resources. They expressed a lack of confidence that current scientific approaches to fishery management will be adequate in light of significant changes affecting the region and its resources due to climate change. 

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The report also discussed existing systems of governance that challenge access to fishery resources, challenges with limited access management at the state and federal levels and loss of community infrastructure such as processors, fish buyers, cold storage, marine services and/or transportation often initiated with the trend in outmigration of fishery access in remote communities. 

Many participating area residents said the utmost priority is protection and perpetuation of a traditional way of life, with commercial fishing considered secondary, as a tool to bridge the traditional and cash economies. 

They discussed the rapid growth of tourism in Southeast Alaska as something feeding competition and tensions between local-commercial and traditional-use harvesters and non-local harvesters in the sportfish sector. 

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The report included recommendations for building more equitable and accessible fisheries in Southeast Alaska, including incorporating climate change variability and unpredictability into fishery management tools to facilitate fishery access and to ensure that other industries, including tourism and mariculture, do not further limit fishery access.   

Recommendations also included establishing regional entities to hold quota/permits (such as regional Community Quota Entities and regional fisheries trusts) and more investment in community infrastructure. 
Behnken said that ASFT was grateful to everyone who shared their thoughts on this complex topic. 

“We hope that this report will uplift their voices and be a chance for the public, policy makers, and others to better understand some of the challenges that many Southeast residents are facing so that we can collectively find solutions and build a resilient and vibrant future for Southeast’s fisheries and communities,” she said. 

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Hot and dry conditions lead to increasing wildfire danger across Alaska

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Hot and dry conditions lead to increasing wildfire danger across Alaska


ANCHORAGE, Alaska (KTUU) – Summer weather continues to build in across the state, as a ridge is greatly influencing the weather across Mainland Alaska. Temperatures have been warming into the 70s and 80s through the Interior, while Southcentral has seen highs in the 60s and the 70s. This stretch of warm weather will remain through the week, accompanied by possibly thunderstorm development.

While hot and dry conditions have been building, the Aleutians are dealing with wet and breezy weather. This comes as a low near the Aleutians continues to lift to the north. Expect widespread rain through parts of this region, with the heaviest rain near the Pribilof Islands. Winds will gust anywhere from 30 to 65 mph. As the rain pushes to the northeast, it will run into ridging and quickly taper off into Wednesday. Some light rain showers look possible through parts of Southwest Alaska tomorrow morning, before the rain comes to an end.

Outside of the Aleutians and areas with thunderstorm formation, Alaska will remain on the drier side this week. While the ridge isn’t strong enough to cap thunderstorm development, it will prevent its widespread activity. It’s likely isolated to scattered storms will persist through the Interior and in Southcentral Alaska. A quick reminder that burn permits have been suspended in the Mat-Su Valley and Fairbanks due to the hot and dry conditions.

Any storms across Southcentral today will primarily impact western parts of the Matanuska Valley, the foothills of the Talkeetna Mountains and into the Copper River Basin. Storm motion will be to the north, so Anchorage and surrounding locations will largely stay dry. A rogue thunderstorm can’t be ruled out for the Kenai, but any precipitation will come in the form of spotty to isolated morning showers.

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This hot and dry weather pattern continues through the end of June. Here in Southcentral, the weekend is once again shaping up to warm into the 70s.

Have a wonderful and safe Tuesday!



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