Category: GRANITE

The Gray Whales of Sitka Sound

Natalie Chazal, PhD Candidate, OSU Department of Fisheries, Wildlife, and Conservation Sciences, GEMM Lab

Sitka (Tlingit: Sheet’ká), Alaska is a wonderful town, tucked along the western coast of Baranof Island in Southeast Alaska. With one side of the sound framed by cascading mountains and the other by Mount Edgecumbe volcano, this place has a striking beauty with a very distinctive ecology.

Figure 1. Map of Sitka Sound from Starr et al. 2011.

One of the many islands within the sound is Japonski Island, home to the University of Alaska Southeast (UAS) Sitka Campus Whale Lab, led by Dr. Lauren Wild and Dr. Ellen Chenoweth. The Whale Lab, previously led by Professor emeritus Jan Straley, has been monitoring whales for over 40 years. Through a myriad of data collection methods including photographic-identification (photo-ID), tissue samples, acoustic recordings, and accelerometry tags, the lab investigates whale diets, genetics, population dynamics, human-cetacean interaction, movement, and foraging ecology. With such rich datasets and, more importantly, deep ties to the community, the Whale Lab has long been a leader in understanding the whales of Sitka Sound.

Since around 2019, the Whale Lab has noted a marked increase in gray whales coming into the sound to take advantage of the pulsed resource of the spring herring spawn (from fewer than 20 individuals prior to 2019, to more than 150 individuals since 2019). Gray whales have been opportunistically monitored by the Whale Lab since the 1990s. To get a better understanding of the dynamic use of Sitka sound by these whales, the Whale Lab initiated a dedicated research program. Through collaboration with the Whale Lab, we in the GEMM Lab hope to learn more about the Sitka gray whales and the health and ecology of gray whales along the Oregon coast through comparative studies. But first, let’s get acquainted with the herring spawn!

The Herring Spawn

Pacific herring (Tlingit: Yaaw) are small schooling forage fish that spend most of their lives offshore, moving inshore each spring to spawn (NOAA Fisheries). However, Sitka Sound is unique because some herring overwinter locally in deeper trenches on both the southeast and western sides of the sound, helping to sustain a productive ecosystem year-round. As they approach the spawning season, the herring stay deeper in the canyons, waiting for sea surface temperatures to reach a threshold suitable for spawning (Harley et al. 2024). Once conditions are right, they move farther up in the water column and further into Sitka Sound. This draws in predators like humpback whales that forage on the adult herring using behaviors like bubble-net feeding.

Humpbacks aren’t the only ones targeting the adult herring. In Southeast Alaska, herring are harvested by humans in the spring for their roe using purse seines. Fishery openings are timed based on abundance, distribution, size, population structure, and past trends. The goal of the Sitka sac roe fishery is to sustainably harvest adults with the highest quality roe, meaning that specific fishing areas will open when pre-spawning fish are abundant and areas will close or be reduced when spawning begins (Dupuis et al. 2026). Sitka supports a robust herring fishery and is one of the last remaining sac roe fisheries in the state of Alaska (ADFG Herring Timeline).

Herring are broadcast spawners and synchronize the timing of the eggs (roe) release and the sperm (milt). The release of milt is what causes the water to turn that characteristic light turquoise color. Spawning occurs continuously for roughly two weeks, though timing varies by year. The eggs are incredibly adhesive, sticking to each other, kelp, seagrass, rocks, and even settling onto mats over the benthos.

Figure 2. (Left) Eelgrass beds at low tide with herring eggs, (Center) closer image showing more detail of herring eggs attached to eelgrass and (Right) Willa Johnson holding kelp blades with attached herring eggs | Photo Credit: Willa Johnson (left, center) & Dr. Lauren Wild (right)

The huge quantity of eggs settles to the bottom and form mats that provide a rich nutrient source for many organisms. Another important harvest occurs at this point in the spawn: the cultural, traditional, and subsistence harvest of the eggs. Tlingit people have harvested herring eggs as an important food source and cultural resource for over 10,000 years. One of the Tlinigt clans, Kiks.ádi, is even named for them, with the women of the clan being called the herring ladies. The Tlingit and Haida method of gathering herring eggs involves placing hemlock boughs in the water, allowing herring to spawn on the branches, which are then collected (Thornton 2019; Theriault Boots 2026). Any eggs or branches not needed are returned to the ocean to contribute back to the ecosystem, so no food is wasted.

A single fertilized herring egg takes about two weeks to develop and hatch. After hatching, the herring larvae remain in the nearshore waters for a couple of weeks to months, though ocean conditions may advect some out of the sound. Due to the sheer size of the broadcast spawning event, there are inevitably eggs that go unfertilized or don’t survive to hatching. As a result, multiple developmental stages (hatched larvae, live developing eggs, and dead eggs) can coexist in the same area. These stages may differ in their distribution, caloric value, and availability, creating a complex and dynamic resource landscape for predators.

