Climate change and communication go hand-in-hand for PNW Climate Ambassadors

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We’re living in a digital age, where the ability to find information (or even at times misinformation) is instant wherever you are in the world. This comes at the same time we’re at a critical juncture for climate research, where studying our changing world is more important now than ever. For Amirah Casey, a graduate student at SAFS, she knows that communication is vital to make impactful changes, and so applying for the Pacific Northwest (PNW) Climate Ambassadors program was a no-brainer.

The PNW Climate Ambassadors program at the University of Washington trains UW graduate students studying climate change, its impacts, or potential responses to effectively engage with various sectors of the public. Comprised of a cohort of 10 graduate students from different colleges across UW, researching topics from chemical oceanography and the impacts of urbanization on salmon, to environmental public policy and the evolution of ancient ecosystems, the program prepares students to develop presentations on a topic related to their climate science interest and expertise.

A group of students part of the PNW Climate Ambassadors program, pose for a photo.
Miriam Bertram, PCC
Participants in the pilot PNW Climate Ambassador Workshop in April 2025.

The PNW Climate Ambassadors program is a collaboration between the Program on Climate Change (PCC), the Washington State Climate Office (WASCO) and the UW College of the Environment Communications Team.

Amirah is a student among the first cohort to be PNW Climate Ambassadors. “It feels really exciting to be a part of this pilot program. I knew it would be a great opportunity to get more involved in the climate community and get necessary training to advance my career,” she said. “When applying, reading that we would be trained to “effectively engage with various sectors of the public” aligned with my goal of practicing this skill as much as possible while in graduate school. Plus, when it comes to climate change, we all know that it can be a sticky subject, so learning to communicate about it effectively is very important.”

The first step towards being a PNW Climate Ambassador was to undertake climate communication training from the WASCO and the Climate Impacts Group (CIG). Students got to practice some of the techniques they learned with an exercise at the end of the training. “Next, we were split into teams give our interests and expertise, and we designed presentations about a give topic that we added to a slide library,” Amirah shared. These presentations can be requested by the public by visiting the PNW Climate Ambassadors website. “Once we get a request through and accept, we use the slide database and other provided materials to tailor a presentation to the specific audience requesting it. Before presenting, we practice our talk with other ambassadors, one of our mentors from CIG, WASCO or PCC, or another expert in the area we are presenting on,” she added. Initial training was completed in May 2025, and although Amirah hasn’t yet had a presentation request, she’s excited for when the opportunity does arise.

A screenshot of a presentation slide.
Amirah Casey
Amirah worked on the presentation titled: Impacts of Climate Change on Water, Droughts, and Flooding in the Pacific Northwest.

Amirah’s focus area for her PNW Climate Ambassador presentation is water, droughts, and flooding. The slides discuss sea level rise, precipitation, and other issues in as much detail as possible while also keeping it concise and to the point. This is an essential skill for those engaged in climate research: how to share the importance of your work to the world, while also ensuring it’s engaging, impactful, and understandable for those with a non-science background. “My group also homed in on making the slides visually appealing and easy to read, while not being text heavy,” Amirah said. “In this presentation, I got to talk about things within my expertise, but also some things outside of it, like flooding. This was a great learning experience, and I got very valuable feedback from my fellow ambassadors and CIG mentor, Guillaume Mauger.”

Amirah Casey (l) and former Gov. Jay Inslee (r) speak at an event.
Amirah Casey had the chance to speak with former Governor Jay Inslee at the Climate Solutions annual dinner.

Among the highlights of the program so far for Amirah has been receiving climate communication training, especially today in a time of uncertainty in climate policy and the spread of misinformation. “As someone who wants a career bridging science and policy, it will be essential for me to continue to develop these skills. There’s a lot of misinformation out there about climate impacts, as well as some distrust in science, and so having people who are trained to communicate about these issues is critical to get across clear and accurate information,” she said. “I am grateful to this program for giving me a chance to build on my climate communicate skills, and to my advisor, Dr. Mark Scheuerell, who has also been helping me with these techniques.”

