For almost a decade, the Washington Sea Grant Crab Team has been surveilling the advance of the invasive European green crab. In 2015, the team was formed to engage citizen scientists in a search for the first signs of an invasion into Puget Sound, with the first documented trap of a green crab taking place a year later in August 2016. They have now been found in more than 30 trapping sites throughout the northern half of Puget Sound and Hood Canal.
This is the primary method of maintaining some control of the population of invasive crabs: intense trapping. It works to limit damage to native species, sensitive habitats and commercial shellfish operations.
University of Washington
An invasive European green crab.
Sean McDonald, a University of Washington researcher and one of the organizers of the Crab Team, said in a new story by Salish Sea Currents that the involvement of volunteers has been critical to the surveillance program. Monitoring efforts need to be maintained over time to be meaningful, he noted, and ongoing government funding for more costly professional field work cannot be assured.
His own research, which began as green crabs were reaching Washington’s outer coast, involved studying the relationship between green crabs and the Northwest’s native crabs.
*Story adapted from the Salish Sea Currents article written by Christopher Dunagan, Puget Sound Institute.
Lisa Watkins, Washington Sea Grant
Emily Grason (left), marine ecologist with the Washington Sea Grant Crab Team and volunteers set European green crab traps at Harper Estuary in South Central Puget Sound.
Fullbright Scholar, Science contributor, freshwater biologist. These are some of the ways to describe Aashna Sharma, who is currently working with Dr. Julian Olden at SAFS as part of her two-year postdoctoral fellowship. From the foothills of the Himalayas in India, Aashna was recently inspired by the Past as Prologue feature in Science that highlights how different scientists from around the world are shaped by their family and background, and submitted a piece herself. It was published on July 31, 2025 in Vol 389, Issue 6759 of Science, and we caught up with Aashna to find out more about it.
How did it come about, you writing for Science as part of their Past as Prologue feature?
Aashna Sharma
Aashna Sharma with my mother during her doctoral days.
Past as Prologue is an occasional feature in Science that highlights scientists from around the world, focusing on how their family and sociocultural background shaped them into the scientists they are today. It’s surprising how often, in celebrating a scientist’s work, we overlook the human side—the stories, influences, and personal journeys that spark curiosity and shape ideas. In recent years, there’s been a welcome shift toward celebrating these narratives, especially the “pillars of strength” behind scientists—the loved ones without whom many discoveries might never have happened.
When I first read a Past as Prologue piece, I was so moved that I went on to read all the others—there are only about seven published so far. I remember thinking, I want to write the next one. As someone who deeply values acknowledging the people who support and sustain a scientific career, I felt compelled to tell my own story. Even knowing the feature is rare and highly competitive, I knew I had to try.
What inspired you specifically to become a freshwater biologist, with a focus on India’s freshwater megafauna?
I’m a trained freshwater biologist and have spent much of the past decade working in Himalayan freshwater ecosystems. My doctoral research focused on interactions between native and invasive trout, and during that time I collaborated with colleagues studying everything from insects to mammals. But freshwater systems have always held my heart.
Arvind Sharma
The Dhauladhar range of Himalayas as seen from Aashna’s house.
For my current Fulbright project, I turned my focus to large-bodied freshwater species—India’s freshwater megafauna. These species act as umbrella species, helping protect many others that share their habitats. They are also ecosystem engineers, shaping the environments and biodiversity around them in unique ways. Globally, freshwater megafauna receive far less attention than other groups, and in India, they had never been discussed collectively before. I felt it was time to change that. Our rivers hold extraordinary species—from crocodilians, turtles, and tortoises to swamp deer, river dolphins, and even sharks. My project examines how land-use and climate change affect them now and into the future.
I think my fascination began in childhood, watching the immaculate headwaters of mountain streams. As scientists, we all feel connected to many ecosystems, but one inevitably pulls us in more strongly. For me, that will always be freshwater. Still, I love exploring terrestrial flora and fauna just as much, and I’m particularly drawn to understanding the links between them. Forest–stream connectivity is one area I hope to explore further in the future.
When thinking about your mother and her passion for science, did you always know you wanted to pursue science, inspired by her?
I did. She has always been my pillar of motivation and strength. Her dedication, discipline, and the way she combined a scientific and spiritual approach to nature made her my childhood star. With a bachelor’s degree in natural sciences, she seemed to embody the path I somehow knew I would follow. She answered even my simplest questions in the most engaging ways—sparking curiosity and inspiring me to ask more.