Figure 3. (Left) undeveloped herring eggs attached to Fucus distichus and (Right) herring eggs that have developed eyes or “eyed out” | Photo Credit: Willa Johnson (left) & Dr. Lauren Wild (right)

Bringing in the Whales

Now that we have a sense of the significance and timing of the herring spawn in Sitka Sound, let’s bring in the gray whales! Unlike humpback whales, which target adult herring, gray whales are sticking around for the herring spawn itself. Over the past seven years, the Whale Lab has noted an increased presence of gray whales within the sound. One of their hypotheses for this increase is that a spatial shift of the herring spawn closer to the mouth of the sound has allowed northbound migrating gray whales to detect and track this resource. Another draw may be a lack of predictability and reliability in other food sources for gray whales in their more traditional feeding grounds.

This unique ecological system is the source of endless questions: How many herring eggs are the gray whales consuming? Do whales that forage on this herring spawn gain an energetic advantage at the beginning of the foraging season? Where do these whales go after leaving Sitka Sound? Do PCFG whales incorporate this foraging opportunity into their broader foraging strategies? What impact is this increased feeding aggregation having on the herring biomass in Sitka Sound? Is this new prey resource supporting gray whale population resilience to declining prey availability in the Arctic? These questions span from local to basin-wide scales, and from individual gray whale to population levels. Collaborations between the Whale Lab and the GEMM Lab allow us to address different facets of these questions more effectively, with broader impacts for local communities, gray whale populations, and the broader scientific community.

Having a Field Day!

How are we beginning to answer these questions? Dr. Wild and Dr. Chenoweth lead field seasons to capture gray whale data using photo-ID, biopsies, Go-Pro imagery, and herring roe sampling, and net-tows. I was fortunate enough to join for a week of the Whale Lab’s field season and expand their efforts by incorporating drone imagery! With drone data, we can quantify body condition and capture fine-scale behavioral patterns, particularly the tactics whales use to forage on herring roe.

The morning after I arrived, we were on the water by 9:00, heading across the sound to Fred’s Creek. I met Dr. Wild’s incredible field team including Stacey Golden – a teacher in Sitka, Kaleigh Shroeder – a fish hatchery technician, Willa Johnson – a student at the University of Alaska Fairbanks (who I would meet the next day), and Dr. Wild herself. Having flown into Sitka in the dark, I was struck with the scenery surrounding us on our trip out.

Figure 4. Dr. Wild’s research vessel facing east towards the mountains.

And it wasn’t just the mountains that were striking. As we approached the shoreline along the base of Mount Edgecumbe, I couldn’t believe my eyes when I started counting the number of blows that I was seeing. In just three hours with the Whale Lab on the first day, the best estimate of the number of whales was 28… this was whale soup! Once we reached a group of whales near the shore, we got to work. Stacey captured photo-ID pictures of each whale, Kaleigh recorded meticulous data and prepared for biopsy opportunities, I launched the drone, and Dr. Wild expertly maneuvered the boat among the whales and kelp beds. From a birds-eye view, I was able to see these groups of whales headstanding, aggregating in dense foraging groups, and even logging at the surface.Figure 4. Dr. Wild’s research vessel facing east towards the mountains.

Figure 5. (Top) whale exhibiting a headstand next to a kelp bed with attached herring eggs, (Middle) 4 whales foraging and traveling close together, and (Bottom) a whale logging amidst a kelp bed.

The aerial view also revealed the environmental context of these behaviors. Patches of herring roe were clearly visible, clinging to kelp in the water. It wasn’t until later that afternoon, when the fieldwork adrenaline settled and I started reviewing the drone footage, that I began to fully appreciate the complexity of what we had observed.

On the second day, I was able to capture one of the fascinating behaviors Dr. Wild had described: gray whales actively scraping herring eggs off kelp. While a majority of the gray whales were headstanding and foraging on the roe associated with the benthos, there were other whales pushing through kelp beds, tearing at the blades to access the eggs attached. This behavior may have broader implications, particularly for kelp-associated communities and the zooplankton species that rely on kelp as refugia later in the season – one of the many fascinating open questions about this elaborate system. That second day was also our largest survey effort of that week, with a best estimate of 154 gray whales observed along our transect!

Figure 6. (Top) Gray whale filtering sediment after foraging in the benthos and (Bottom) gray whale stripping kelp to acquire attached herring spawn. 

After returning to shore, I attended a Sitka Natural History Seminar by Matt Goff, a local naturalist who has dedicated himself to documenting and learning about Sitkan ecology. His talk, “Getting to Know our Neighbors”, highlighted a few of the over 3,000 species that he has documented on iNaturalist within the Sitka region. He also maintains a blog that documents his observations and a radio show where he hosts conversations with community members and scientists, including an October 4th, 2024 show where he interviews Dr. Wild about the gray whales.

The following day would end up being the last opportunity to fly the drone. By then, the coordination of the drone operations into the Whale Lab’s fieldwork had become seamless – calling out notes and timestamps, aligning observations, and integrating multiple data streams real time. Although the rain grounded the drone on the last day, we were still able to get out on the sound and collect photo-ID data and tissue samples with Dr. Chenoweth as well as Scott Simmons – a UAS dive instructor. As we drove back into the harbor I was trying to savor every second of being on the water in this incredible place, with these incredible people.