After joining the PNW Climate Ambassadors program, Amirah felt inspired to get more involved in climate solutions and be present in as many climate spaces as possible. One of the opportunities that arose for her was volunteering at the Climate Solutions annual dinner, held in May 2025. “The organization is focused on, you guessed it, climate solutions! I helped them set up the dinner in downtown Seattle and checked in guests, including former Governor Jay Inslee,” Amirah shared. “I made sure to talk to him about what is going on with NOAA and USGS, which are the organizations that my committee members work for, especially because they are currently under fire for lack of a better term. I also thanked him for his policies while he was in office that were supportive of science, education, and recovering and protecting Washington state wildlife.” While she was volunteering, Amirah was recruited by PNW Climate Week to help out with event planning and logistics, which took place in Seattle from 16-25 July 2025. PNW Climate Week involves community-powered events that shine a spotlight on the Pacific Northwest’s role in climate leadership and innovation.

In a shifting ocean environment, what are the impacts on Pacific oysters?

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Seeking to understand the impacts of environmental stressors on Pacific oysters is the driving force behind a years-long research project involving scientists from the University of Washington and NOAA, and in collaboration with the oyster industry. A new paper about the project was made available online in Aquaculture on June 17, 2025. Critical in aquaculture, Pacific oysters are the dominant oyster species grown on the US West Coast, with the industry in the Pacific Northwest alone valued at over $270 million a year.

Oyster farm viewed from above, close to the shoreline.
Craig Norrie
An oyster farm viewed from the sky.

But this study drills down into the species one step further, looking into the differential performance of diploid, mated triploid, and induced triploid Pacific oysters under different environmental conditions. Compared to diploid oysters, triploid oysters have an additional set of chromosomes, they grow faster and are functionally sterile. As a result, they comprise a large proportion of oysters grown both in the Pacific Northwest and worldwide. Recent studies have found that the waters off the West Coast were acidifying faster than anywhere else in the world, and so studying the impact of changing oceans on oysters—and how it affects those with different chromosome numbers—can assist the shellfish aquaculture industry in making more informed decisions about their species portfolio.

Racks and cages pictured at low tide that are used on oyster farms.
Craig Norrie
The racks and cages used to grow oysters.

The team of researchers, led by Craig Norrie from the UW School of Aquatic and Fishery Sciences (SAFS), sought to understand how stressors such as temperature, dissolved oxygen (DO), and pCO2 , impacted Pacific oysters across a 4-week period. The study focused on whole organism physiological responses—growth, mortality and respiration—for genetically related juvenile diploid, chemically induced triploid, and mated triploid Pacific oysters.

What researchers found was an overall high survival in all groups across a broad range of temperature and DO levels. “They are a pretty hardy species, so to an extent you can see why survival was reasonably high in the temperature experiment—these guys are grown from Baja California up to Alaska so can tolerate a broad array of conditions,” Norrie said. “However, farmers report that over the summer period when its warmer, triploids generally die more—the high survival in our study could be due to the fact that they were younger oysters.”

For DO, this was a more surprising result for researchers. “It was reasonably surprising that they survived so well under different dissolved oxygen levels—everyone needs to breathe, right? How did they manage to hold their breath for so long?” Norrie asked. “Again, this could be because they grow in such a broad range of conditions.”

pCO2  was a different story. At mid pCO2, between 1450 and 1700 μatm (microatmospheres, a unit of pressure), mated triploids had lower survival than the other groups in the study, which suggests that production method or genetic background may contribute to their resilience or susceptibility to stress. “Oysters can adapt to local conditions over a few generations, and this can make them better equipped to deal with the conditions that they are likely to encounter naturally,” Norrie said. And this means in the case of these oysters which didn’t perform so well under low pH conditions, a lack of exposure in their family history to may mean they haven’t developed resilience to this environmental stressor. However, the team found that when pCO2 reached extreme levels of 2100 μatm, all oysters in the study died. This suggests that if conditions become extreme enough, there is the possibility that all oysters, regardless of ploidy or production method, will be impacted.

Four tanks in a laboratory.
Craig Norrie
The experimental tanks used for the project which examined the responses of Pacific oysters to environmental stressors.

As a culturally and economically important industry, developing new insights into how aquaculture will be impacted by changing oceans is critical. Considering the stressors that will be placed on species such as Pacific oysters will allow those working in aquaculture to make informed decisions on which type of oysters to select to ensure the future resilience of the industry.

