In the frigid waters of British Columbia’s Central Coast, scientists from the Hakai Institute have discovered vital information about the endangered sunflower sea stars, known scientifically as Pycnopodia helianthoides. New research suggests that these creatures are not perishing entirely from the ravages of sea star wasting disease (SSWD), contrary to what many had believed. Instead, a unique set of ecological factors surrounding the fjords seems to act as a sanctuary for these remarkable marine animals.
The sunflower sea star is a striking entity, capable of growing up to 20 arms and spanning a meter across, making it an iconic species in the Pacific Northwest. Historically, this keystone predator thrived in the intertidal zones, serving a crucial role in maintaining ecological balance, particularly through the control of populations of bottom-dwelling species like sea urchins. These interactions are fundamental for the preservation and health of kelp forests, which are vital ecosystems that provide habitat for countless marine species.
However, since the onset of SSWD in 2013—a marine disease that decimated more than 90 percent of sunflower sea star populations ranging from Alaska down to Mexico—the species has faced dire challenges. The outbreaks of this disease have tended to coincide with episodes of marine heatwaves, events that have become alarmingly frequent due to climate change. One poignant hypothesis has emerged from this catastrophic decline: that consistently cold waters might serve as refuge zones where Pycnopodia could survive.
In light of this hypothesis, researchers collaborated with the Central Coast Indigenous Resource Alliance (CCIRA) and Fisheries and Oceans Canada (DFO) to investigate the fjords of the Central Coast. It was local Indigenous members who first observed the presence of larger sunflower sea stars in these fjords, which turned out to be crucial remnants of a once-thriving population that had seemingly escaped the devastation of SSWD. Alyssa Gehman, a research scientist from the Hakai Institute and lead on this study, recalls her stunning dive experience in Burke Channel, remarking that it revealed a vibrant subtidal ecosystem reminiscent of what existed prior to the health crisis that afflicted sea stars across the region.
Contrary to expectations, the study indicated that sea stars in fjord environments were considerably larger and more abundant than their counterparts found on offshore islands. Gehman highlighted that the fjords have distinct oceanographic phenomena at play, which include the seasonal dynamics brought about by Arctic storms in winter that churn cold, oxygen-rich waters into the ecosystem. During the summer months, melting snow and glacial runoff create a unique stratification, resulting in a surface layer of low-salinity water that acts like a barrier holding some species down.
Interestingly, this research revealed that Pycnopodia responds to these environmental variations differently in fjord ecosystems than it does elsewhere. In the fjords, these sea stars were observed to venture deeper into the water, beyond the depth of snowmelt influence, allowing them to reach cooler waters that seem to contribute to their resilience against SSWD. This interaction indicates that these fjords function not merely as geographic features, but as critical microhabitats that can provide refuge from daunting environmental changes.
Gehman emphasized the complexities of how these dynamic fjord environments may impact sea star health and resilience. She articulated how the interplay of temperature and salinity in these waters creates a novel protective mechanism for the sunflower sea stars, demonstrating how marine ecosystems can evolve to confront climate-induced challenges. However, it is essential to note that these fjords are not immune to the ramifications of climate change. For example, in 2024, the region experienced a significant reduction in snow, a change that could have dire consequences for the local sea star populations.
The implications of this study extend beyond scientific curiosity; they resonate deeply with Indigenous knowledge and conservation efforts. Mike Reid, fisheries manager for the Heiltsuk First Nation, highlighted the importance of understanding the historical environmental context in painting a picture of sustainability. He discussed how the Indigenous peoples of the region have long managed their resources, ensuring that essential species like kelp flourished in these critical habitats. This aligns with what the study reveals—that certain fjords can support not only sea stars but also contribute to the health of kelp forests, which are indispensable for marine biodiversity and ecological resilience against climate shifts.
The findings serve as a troubling reminder that no species is immune to the pervasive effects of anthropogenic climate change. As researchers and Indigenous communities continue to collaborate and combine their knowledge systems, they pave the way for more informed conservation strategies that recognize the importance of microclimates, dynamic ecosystems, and the intricate web of environmental factors that support marine life. There is a collective understanding that addressing the threats posed by climate change requires a holistic approach, one that honors both traditional knowledge and scientific inquiry.
The research conducted over more than a decade has provided a robust dataset that merges detailed oceanographic data with dive surveys, offering a comprehensive understanding of the marine dynamics at play in British Columbia’s fjords. This work illustrates the potential of these unique environments to serve as living laboratories for studying climate resilience and species conservation. As we move forward, the lessons learned from the Pycnopodia and its survival in these fjords may become critical in understanding how to protect and preserve other vulnerable marine species facing the impending crises of climate change.
Field observations coupled with data-driven research create a narrative that goes beyond mere documentation; it holds implications for future marine science, policy-making, and community engagement in conservation. The collective enthusiasm and urgency expressed by researchers and Indigenous partners bolster the call for further study, advocacy, and action—a concerted effort to safeguard these atmospheric spaces that might just hold the key to the future of endangerment and refuge in marine ecosystems.
Through these revelations, the Hakai Institute continues its mission to drive knowledge across coastal boundaries and ensure that the ecosystems along British Columbia’s coastal range retain the vibrancy that has characterized them through time. The findings reported underscore the interconnectedness of organisms, human management practices, and climatic events, forming a mosaic that reflects both the challenges and opportunities that await as we strive towards greater ecological understanding and stewardship.
In essence, the research on the sunflower sea stars in the fjords acts as a reminder that even amidst environmental upheaval, hope can manifest in unexpected places. As the glaciers continue to melt and ecosystems face unprecedented changes, the lessons learned from these resilient sea stars could very well inform broader ecological strategies aimed at navigating the intricacies of climate change.
Subject of Research: Animals
Article Title: Fjord oceanographic dynamics provide refuge for critically endangered Pycnopodia helianthoides
News Publication Date: April 2, 2025
Web References: Hakai Institute, Tula Foundation, CCIRA
References: Gehman A-LM et al. “Fjord oceanographic dynamics provide refuge for critically endangered Pycnopodia helianthoides.” Proceedings of the Royal Society B: Biological Sciences April 2025. DOI: 10.1098/rspb.2024.2770.
Image Credits: Photo courtesy of Bennett Whitnell/Hakai Institute, Grant Callegari/Hakai Institute.
Keywords: Sunflower sea stars, marine ecosystem, climate change, fjords, biodiversity, conservation, Indigenous knowledge, oceanography, sea star wasting disease.