Aashna Sharma
Aashna on one of the rivers in her home state, at the Great Himalayan National Park, Himachal Pradesh, India.
One of the fondest memories of her nurturing my scientific curiosity is when she taught me about the inflorescence of Bauhinia variegata, a medium-sized tree native to South and Southeast Asia. In the mid-elevations of the Himalaya where I grew up, we called it kachnar. Its delicate orchid-like blooms appear in folk songs, but for me, they were part of everyday life. The tree bloomed abundantly in our backyard, and I often climbed its slender branches to collect buds and blossoms, which my mother would turn into traditional pickles and dips. I also remember the white flowers of Citrus maxima, the largest citrus fruit, visited by honeybees—early glimpses into the intricate connections in nature.
As I grew older, these moments crystallized into something more than fond memories. They were signposts, guiding me toward science and reassuring me, even then, that I was already on the right path.
What project are you working on currently?
My two-year postdoctoral fellowship is funded by the Fulbright Program, and as a Fulbright-Kalam Climate Scholar, I’m leading an independent project on India’s freshwater megafauna, with Dr. Olden serving as my host mentor.
Aashna Sharma
Macroinvertebrate sampling in trans Himalaya.
What brought you to SAFS to continue your scientific journey? Do you see any similarities here in the things that inspired you when you were young to pursue science?
I had originally developed my Fulbright project with a mentor at another university in the US, but I ended up at SAFS at the University of Washington at the last moment—a turn of events that has worked out wonderfully, as I’ve been able to learn so much here.
Through SAFS and the Fulbright community, I’ve gained a deeper cross-cultural perspective, met incredible colleagues, and had the chance to understand not only new scientific approaches but also the people and culture of the United States.
In many ways, SAFS reflects the qualities that first inspired me to pursue science: discipline, curiosity, and a commitment to digging deeper into the natural world’s mysteries. It’s a place where people are serious about their science yet passionate about exploring and understanding the intricate connections that shape our ecosystems.
Aashna Sharma
Aashna Sharma spreads awareness among forest staff about benthic macroinvertebrates in Himalayan streams.
Last year, we spoke with SAFS undergrad, Michael Han, about receiving the NOAA Hollings Scholarship and where this would take him over the next year. This summer, Michael has split his time between NOAA’s HQ in Silver Spring, Maryland and NOAA’s Aircraft Operations Center (AOC) in Lakeland, Florida. His internship has been focused on NOAA’s Hurricane Hunters, aircraft which fly into the world’s worst weather to collect data which assists forecasters in making accurate predictions during hurricanes, and helps hurricane researchers achieve a better understanding of storm processes. Read about Michael’s summer internship below.
Michael Han
Michael sits in the NOAA Twin Otter.
The main project I was working on with NOAA’s Office of Marine and Aviation Operations (OMAO) was a visualization of Hurricane Hunter aircraft flying through Hurricane Milton. Milton was the strongest Atlantic storm last year in 2024, exceeding Cat 5 speeds and being one of the most intense storms ever found over the Gulf. NOAA OMAO was heavily involved in forecasting and researching it, conducting 10+ research flights from October 6-10, 2024. I retrieved flight track coordinates and plotted them with the help of ArcGIS and Python, then overlaid a sheet of satellite images of liquid and solid precipitation to show the hurricane itself. This was a visualization that was created specifically for the Science on a Sphere, which is a large globe model present in Smithsonians and many other museums across the country.
My time was split between headquarters at Silver Spring, MD and NOAA’s Aircraft Operations Center (AOC) in Lakeland, Florida. Although NOAA’s aircraft can be all over the world at any given time, all 10 are ultimately stationed at AOC. This includes four DHC-6 Twin Otters, three Beechcraft King Airs, two WP-3Ds, and one Gulfstream 4. Being there allowed me to take video footage with a 360 camera of all the different aircraft and splice segments into the visualization for a more complete view of the mission. AOC was definitely the highlight of my internship since I was able to get out of the office and have some hands-on learning with the planes. However, my favorite part was getting to talk to all the NOAA Corps officers and ask them about their career paths, the planes they fly, and how they contribute to the scientific process.
Besides my main Hollings project, I also shadowed my mentors around, attended a whole bunch of meetings, and worked on some fun side tasks such as mapping out NOAA’s flights on the Texas floods or gathering info on the P-3’s scientific instrumentation.
View from above…
…taken in a NOAA Twin Otter.