The research team included Joth Davis from Baywater Shellfish, Shallin Busch and Paul McElhany from NOAA, and research scientists, professors, and undergraduate students from the University of Washington: Dereck Cordova (undergraduate student in the IBIS program), Hailey Dockery (undergraduate researcher), Craig Norrie (research scientist and project lead), and Jacqueline Padilla-Gamiño (SAFS professor).

Corals, contaminants, and climate change

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Bleaching. This complicated and foreboding term now lurks around every conversation about coral reefs. Impacted heavily by climate change and associated warming oceans, coral reefs experience bleaching when the algae that live in their tissues and contribute vitally to their growth are expelled, causing the corals to lose their color, and possibly their lives.

Closely related to anemones and jellyfish, corals can obtain algae from the environment and put them in their tissues. “Corals live like a little diaphanous greenhouse, where the algae are safe and consume the waste products from coral. In exchange, the algae give oxygen, sugars, and other nutrients back to the coral animal,” Callum Backstrom, a PhD student at SAFS, describes. The mutualism between coral and algae allows corals, otherwise diminutive, gelatinous animals, to make the massive, multi-ton skeletal structures composing reefs. Home to about 25% of all marine life and hosting up to half of all marine fish at some point in their life cycle, coral reefs are incredibly important for humans too, reducing up to 85% of wave height and storm energy on the coastlines they border.

A person is pictured diving underwater to view a coral reef, wearing a snorkeling mask.
Mike McCollough
Callum dives to collect corals in Kahekili Beach Park, Maui, to assess the extent of heavy metal contamination from the Lahaina Fires of 2023. He uses a titanium axe and rubber mallet to break and remove coral fragments for metal toxicology analysis. Collection under permit of the Department of Land and Natural Resources, Hawaiʻi.

A member of Jacqueline Padilla-Gamiño’s lab group, Callum is interested in the resilience of certain corals to bleaching. “I’m asking questions like why are some corals more resilient? And for the ones that do survive, how could coral reproduction be compromised after a bleaching event?” Callum shared. A primary cause of bleaching is ocean warming, which causes the algae to go into “overdrive,” producing toxic forms of oxygen that in turn stress the coral into expelling their primary food source. Bleached corals may resorb their reproductive cells for nutrition and otherwise forego reproduction altogether to survive starvation until they can regain their photosynthetic algae.

Callum stands hip-deep in water, with corals visible on the shallow seafloor in front of him. In the background, the coastline with palm trees is visible.
Katherine Lasdin
The Padilla-Gamiño lab has been growing coral colonies in Kāneʻohe Bay for almost a decade, providing a diverse pool of corals to use for experiments and to measure growth rates over time. Here, Callum is inspecting the lab’s coral racks, including colonies that he is monitoring to determine for the first time whether male and female corals grow and respond to bleaching events differently.

More resilient corals that resist bleaching may contain strains of heat-tolerant algae, but, as Callum explains, there are issues associated with this: “When oceans are cooler and times are good, these resilient types of algae are not generally the best partners for the coral. They aren’t as efficient, or don’t provide as much energy to the coral as less resilient algal strains and therefore can cause the coral to be outcompeted by other coral colonies in their environment.” Another way that more resilient corals combat bleaching is by increasing their rate of feeding on zooplankton and detritus from the water column; however, more feeding could mean these corals are prone to consume more pollutants, such as microplastics and heavy metals, in the marine environment.

The effects of these pollutants are a specific area of interest for Callum: do bleached corals accumulate more pollutants from a less photosynthetic, more feeding-driven diet, and could these acquired pollutants damage the health or reproductive success of bleached corals well after recovery of their symbiotic algae?

Some pollutants, like microplastics, are synthetically produced by humans and therefore have a clear origin as environmental contaminants. One difficulty faced when asking questions about elemental contaminants like metals is that many metals are used in low concentrations as essential trace nutrients for healthy coral function. But most studies on this topic focus on vertebrates, and very little is known about contaminants in organisms without a backbone, such as corals. “So, a key piece of this puzzle is to find out what the normal concentrations are for corals, what kind of contaminants are building up and at what level, and is this happening when they’re stressed and eating more?” Callum said.