Figure 7. Coming into harbor with the Three Sisters mountains in the background.

Having come into an established, long-term gray whale study in Newport, Oregon (GRANITE), and then being able to experience another established, long-term gray whale study in Sitka, Alaska (Whale Lab) is a rare privilege. I am so grateful to Dr. Wild and Dr. Chenoweth for welcoming me into their homes, labs, and community. Experiencing these different ecosystems and being a part of a collaboration between two major gray whale research programs is deeply inspiring, especially at such an exciting time in gray whale research.

What the Future Holds

Looking ahead, the strength of this collaboration lies not just in the questions we are asking now, but in how adaptable this system is to the rapidly changing conditions gray whales are experiencing. As gray whales continue to navigate population-level fluctuations, understanding how localized foraging opportunities like the Sitka herring spawn fit into broader energetic and health dynamics is becoming increasingly important. Moreover, understanding the effects of the increasing number of gray whales in regions that they haven’t previously used intensively is critical for addressing questions about localized ecological impacts and community interactions. By pairing the Whale Lab’s fine-scale, system-specific work on bioenergetics and consumption with the GEMM Lab’s broader, range-wide perspective on gray whale health and ecology, we can begin to piece together how these whales are responding to shifting ecosystems. These insights are only possible through sustained monitoring and strong, reciprocal collaborations, not just between research groups, but with the communities who live alongside and are deeply connected to these whales. As generalist foragers operating across diverse and dynamic habitats, gray whales challenge us to think across scales, disciplines, and perspectives, making this continued collaborative effort more important than ever.

Figure 8. Photo of two whales surfacing in front of Mount Edgecumbe

Acknowledgements

I would like to first and foremost acknowledge the Tlingit people, who have stewarded the lands and waters around Sitka for over 10,000 years, and on whose homelands we are guests. Immense thank you to Dr. Lauren Wild and Dr. Ellen Chenoweth for hosting me and additional thanks to Dr. Wild for proofreading the first draft of this blog.

References

ADFG Herring Timeline, n.d. TIMELINE OF COMMERCIAL HERRING FISHERIES IN SOUTHEAST ALASKA.

Boots, M.T., n.d. In Sitka, spring herring spawn yields a subsistence treasure to be shared [WWW Document]. Anchorage Daily News. URL https://www.adn.com/alaska-news/rural-alaska/2026/04/18/in-sitka-spring-herring-spawn-yields-a-subsistence-treasure-to-be-shared/ (accessed 5.1.26).

Dupuis, A., Forbes, S., Meredith, B., n.d. 2026 Southeast Alaska herring sac roe fishery management plan.

Heintz, R., Moran, J., Vollenweider, J., Straley, J., Boswell, K., Rice, J., 2010. Humpback Whale Predation and the Case for Top-Down Control of Local Herring Populations in the Gulf of Alaska.

Liddle, J.B., 2015. Population dynamics of Pacific herring and humpback whales, Sitka Sound, Alaska 1981-2011 (Ph.D.). ProQuest Dissertations and Theses. University of Alaska Fairbanks, United States — Alaska.

NOAA, 2023. Pacific Herring | NOAA Fisheries [WWW Document]. NOAA. URL https://www.fisheries.noaa.gov/species/pacific-herring (accessed 5.1.26).

Starr, R., O’Connell, V., Ralston, S., 2011. Movements of lingcod (Ophiodon elongatus) in southeast Alaska: Potential for increased conservation and yield from marine reserves. Canadian Journal of Fisheries and Aquatic Sciences 61, 1083–1094. https://doi.org/10.1139/f04-054

Thornton, 2019. New study shows social, cultural, ecological benefits of herring subsistence economy are at risk [WWW Document]. University of Alaska Southeast. URL https://uas.alaska.edu/about/press-releases/2019/191122-herring-roe.html (accessed 5.1.26).

Wild, L.A., Riley, H.E., Pearson, H.C., Gabriele, C.M., Neilson, J.L., Szabo, A., Moran, J., Straley, J.M., DeLand, S., 2023. Biologically Important Areas II for cetaceans within U.S. and adjacent waters – Gulf of Alaska Region. Front. Mar. Sci. 10. https://doi.org/10.3389/fmars.2023.1134085

The behavioral specializations, adaptations, energetics, and social patterns of PCFG gray whales

Dr. Clara Bird, Postdoctoral Scholar, OSU Department of Fisheries, Wildlife, and Conservation Sciences, GEMM Lab & LABIRINTO

In one of my first GEMM lab blogs (over six years ago!) I wrote that for my thesis I was going to, “…use the drone footage to analyze gray whale behavior and how it varies across space, time, and individual.”, and I’m happy to say that I more or less accomplished that goal.  Now as I write my last blog for the GEMM lab, a whole PhD and postdoc later, I want to take this opportunity to share what we’ve learned about Pacific Coast Feeding Group (PCFG) gray whale behavior from my PhD and postdoc work.