The pictures above show the NOAA Twin Otter in transit from Hagerstown, MD to Lakeland, FL. NOAA operates four DHC-6 Twin Otters which are part of the light aircraft fleet. They stay busy 365 days a year conducting scientific research on missions such as air chemistry, LIDAR, coastal mapping, and marine mammal surveys. When this picture was taken, the aircraft (N46RF) was on its way back to AOC after completing a month long study on ozone concentrations near Baltimore, which involved sampling the atmosphere for certain compounds that contribute to the formation of ozone. The research was done in predetermined grids east of the city as the prevailing winds during the study were westerly.
My main role while flying in the Otter as a student pilot was to get some on-the-job training from the NOAA Corps officers flying the plane up front. I learned about the locations and functions of the various instruments present in the cockpit and how NOAA flights communicate with Air Traffic Control (ATC) when operating research missions.
Gulfstream 4.
WP-3D Orion.
The two photos above are taken in the heavy plane hangar at AOC! The NOAA fleet currently includes three heavy aircraft and seven light planes. The heavy aircraft visible in these pictures are the Gulfstream 4 (left) and the WP-3D Orion (right). These planes are the backbone of NOAA’s hurricane hunting fleet and provide the data researchers need to accurately forecast storms. The P-3 is a large, turboprop aircraft tasked to fly straight into hurricanes at an altitude of 8-10,000 feet. The cone shaped object mounted on the back end of the plane is a tail-doppler radar (TDR) which is used to vertically scan the storm. This is combined with a horizontally scanning radar mounted on the belly to create a 3D cross section of the hurricane, which is sent to the National Hurricane Center, real time, to be immediately incorporated into forecast models.
The G4, nicknamed Gonzo, is a heavily modified business jet also outfitted with a tail doppler radar (TDR) and various scientific instrumentation. Both planes also have the capability to launch dropsondes and unmanned systems such as drones from launch tubes. Dropsondes are small cylinders released from the underside of the aircraft and record metrics such as temperature and humidity as they fall, and the data is processed by a special dropsonde operator in the back. Unmanned systems provide some similar capabilities but are able to remain in the air for longer periods and return more readings.
Michael Han
Into the eye of the storm: the long list of hurricanes and countries this plane has flown through are marked on its side.
Decals or victory marks can be seen in the photo above, showing all the hurricanes this P-3 has flown through, along with the countries it has operated in! The marks face left (counterclockwise) for Northern Hemisphere missions and vice versa. Hurricane Milton, which I worked on, is visible in the bottom left corner.
Time for preflight checks!
The preflight process involves a mission brief where the objectives are laid out and roles of everyone on board are made clear. The flight plan is discussed and the pilots go over their physical and emotional wellbeing. Once that’s completed they’re out to the aircraft, and pictured above is the pilots conducting an exterior walkaround of the plane. This entails checking the tire and brake systems, looking for cracks in the structure, and ensuring the flight controls have full freedom of movement.
Seattle’s new Waterfront Park development — a decade and a half and $800 million in the making — includes a rebuilt seawall. It works to reconnect the city to the glittering water of Puget Sound. Baby salmon can be seen swimming past, shining silver glitter amid waving fronds of bull kelp. Right overhead, people walk over glass blocks set in the concrete of the seawall to allow light to pass into the waters of Elliott Bay.
The $330 million replacement seawall was completed in 2017 and has helped accommodate salmon and other aquatic life. Glass blocks and grating in the seawall are a way to be a bit more fish-friendly. Shallowing up the bottom and adding complexity and unevenness to the seawall also provides a place for sea life to grow, rest and feed. It’s a step up, ecologically, from the deep, dark, concrete wall that used to be there, said Jason Toft, principal research scientist at the Wetland Ecosystem Team at the School of Aquatic and Fishery Sciences at the University of Washington. Researchers from this team have been instrumental in the restoration work and continued monitoring since the new seawall.
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.
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.
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 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.
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.
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.
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.
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).
Understanding what a species eats – and how that changes over time – not only gives us a window into the lives of wild animals, but also gives us the power to be responsible stewards of their ecosystems.
Genetic metabarcoding is changing the way we look at diet and foraging ecology in whales. With each new sample, we gain new insight into the feeding behavior of these enigmatic species. Learn more about how the Whale And Dolphin Ecology Lab (WADE), led by SAFS Assistant Professor Amy Van Cise, is using genetic metabarcoding to understand and conserve southern resident killer whales in the Salish Sea.