Callum over a large blue tub which holds water and a number of corals. He is holding a coral in both of his hands while smiling into the camera. Other blue tubs can be seen behind him.
Jacqueline Padilla-Gamiño
Callum displays a live colony of rice coral (Montipora capitata) at the Hawaiʻi Institute of Marine Biology in Kāneʻohe Bay, Hawaiʻi. By collecting the egg-sperm bundles released by these hermaphroditic coral colonies on nights around the new moon in the summer months, Callum can compare the metal toxicology of the corals’ egg and sperm cells, and of the algae cells packed into the eggs, to the metal levels of the adult parent and its algal cells.

The breakdown in the symbiosis between corals and their algae helps to answer this question. Callum has extensively studied the mutualistic exchange of resources between corals and their algae – last year, he published his work investigating the role of photosynthesis in mesophotic corals from deep, almost pitch-black depths of the ocean in the Proceedings of the Royal Society.

Two small corals side by side on top of a blue tub - the one of the left is a brown color, and the one on the right is bleached white.
Callum Backstrom
In controlled experiments in onshore tanks with waterflow from the reef, Callum simulates bleaching events on clonal fragments of coral colonies to monitor how trace metal nutrients are exchanged and lost during the bleaching process. A healthy clone with its brown algal symbionts is shown on the left, while a bleached clonal fragment (white) is shown on the right for comparison. In some experiments, Callum further compares how bleached fragments change their feeding rates and preferences for microplastic pollutants relative to healthy fragments.

This gave him a basis to hypothesize about how bleaching events can show us what is essential to that mutualism. “When a coral undergoes a bleaching event and dumps out all its algae, when it gets them back, the metals found in the newer algal cells could be the ones important for normal cell function, as opposed to lifelong contaminants. I have found that algal cells packed inside coral eggs prior to reproduction have different, often lower metal concentrations than those in the adult coral, which could corroborate a baseline level of “healthy,” essential trace levels of these metals. Everything else above these baselines, or that does not get transferred to the offspring, then has a much more compelling basis to be called a contaminant,” Callum explains. An example of an elevated metal that Callum has seen in the eggs of coral is arsenic. Used in herbicides in Hawaii’s agriculture, atomic pollutants such as arsenic don’t degrade, meaning arsenic released into the environment 100 years ago remains in the system. “And now we might be seeing it work its way through corals and other marine organisms,” Callum shares.

To study these issues, Callum conducts his fieldwork at the Hawaiʻi Institute of Marine Biology on Moku O Loʻe (Coconut Island), off Oʻahu. There, for projects spanning the last three years, Callum has collected and grown corals on the reef, stained corals to track their growth rates, and even brought them to large tanks on the shoreline for months at a time to simulate bleaching events, run feeding experiments, and collect coral eggs and sperm during spawning events. His work in the summer of 2024 investigating the effects of the Lahaina fires of summer 2023 on corals in Maui concluded various studies of the bioaccumulation of metals and microplastics in corals, which will serve as the foundation of his PhD dissertation.

Three people stand in the water, holding snorkeling gear, with blue skies and white fluffy clouds visible in the background.
Allyson L.T. Ijima.
Callum with members of the University of Hawai’i’s coral collection team in west Maui, undergraduate Jasmine Alip (l) and Ph.D. student Justin Berg (r).

Callum hopes that his work studying bleaching and pollution events in coral reefs will help us understand and predict the needs of corals into the future. More immediately, his pollution-oriented research will help isolate specific metals to be targeted by remediation efforts across Oʻahu and Maui, especially in the wake of the Lahaina fires. For example, certain plants like Chinese Brake Fern could be integrated into coastal zones to remove arsenic from contaminated soils that is leaching into Hawaiian reefs. However, by characterizing the exchange of trace metal nutrients between corals and their symbiotic algae, and the breakdown of this exchange during bleaching, Callum can further identify metals that could help boost coral resilience. Emerging studies are testing the potential for trace metal seeding to boost thermal resilience in marine algal populations; Callum believes his work can help these applications expand to corals as well.