A behavioral specialization

Given the impressive diversity of foraging tactics used by PCFG gray whales (Torres et al., 2018), a central question from the start was, “do all individuals use all behaviors, or is there variation in which whales use each behavior?”. This interest in individual specialization led to several blogs and became the question I asked in my first PhD chapter (read an introduction to specialization here and summaries of the drivers of specialization here and here). In my first chapter, I used drone data to study the relationship between individual behavior use, body length and condition, and habitat type. We found a strong relationship between foraging behavior and individual length (which is also a proxy for age). Longer, older, whales were more likely to feed using the headstanding tactic while shorter, younger, whales were more likely to feed using forward swimming tactics (Figure 1; Bird et al., 2024a). Together, these results suggest an ontogenetic shift (i.e., a shift associated with age) in foraging behavior use. Furthermore, we found that different tactics were more likely to be used in different habitats; headstanding was more likely to occur in reef habitats while the forward swimming tactics were more likely to occur in rock habitat. Overall, this chapter showed us that PCFG gray whale foraging behavior varies by length/age and habitat, indicating a lack of generalization across the group.

Figure 1. The relationship between individual total length and the probability of a behavior being used. In each box, the x-axis represents total length, and the y-axis represents the probability of that behavior (shown in the box title) being used. Figure from Bird et al. (2024a).

A behavioral adaptation

If you’ve ever watched gray whales off the coast and seen a large bubble rise to the surface, then you’ve seen a bubble blast! While we observed these bubble blasts, described as “underwater release of air that rises to surface and forms a circle/puka.” (Torres et al., 2018), fairly often in the field (Figure 2), we were never quite sure of their function, leading to my second chapter.

Figure 2. Sequential photos extracted from drone video of bubble blasts performed by PCFG gray whales during a headstand (a), side-swim stationary (b), and subsurface feeding (c). Images 1–5 in each panel show a bubble blast event from the start of the exhalation (1) to the whale continuing to feed after the bubble has diffused at the surface (5). Figure from Bird et al., (2024b).

We initially wondered if bubble blasts served a prey corralling function (like humpback whale bubble nets), but the timing and location did not fit that idea. We instead wondered if bubble blasts were being used to regulate buoyancy. The whales we study forage in water nearly as shallow (<15 m) as they are long (~12 m), meaning that they must work against their buoyancy to dive. So, like a diver releasing air from their vest to sink, we hypothesized that these whales release air from their lungs (in the form of a bubble blast) to be able to dive more efficiently. Building on this idea, we specifically hypothesized that a whale would be more likely to bubble blast if they were bigger (i.e., because they had larger lungs) and fatter (i.e., they are more buoyant due to increased blubber). To test this hypothesis, we modeled the relationship between bubble blast use, total length, and body condition and found that the probability of an individual whale bubble blasting increased with total length and body condition. Furthermore, we found that whales who bubble blasted performed longer dives than those who did not, supporting our hypothesis that bubble blasts improved dive efficiency (Bird et al., 2024b).

Behavior and energetics

The interpretation of results from my first two chapters involved many questions regarding energetics. As we’ve described in previous blogs (here and here), it is important to understand how much energy different behaviors require because energetics helps us understand foraging success. Following the results of my first chapters, we wanted to better understand if different foraging behaviors cost different amounts of energy and if bubble blasts affected the energetic cost of a dive. To ask these questions we used individual breathing patterns as a proxy for energy expenditure (read more on the method here) and explored how breathing patterns were related to individual length, body condition, and behavior (including dive duration, foraging tactic, and bubble blast use). We found that the energetic cost of a dive increased with individual length, body condition, and dive duration (Figure 3.A1-3). Interestingly, we found no relationship between foraging tactic, bubble blast use and energetic expenditure (Bird et al., 2025; Figure 3.A4). However, my second chapter showed that both foraging behavior and bubble blast use affect dive duration (Bird et al., 2024b), indicating that effects of behavior on energetics come via the dive duration variable.

Figure 3. Estimated relationships between (1) total length (TL), (2) Body Area Index (BAI), (3) preceding dive duration (s) and (4) preceding dive foraging tactic and bubble blast occurrence and (A) total inhalation duration (s). Here total inhalation duration is the sum of all inhalations following a dive; a higher value indicates higher energy expenditure during the dive. In A4 the foraging tactics have been abbreviated as follows: HS = Headstand, Side.Sw.St = Side-swim stationary, Fwd.Sw. = Forward swimming tactics, Sub.St = Subsurface stationary, Surf. = Surface tactics. Figure from Bird et al., (2025).

Social patterns

As a postdoctoral scholar I had the opportunity to pivot from PCFG foraging behavior to social behavior. We generally think of baleen whales as solitary animals with loose social structure when on their foraging grounds, including gray whales while in nearshore Oregon waters. But social structure is not well studied in gray whales and can provide important insight into how information or disease might pass through a population. To look for social patterns we first assigned whales to a group if they were seen within 10 minutes and 100 meters of each other; whales seen in the same group were determined to be “associated”. If we saw whales interact with each other (e.g., touch each other, swim in a synchronized movement) they were determined to be “interacting”. We then tallied the number of times each possible pair of whales had been seen associating and/or interacting. The higher the tally, the stronger the association. Using that dataset, we assessed if some whales were more central (i.e., had strong associations or more associations with other whales) than others and if centrality was related to sex and age. We also assessed if whales were more likely to associate with other whales of similar sex or age. Finally, we reviewed our notes from the field and drone footage and documented the kinds of social interactions we’ve observed. While we’re still wrapping up this work, I’m excited to share that we’ve found that gray whales have more social structure than previously thought, including relationships with age and sex, and documented several interesting social interactions (Figure 4). I am excited to see what more years of data collection reveal about their social patterns, especially with an emphasis on how they might be learning from each other.