In addition to various SAFS course guest lectures and department symposia, Callum has been featured as a speaker at the International Coral Reef Symposium in Bremen, Germany in 2022, the Western Society of Naturalists in Monterey Bay, CA, and at a microplastics research workshop at the Seattle Aquarium, both in 2023. For his talk describing his heavy metals research at the annual meeting of the Society of Integrative and Comparative Biology in Seattle in 2024, he earned the Mary Rice Award for Best Student Presentation. Callum mentors six undergraduate students across various departments, who have been instrumental in his research toward his PhD dissertation. He also leads weekly lab meetings with his undergraduate research students to discuss topical papers and/or share experiences and ideas related to their work as a team. These meetings have also provided opportunities for feedback among coral team students as they communicate their findings across venues throughout the college, such as undergraduate research symposia. This year, Callum has been recognized as one of the Husky 100 for his PhD research and undergraduate mentorship at the UW.

Most days, you can find Callum tinkering with corals in the Fishery Sciences Building or preparing live-organism demonstrations in the class laboratories of the Fisheries Teaching & Research Building. You can catch him and his undergraduate team displaying live invertebrates and plastic pollution-catching devices at the upcoming Aquatic Sciences Open House on 17 May!

Callum stands smiling into the camera for his Husky 100 portrait.
University of Washington
Congratulations to Callum Backstrom, one of UW’s 2025 Husky 100.

Bringing to life the story of Pacific salmon and their recovery challenges

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In a StoryMap bringing to life the challenges faced by Pacific salmon, SAFS graduate student, Amirah Casey, dives into the role of urban stormwater runoff and climate change in hindering salmon recovery.

Pacific salmon and Steelhead are vital to many parts of life in the Pacific Northwest, and across western North America. From recreational and commercial fisheries that benefit humans, to providing a food source for birds and marine mammals, while also being central to the cultures of Indigenous Peoples, these species are integral in this part of the world. Historically low abundances led to research which revealed a unique threat to them: polluted stormwater runoff and the presence of the chemical 6PPD-q, which comes from when the chemical 6PPD in vehicle tires reacts ozone in the air.

Two fish in a shallow river.
Samantha-Lynn Martinez
Some Pacific salmon, like coho, are facing historically low abundance, due to stressors such as climate change and urban stormwater runoff. Pictured are coho and chum salmon.

“I have always been interested in how humans impact the environment, and my interest in urbanization and climate change really blossomed in high school,” Amirah shared. “My jumpstart into research began when I took the first ever class as part of the Marine and Coastal Science cohort at Western Washington University (WWU), taught by Dr. Jim Cooper. He taught us about POP’s (persistent organic pollutants) and I was soon working in his lab with chemicals like PCBs and PBDEs.”

After joining the SAFS graduate program, Amirah became a member of the Applied Ecology Lab, advised by Dr. Mark Scheuerell, and reached out to the program manager of the NOAA Ecotox team—Dr. Nat Scholz—to see if there were any opportunities to collaborate. “I told him my two biggest interests were the effects of urbanization and climate change on our natural systems and how I wanted to be a part of the solution. That is when he said: “Oh yeah, you’re one of us” and we have been working together ever since,” Amirah said.

Amirah’s collaborators at the NOAA Northwest Fisheries Science Center (NWFSC) Ecotoxicology Program had an old StoryMap on their website and the EPA website, dating from before 6PPD-q was discovered. Amirah decided she would take on the project of revamping the StoryMap with updated science and engaging elements to share more widely about the stressors that Pacific salmon are facing. “The impacts of stormwater runoff on species like Coho salmon are undeniable,” Amirah said. “Up to 90% mortalities in urban watersheds after storm events is completely unsustainable if there is any hope of recovering these species, and that’s why I became so interested in how these two stressors (urbanization and climate change) impact Pacific salmon.”

A graphic showing how the chemical 6PPD, used in vehicles tires, ends up waterways. The graphic depicts a car and stormwater draining into a river.
Samantha-Lynn Martinez
Amirah Casey is using illustrations such as these graphic designs created by recent UW graduate, Samantha-Lynn Martinez, to demonstrate how chemicals end up in waterways and impact salmon.

Two big elements were new in Amirah’s version of the StoryMap. One was updated information, compiled over decades of research on this topic by the NOAA Ecotox team. “My role in this project was to sort through all the folders of images and videos collected by NOAA and select which would tell the best story, and likewise go through linked resources such as articles, YouTube videos and peer-reviewed literature that would support readers looking for more information,” Amirah said. “As someone who has worked on stormwater for so many years, the insights and narratives provided by Nat Scholz were invaluable in telling this story.”

The second new element were original graphics, videos and photographs, created and taken by Samantha-Lynn Martinez, a recent graduate of the UW Marine Biology program. “I met with Samantha-Lynn during a SEAS outreach event, and she had shared some of her work with salmon and stormwater, and a lightbulb went off in my head,” Amirah shared. “I really wanted to be able to work with her to take images and videos, and create graphics for the StoryMap—and get paid for her work—so that’s when I applied for the Future Rivers support funding and was able to hire Samantha-Lynn for her amazing graphic design and photography.”

Check out the easily accessible and engaging StoryMap, “Pacific Salmon at a Crossroads”, to learn more about the story of urban stormwater runoff and climate change, and to dive in to more resources and open-source papers on the subject.

Explore the StoryMap

Surveys show full scale of massive die-off of common murres following the ‘warm blob’ in the Pacific Ocean

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A University of Washington citizen science program — which trains coastal residents to search local beaches and document dead birds — has contributed to a new study, led by federal scientists, documenting the devastating effect of warming waters on common murres in Alaska.

From tropics to temperate: The shifting breeding ranges of seabirds amid climate change

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Foxes are migrating northward, frogs are climbing higher into the mountains, and walruses are hauling out closer to shore. Across the globe, species are shifting their ranges in response to environmental changes driven by climate change. However, seabirds face distinct challenges in adapting to these shifts. Unlike many species, seabirds rely on both suitable terrestrial and marine habitats for survival. While they can follow their prey as it moves northward in the ocean, successful reproduction depends on finding quality terrestrial breeding grounds that overlap with these changing marine environments. 

The California Channel Islands may serve as a critical climate refuge for seabirds. Situated at the convergence of the cool, nutrient-rich California Current and the warmer, more tropical Southern California Countercurrent, the archipelago offers a uniquely diverse oceanographic environment. This position supports a diverse mix of northern and southern breeding seabirds found nowhere else in the world. Channel Islands National Park, which spans four of the islands, provides an added layer of protection for these vulnerable species. At least 16 seabird species currently breed on the islands, and the park is estimated to provide habitat for 99% of the breeding seabirds in Southern California.

Amelia DuVall, a PhD candidate at the University of Washington’s School of Aquatic and Fishery Sciences (SAFS) and a member of the Washington Cooperative Fish and Wildlife Research Unit, is a scientist in the world of seabirds. In September 2024, she and her colleagues published a paper in Western North American Naturalist reporting on the breeding range expansion of two pantropical seabird species—the Brown Booby (Sula leucogaster) and the Blue-footed Booby (S. nebouxii). Previously, the northernmost breeding locations for both species were in Mexico. Brown Boobies are found in tropical oceans across the globe, and Blue-footed Boobies along the west coast of the Americas from Peru to Baja California, Mexico. However, both now breed at Sutil Island, a small rocky island off Santa Barbara Island in Channel Islands National Park, marking the first confirmed breeding records for Sula species in the continental United States.

A bird is pictured from the side/underside view, flying over the ocean. The bird has a white head and underside, with black/brown wings.
David Pereksta
Adult Brown Booby in flight near Sutil Island.

Sutil Island is a steep small (13-acre) island that is closed to the public and rarely accessed by researchers. Due to limited access, researchers have tracked the gradual arrival of boobies by observing the island from a boat with binoculars, from nearby Santa Barbara Island, or through aerial photographs taken by helicopter. Brown Boobies were first observed on Sutil Island in October 2013, with breeding confirmed four years later, in October 2017. The number of nest sites attended by adults or containing chicks grew from four in 2017 to 31 in 2022, and the total number of birds at the colony increased to 164 by September 2021. Blue-footed Boobies were first sighted in August 2018, with breeding confirmed two years later when a hybrid Brown Booby/Blue-footed Booby chick was documented.