Figure 4. A social interaction documented from the drone. Here one whale is pursuing the other. Collected under NMFS permit #27426.

Tying it all together

Looking ahead, I’m most curious to better understand how the PCFG successfully feed in this shallow habitat. The findings of my third chapter show that the energetic cost of foraging increases with body condition (Bird et al., 2025). I hypothesize that this increase is because it becomes physically more difficult to dive as they become more buoyant (due to the increased fat). So, while bubble blasts appear to be a behavioral adaptation to reduce buoyancy (Bird et al., 2024b), there could be a point at which a whale is too fat to continue feeding in this shallow environment. Could this be why PCFG gray whales are skinnier than the Eastern North Pacific (ENP) gray whales that feed in the deeper arctic waters (Torres et al., 2022)? Given recent evidence that the PCFG may be facing a possible population decline (Pirotta et al., 2025), these questions are more relevant than ever.

The one theme that weaves throughout all this work is the importance of individual variation. Thanks to our incredible dataset, built from years of hard work and accessible whales that keep returning to our study site, we are able to follow individuals over time and uncover the links between habitat, individual size, body condition and sex, behavior, energetics, and the whales themselves. 

While I am sad to be leaving the GEMM lab, I am certainly proud of all that we have learned so far and excited to see what’s next (as an avid reader of the blog of course).

Did you enjoy this blog? Want to learn more about marine life, research, and conservation? Subscribe to our blog and get a weekly alert when we make a new post! Just add your name into the subscribe box below!

References

Bird CN, Pirotta E, New L, Bierlich KC, Donnelly M, Hildebrand L, Fernandez Ajó A, Torres LG. 2024a. Growing into it: evidence of an ontogenetic shift in grey whale use of foraging tactics. Animal Behaviour 214:121–135. DOI: 10.1016/j.anbehav.2024.06.004.

Bird CN, Pirotta E, New L, Bierlich KC, Hildebrand L, Fernandez Ajó A, Torres LG. 2024b. Bubble blasts! An adaptation for buoyancy regulation in shallow foraging gray whales. Ecology and Evolution 14:e70093. DOI: 10.1002/ece3.70093.

Bird CN, Pirotta E, New L, Cornelius JM, Sumich JL, Colson KM, Bierlich KC, Hildebrand L, Ajó AAF, Doron A, Torres LG. 2025. Size and body condition drive the energetic cost of a baleen whale foraging in shallow habitat. PeerJ13:e20247. DOI: 10.7717/peerj.20247.

Pirotta E, New L, Fernandez Ajó A, Bierlich KC, Bird CN, Buck CL, Hildebrand L, Hunt KE, Calambokidis J, Torres LG. 2025. Body size, nutritional state and endocrine state are associated with calving probability in a long-lived marine species. Journal of Animal Ecology 94:1–13. DOI: 10.1111/1365-2656.70068.

Torres LG, Bird CN, Rodríguez-González F, Christiansen F, Bejder L, Lemos L, Urban R J, Swartz S, Willoughby A, Hewitt J, Bierlich KC. 2022. Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change. Frontiers in Marine Science 9:1–13. DOI: https://doi.org/10.3389/fmars.2022.867258.

Torres LG, Nieukirk SL, Lemos L, Chandler TE. 2018. Drone up! Quantifying whale behavior from a new perspective improves observational capacity. Frontiers in Marine Science 5:1–14. DOI: 10.3389/fmars.2018.00319.

How Humans and Cetaceans Shape Each Other

Marc Rams i Rios, PhD Student, Oregon State University Department of Fisheries, Wildlife, and Conservation Sciences, Geospatial Ecology of Marine Megafauna Lab

When I moved to Oregon to begin my PhD, I pictured long days on the water watching gray whales feed and travel along the coast. That does happen, and it is as incredible as I imagined. But I have learned that studying cetaceans is about much more than observing whales. It is also about people: how cultures – past and present – perceive these animals and share space with them.

In addition to marine mammals, I have always loved history and geography. Now, as I start my work with the GRANITE Project in the GEMM Lab, I find myself thinking about how these relationships between humans and whales unfold across time and space. In this post, I want to share a few examples of how whales have shaped human traditions for hundreds, even thousands of years, across societies that have never crossed. Then I will discuss how our research fits into this larger picture of human–cetacean connections.

Our journey begins in India, where the Ganges River dolphin inhabits a river that millions of people consider sacred. Its presence has long been linked to the health of the river, giving the species spiritual and cultural significance. Over the past century, the river’s ecological integrity has declined due to pollution, altered flow, and habitat disturbances, and this has caused the dolphin population to diminish1, 2. Conservation efforts that improve water quality, restore natural flow, and reduce disturbances not only help the dolphin recover but also protect the river and the human communities that rely on it1, 2. In this way, cultural reverence for the dolphin drives conservation measures that benefit both people and ecosystems1, 2.

© WWF Mohd Shahnawaz Khan

From there we move to Aotearoa, New Zealand, where Māori tradition speaks of tohorā, or whales, as guardians and ancestors3. They appear in ancestral stories as guides and protectors, and whale strandings have historically brought communities together in collective response. The Māori principles of kaitiakitanga, or guardianship, continue to shape marine conservation decisions today, guiding policies that integrate ecological and cultural values4. Here, whales are not seen as resources. They are part of a living genealogy that binds people to the sea and the life it sustains. In fact, team members of the SAPPHIRE project in the GEMM lab frequently engage with multiple iwi (Māori tribes) across Aotearoa through hui (meetings) where knowledge, stories, and culture are shared about blue whales and their ecosystem.

Traveling nearly to the antipodes, we arrive on the Atlantic coast of Brazil, in the town of Laguna, where an extraordinary partnership has endured for centuries. Artisanal fishers work alongside bottlenose dolphins, who drive schools of fish toward the shore and signal the right moment to cast the nets5, 6, 7. This cooperation benefits both species, and the knowledge behind it is passed down through generations of humans and dolphins through observation and shared practice5, 6, 7. It is a powerful example of how species can learn from one another, creating connections that challenge the idea of humans and wildlife as competitors and showing the potential for collaboration across species5, 6, 7. The LABIRINTO Lab in MMI has studied this interspecific relationship for decades, helping us learn about the patterns and endurance of these cultures.

PELD-SELA: Long-term ecological project on the Laguna Estuarine System and Adjacent Areas Projects. (n.d.). https://thelabirinto.com/projects1/

At the top of the Americas, in the Arctic, Inuit communities have hunted bowhead whales for thousands of years. These hunts are not only a source of food but also form the foundation of cultural identity and social life8. Knowledge of the ice, weather, and whale behavior is passed down through generations, and the hunt itself is embedded in ceremonies and practices that sustain the community8. Today, these traditions continue under strict quotas set through international agreements, carefully balancing cultural continuity with conservation9. The MMBEL lab in MMI studies the communication and ecology of bowhead whales to support the survival of this iconic species and the culture of Inuit people.

Emory Kristoff, National Geographic

Finally, our journey brings us to Oregon, where gray whales feed along a coastline rich with reefs, kelp beds, and sandy bottoms. These waters support a variety of human activities, from commercial fishing to recreation, creating risks such as entanglement, vessel strikes, and disturbance10, 11. Even well-intentioned actions like whale watching can cause harm if not carefully managed12, 13. Around the world, many communities have shifted from whaling to whale watching, transforming former hunting grounds into tourism destinations. While this is a positive change, it still requires monitoring. Noise can stress whales, boats can disrupt their behavior, and too much interaction can alter natural feeding and social patterns12, 13. In Oregon, research on gray whale habitat use and feeding home ranges helps inform management and conservation14.

Tradewind Charters Whale Watching and Fishing

This is where project GRANITE, Gray whale Response to Ambient Noise Informed by Technology and Ecology, comes in15. The project studies how whales respond to human activities by using drones to monitor health and behavior, photo-ID to track individuals, prey mapping to understand feeding choices, and acoustic recorders to capture the soundscape15, 16, 17. Equally important is collaborating directly with fishers and resource managers to reduce risks and develop solutions that benefit both whales and people. Healthy whale populations support communities too, through ecotourism, cultural continuity, education, and the ecological services whales provide. Conservation is reciprocal: caring for whales strengthens the ocean systems that sustain us all.

The tools and techniques developed by GRANITE, including drones, acoustic monitoring, and prey mapping, are not limited to Oregon. They can be applied globally, contributing to the protection of cetaceans in diverse habitats15. In this way, Oregon becomes more than the final stop on our tour. It is a place where centuries of human–whale relationships, lessons from around the world, and modern science converge. These examples across the world remind us that conservation is about more than preventing harm. It is about fostering a future where humans and whales thrive together, as they have shared the ocean for millennia.

Did you enjoy this blog? Want to learn more about marine life, research, and conservation? Subscribe to our blog and get a monthly message when we post a new blog. Just add your name and email into the subscribe box below.

References

1 Sinha, R. K., & Kannan, K. (2014). Ganges river dolphin: An overview of biology, ecology, and conservation status in India. AMBIO, 43(8), 1029–1046. https://doi.org/10.1007/s13280-014-0534-7

2 Braulik, G., Atkore, V., Khan, M. S., & Malla, S. (2021). Review of scientific knowledge of the Ganges river dolphin. WWF. https://riverdolphins.org/wp-content/uploads/2021/07/Ganges-River-dolphin-Scientific-Knowledge-Review-July2021.pdf

3 Taonga, N. Z. M. for C. and H. T. M. (n.d.). Whales in Māori tradition. Teara.govt.nz. https://teara.govt.nz/en/te-whanau-puha-whales/page-1