A map with scale, showing the southern coast of California, stretching down to Baja California, with markings for the sites of birds.
The northern portion of Brown Booby (BRBO) and Blue-footed Booby (BFBO) breeding ranges within the eastern Pacific Ocean, with the previous northernmost breeding locations of both species denoted with stars. Inset includes detail of the new breeding colony at Sutil Island, off Santa Barbara Island in the California Channel Islands, USA.

So, what’s driving the northward range expansion of these seabird species? A key factor is rising sea surface temperatures. Warmer waters affect the physiological and ecological tolerances of seabird prey, causing shifts in prey distribution toward cooler northern waters. In essence, as the fish move, the seabirds follow. The 2014-2016 marine heatwave was particularly significant, as it triggered a northward shift in the distribution of larval Pacific sardines and anchovies, with the highest concentrations of larval fish in the northern California Current observed in 2015 and 2016—levels not seen since the 1990s. The collapse of the sardine fishery between 2009-2013 in the northern Gulf of California—the likely source population for these seabirds—may also have contributed to the expansion of their breeding range. As climate change progresses, the northward shift of these crucial prey species is expected to continue over the next century, with sightings of Sula species becoming more frequent as far north as Washington State.

The other researchers involved in the study are Jim A. Howard, California Institute of Environmental Studies, David M. Pereksta, Bureau of Ocean Energy Management Pacific OCS Region, David M. Mazurkiewicz, Channel Islands National Park, Adam J. Searcy, Creosote Biological, Phillip J. Capitolo, Institute of Marine Sciences, University of California, Santa Cruz, and Tamara M. Russell, Scripps Institution of Oceanography, University of California, San Diego.

READ THE PAPER PUBLISHED IN WESTERN NORTH AMERICAN NATURALIST

Climate change and Pacific oysters: what are the impacts of heat stress?

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What brings a biology student into the Roberts Lab at SAFS? Eric Essington, a senior in the UW Biology program, has been working on his independent research project in the Roberts Lab for the past year, looking into a familiar hard-shelled mollusk: the oyster. Why? To simulate temperature changes associated with climate change and explore the impact on oysters.

A group of Pacific oysters used for Eric’s experiment.

Looking specifically at the Pacific oyster, a commercially important species in Washington where the majority are farmed, one of the big issues facing the aquaculture sector are large summer die-offs due to warmer temperatures and other environmental stressors. Reaching up to 10 inches in length, Pacific oysters are also key filter feeders, meaning they clean the water as they eat.

Conducting his research at the Jamestown Point Whitney Shellfish Hatchery, which lies on the shores of Dabob Bay and Hood Canal on the eastern side of the Olympic Peninsula, Eric’s experiment started off with the arrival of more than 200 adult oysters, along 120 each of juvenile (one year old oysters), seed (young oysters large enough to be transplanted) and spat (at the life stage when the oyster has permanently attached to a surface).

The group of researchers preparing to simulate the acute thermal stress event, where the oysters were immersed in 32ºC water.

With the oysters divided into two groups, the experiment consisted of one group living in a tank mirroring their natural aquatic environment at 17ºC, and the other in a tank designed to simulate erratic and harsh heat stress associated with climate change. With an increase in temperature of 2ºC every hour until the water hits a stress-inducing 26ºC, this was maintained for six hours each day for seven weeks. A secondary, mechanical stress event was also implemented for adults and juveniles, designed to mimic the physical disturbance of tumbling in currents and encounters with predators and debris that oysters may face in their natural habitats.

The final stage of Eric’s experiment simulated an acute thermal stress event, where the oysters were immersed in 32ºC water for 30 minutes, following by the mechanical stress simulation, followed by tissue sampling for RNA and DNA analysis. The aim? To gauge the physiological response of oysters to compounded stressors.

Conducting this experiment with oysters at different life stages, Eric found that heat stress at the spat stage resulted in tolerance to a secondary stress that corresponds to increased growth. The energy trade-off from developing a resistance to temperature changes during stress events means they have more energy available for growth later on. This result could have real-world application for hatcheries, who could harden young oysters in a similar way before releasing them to grow, so that they provide improved yields during the summer months.

Recently presenting his research at the Mary Gates Research Symposium, Eric shares that next steps in this experiment would be to explore why increased growth and decreased transcription was only significant in the youngest life stage of an oyster.