4 McAllister, T., Hikuroa, D., & Macinnis‑Ng, C. (2023). Connecting science to Indigenous knowledge: Kaitiakitanga, conservation, and resource management. New Zealand Journal of Ecology, 47(1), 3521. https://doi.org/10.20417/nzjecol.47.3521

5 Simões‑Lopes, P. C., Fabián, M. E., & Menegheti, J. O. (1998). Dolphin interactions with the mullet artisanal fishing on southern Brazil: A qualitative and quantitative approach. Revista Brasileira de Zoologia, 15(3), 709–726. https://doi.org/10.1590/S0101-81751998000300008

6 Daura Jorge, F. G., Cantor, M., Ingram, S. N., Lusseau, D., & Simões Lopes, P. C. (2012). The structure of a bottlenose dolphin society is coupled to a unique foraging cooperation with artisanal fishermen. Biology Letters, 8(5), 702–705. https://doi.org/10.1098/rsbl.2012.0174

7 Cantor, M., Farine, D. R., & Daura‑Jorge, F. G. (2023). Foraging synchrony drives resilience in human–dolphin mutualism. Proceedings of the National Academy of Sciences, 120(6), e2207739120. https://doi.org/10.1073/pnas.2207739120

8 Jensen, A. M. (2012). The material culture of Iñupiat whaling: An ethnographic and ethnohistorical perspective. Arctic Anthropology, 49(2), 143–161. https://doi.org/10.1353/arc.2012.0020

9 Description of the USA Aboriginal Subsistence Hunt: Alaska. (n.d.). Iwc.int. https://iwc.int/management-and-conservation/whaling/aboriginal/usa/alaska

10 Derville, S., Buell, T. V., Corbett, K. C., Hayslip, C., & Torres, L. G. (2023). Exposure of whales to entanglement risk in Dungeness crab fishing gear in Oregon, USA. Biological Conservation, 281, 109989. https://doi.org/10.1016/j.biocon.2023.109989

11 Silber, G. K., Weller, D. W., Reeves, R. R., Adams, J. D., & Moore, T. J. (2021). Co‑occurrence of gray whales and vessel traffic in the North Pacific Ocean. Endangered Species Research, 44, 177–201. https://doi.org/10.3354/esr01093

12 Sullivan, F. A., & Torres, L. G. (2018). Assessment of vessel disturbance to gray whales to inform sustainable ecotourism. Journal of Wildlife Management, 82(5), 896–905. https://doi.org/10.1002/jwmg.21462

13 Sprogis, K. R., Videsen, S., & Madsen, P. T. (2020). Vessel noise levels drive behavioural responses of humpback whales with implications for whale‑watching. eLife, 9, e56760. https://doi.org/10.7554/eLife.56760

14 Lagerquist, B. A., Palacios, D. M., Winsor, M. H., Irvine, L. M., Follett, T. M., & Mate, B. R. (2019). Feeding home ranges of Pacific Coast Feeding Group gray whales. Journal of Wildlife Management, 83(4), 925–937. https://doi.org/10.1002/jwmg.21642

15 GRANITE: Gray whale Response to Ambient Noise Informed by Technology and Ecology | Marine Mammal Institute | Oregon State University. (n.d.). Mmi.oregonstate.edu. https://mmi.oregonstate.edu/gemm-lab/granite-gray-whale-response-ambient-noise-informed-technology-ecology

16 Pirotta, E., Bierlich, K. C., New, L., Bird, C. N., Fernandez Ajó, A., Hildebrand, L., Buck, C. L., Hunt, K. E., Calambokidis, J., & Torres, L. G. (2025). Body size, nutritional state and endocrine state are associated with calving probability in a long‑lived marine species. Journal of Animal Ecology. Advance online publication. https://doi.org/10.1111/1365-2656.70068

17 Bierlich, K. C., Kane, A., Hildebrand, L., Bird, C. N., Fernandez Ajó, A., Stewart, J. D., Hewitt, J., Hildebrand, I., Sumich, J., & Torres, L. G. (2023). Downsized: Gray whales using an alternative foraging ground have smaller morphology. Biology Letters, 19(7), 20230043. https://doi.org/10.1098/rsbl.2023.0043

‌

New GEMM Lab study indicates troubled times for PCFG gray whales

Dr. Enrico Pirotta (CREEM, University of St Andrews) and Dr. Leigh Torres (GEMM Lab, MMI, OSU)

The health of animals affects their ability to survive and reproduce, which, in turn, drives the dynamics of populations, including whether their abundance trends up or down. Thus, understanding the links between health and reproduction can help us evaluate the impact of human activities and climate change on wildlife, and effectively guide our management and conservation efforts. In long-lived species, such as whales, once a decline in population abundance is detected, it can be too late to reverse the trend, so early warning signals are needed to indicate how these populations are faring.

We worked on this complex issue in a study that was recently published in the Journal of Animal Ecology. In this paper, we developed a new statistical approach to link three key components of the health of a Pacific Coast Feeding Group (PCFG) gray whale (namely, its body size, body condition, and stress levels) to a female’s ability to give birth to a calf. We were able to inform these metrics of whale health using an eight-year dataset derived from the GRANITE project of aerial images from drones for measurements of body size and condition, and fecal samples for glucocorticoid hormone analysis as an indicator of stress. We combined these data with observations of females with or without calves throughout the PCFG range over our study period.