Interested in more details about Eric’s work? Check out his lab notebook

Witnessing one of nature’s most impressive migrations: a summer with the Alaska Salmon Program

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Nestled among a set of glacial lakes in the Wood River system is where scientists with the Alaska Salmon Program spend their summers. From students just beginning their research journeys in aquatic sciences, to seasoned field technicians and faculty, the camps based on Lake Aleknagik and Lake Nerka are the temporary home for both scientists and the fish that they are studying: Pacific salmon.

Niamh Owen-McLaughlin
Tens of millions of sockeye salmon return to Alaska’s freshwater systems each year.

Five different types of Pacific salmon return to the western Alaskan watersheds of the Nushugak River system each summer, but the sockeye salmon is the predominant one in the Wood River system, where the Alaska Salmon Program conducts much of its research. Changing from a silver color in the marine environment to a startling red when they return to freshwater systems, sockeye salmon are one of nature’s most impressive migrations. Year after year, tens of millions of sockeye salmon return to the freshwater systems in which they were born, to continue the cycle of spawning for the next generation of fish.

Niamh Owen-McLaughlin
Researchers collect data on salmon abundance, sex ratios, spatial distributions across spawning areas, species differentiation, and ages of returning salmon from otoliths (the ear stones of fish).

The Alaska Salmon Program at UW, formerly known as the Fisheries Research Institute (FRI), has been running since the 1940s and continues to this day to deliver the latest insights into Alaska and one of the world’s important aquatic ecosystems and fisheries. It’s also a program that trains the next generation of fishery and aquatic scientists in an immersive, hands-on, and real-world environment that undergoes a huge transformation each year. To date, hundreds of students have visited the field camps in Alaska, with many going on to work in fields such as fishery and wildlife management, environmental education and academia.

Niamh Owen-McLaughlin
Hundreds of students have visited the field camps in Alaska since the 1940s, learning essential skills for fishery and aquatic scientists.

So, what does an average day with the Alaska Salmon Program look like? Collecting data on salmon abundance, sex ratios, spatial distributions across spawning areas, species differentiation, and ages of returning salmon from otoliths are just some of the things feeding into the Alaska Salmon Program’s long-term monitoring program. Otoliths, the ear stones of fish which provide information on size and age, are taken from dead salmon which have completed spawning or have been killed by bears.

Niamh Owen-McLaughlin
Otoliths, the ear stones of fish which provide information on size and age, are taken from dead salmon which have completed spawning or have been killed by bears.

Another area of research is limnology, which is the study of inland aquatic ecosystems, involving researchers going out on skiffs to various points around the lakes to collect samples including temperature and presence of aquatic organisms like zooplankton, which are the primary food for juvenile sockeye salmon that rear in the lakes before migrating to the ocean.

Niamh Owen-McLaughlin
The long-term monitoring data gives insight into the impact of climate change on these ecosystems and how the fish are responding as they return to the streams to spawn.

All of this data feeds into the Alaska Salmon Program’s long-term monitoring program that tracks abundance and the impact of wider issues like climate change on these ecosystems. All the different streams and lakes in these watersheds react differently to climate, as do the fish in them – from migrating fish like sockeye salmon to resident fish like rainbow trout and grayling. The data generated from long-term monitoring efforts and research therefore give insight into the impact of climate change on these ecosystems and how the fish are responding when they travel up the streams to spawn.

Another key part of the work of the Alaska Salmon Program is its pre-season forecasts provided to the fishing industry that operates out of Bristol Bay. Forecasts on fish runs and age/weight of fish is important for the management of commercial fisheries as the forecasts allow managers and fishers to fine-tune their operational plans for the following season A new development in this work is providing an earlier pre-season forecast as the industry begins planning for the next season’s operations, even as the current season is winding down.

Watch Part 1 of our mini series with the Alaska Salmon Program

Watch Part 2 of our mini series with the Alaska Salmon Program

 

Did you know, Aleknagik means ‘Wrong Way’ in Yupik? The Wood River is a major tributary of the Nushagak River, joining the main river near the coast at what is present-day Dillingham. In pre-historic times, if residents traveling inland from the coast reached Lake Aleknagik via Wood River, they knew they’d gone the wrong way if they had actually intended to navigate up the mainstem of the Nushagak.