We found that for a female to successfully have a calf, she needs to be both large and fat, as these factors indicate if the female has enough energy stored to support reproduction that year (Fig. 1). Remarkably, we also found indication that females with particularly high stress hormone levels may not get pregnant in the first place, which is the first demonstration of a link between stress physiology and vital rates in a baleen whale, to our knowledge.

Figure 1. Taken from Pirotta et al. (2025), Fig. 5. Combined relationship of PCFG gray whale length and nutritional state (combination of body size and condition) in the previous year with calving probability, colored by whether the model estimated an individual to have calved or not at a given reproductive opportunity.

Our study’s findings are concerning given our previous research indicating that gray whales in this PCFG sub-group have been growing to shorter lengths over the last couple of decades (Pirotta et al. 2023), are thinner than animals in the broader Eastern North Pacific gray whale population (Torres et al, 2022), and show an increase in stress-related hormones when exposed to human activities (Lemos et al, 2022; Pirotta et al. 2023). Furthermore, in our recent study we also documented that there are fewer young individuals than expected for a growing or stable population (Fig. 2), which can be an indicator of a population in decline since there may not be many individuals entering the reproductive adult age groups. Altogether, our results act as early warning signals that the PCFG may be facing a possible population decline currently or in the near future.

Figure 2. Taken from Pirotta et al. (2025), Fig. 1. Age structure diagram for 139 PCFG gray whales in our dataset. Each bar represents the number of individuals of a given age in 2023, with the color indicating the proportion of individuals of that age for which age is known (vs. estimated from a minimum estimate following Pirotta, Bierlich, et al., 2024). The red line reports a smooth kernel density estimate of the distribution.

These findings are sobering news for Oregon residents and tourists who enjoy watching these whales along our coast every summer and fall. We have gotten to know many of these whales so well – like Scarlett, Equal, Clouds, Lunita, and Pacman, who you can meet on our IndividuWhale website – that we wonder how they will adapt and survive as their once reliable habitat and prey-base changes. We hope our work sparks collective and multifaceted efforts to reduce impacts on these unique PCFG whales, and that we can continue the GRANITE project for many more years to come to monitor these whales and learn from their response to change.

This work exemplifies the incredible value of long-term studies, interdisciplinary methods, and effective collaboration. Through many years of research on this gray whale group, we have collected detailed data on diverse aspects of their behavior, ecology and life history that are critical to understanding their response to disturbance and environmental change, which are both escalating in the study region. We are incredibly grateful to the following members of the PCFG Consortium for contributing sightings and calf observation data that supported this study: Jeff Jacobsen, Carrie Newell, NOAA Fisheries (Peter Mahoney and Jeff Harris), Cascadia Research Collective (Alie Perez), Department of Fisheries and Oceans, Canada (Thomas Doniol-Valcroze and Erin Foster), Mark Sawyer and Ashley Hoyland, Wendy Szaniszlo, Brian Gisborne, Era Horton.

Did you enjoy this blog? Want to learn more about marine life, research, and conservation? Subscribe to our blog and get a weekly alert when we make a new post! Just add your name into the subscribe box below!

References:

Lemos, Leila S., Joseph H. Haxel, Amy Olsen, Jonathan D. Burnett, Angela Smith, Todd E. Chandler, Sharon L. Nieukirk, Shawn E. Larson, Kathleen E. Hunt, and Leigh G. Torres. “Effects of Vessel Traffic and Ocean Noise on Gray Whale Stress Hormones.” Scientific Reports 12, no. 1 (2022): 18580. https://dx.doi.org/10.1038/s41598-022-14510-5.

Pirotta, Enrico, K. C. Bierlich, Leslie New, Lisa Hildebrand, Clara N. Bird, Alejandro Fernandez Ajó, and Leigh G. Torres. “Modeling Individual Growth Reveals Decreasing Gray Whale Body Length and Correlations with Ocean Climate Indices at Multiple Scales.” Global Change Biology 30, no. 6 (2024): e17366. https://doi.org/https://doi.org/10.1111/gcb.17366. https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.17366.

Pirotta, Enrico, Alejandro Fernandez Ajó, K. C. Bierlich, Clara N Bird, C Loren Buck, Samara M Haver, Joseph H Haxel, Lisa Hildebrand, Kathleen E Hunt, Leila S Lemos, Leslie New, and Leigh G Torres. “Assessing Variation in Faecal Glucocorticoid Concentrations in Gray Whales Exposed to Anthropogenic Stressors.” Conservation Physiology 11, no. 1 (2023). https://dx.doi.org/10.1093/conphys/coad082.

Torres, Leigh G., Clara N. Bird, Fabian Rodríguez-González, Fredrik Christiansen, Lars Bejder, Leila Lemos, Jorge Urban R, et al. “Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change.” Frontiers in Marine Science 9 (2022). https://doi.org/10.3389/fmars.2022.867258. https://www.frontiersin.org/article/10.3389/fmars.2022.867258