Rising water temperatures, acidification, and deoxygenation are disrupting marine ecosystems worldwide. These changes threaten culturally and economically significant species, ultimately endangering the livelihoods that depend on them. To manage marine species struggling with climate change, it is essential to identify the most vulnerable ecosystems and species.
A study conducted by the University of California, Santa Cruz, aims to help Californian fisheries adapt by developing climate-ready management strategies. The research team collaborated with the California Department of Fish and Wildlife (CDFW), fisheries scientists from the National Oceanic and Atmospheric Administration (NOAA), and experts from the Nature Conservancy and the California Ocean Protection Council to assess the climate vulnerability of 34 key aquatic species.
"The results are striking," said Timothy Frawley, an assistant project scientist at UC Santa Cruz’s Institute of Marine Sciences and lead author of the study, in a press release. "Some of California's most economically and culturally important fisheries are among the most vulnerable to projected environmental changes."
Climate Change Impact on Marine Species
Key factors influencing species vulnerability include reproductive rate, habitat range, and susceptibility to ocean acidification. Oceanographic changes — such as rising sea surface temperatures, altered salinity, declining subsurface oxygen levels, and sea-level rise — also play a critical role.
One of the first noticeable shifts is in species distribution. As marine organisms adapt to changing environments, some — such as Pacific herring and market squid — are moving northward. This shift could push them beyond the reach of local fisheries, creating economic challenges. Conversely, species like the Pacific bonito may find Californian waters more suitable, presenting new fishing opportunities.
Read More: Poop of the Ocean's Tiniest Organisms Could Combat Climate Change
Classifying Vulnerability
The researchers used Climate Vulnerability Assessments (CVA) to gauge species’ susceptibility to environmental change. The system ranks species on a scale from blue (least vulnerable) to red (most vulnerable).
Findings suggest that between 2030 and 2060, 12 percent of the 34 species studied will fall into the high-risk orange and red categories. This percentage is projected to rise to 53 percent between 2070 and 2100. The study notes that these results align with ongoing climate-driven changes already observed in marine ecosystems.
Species with limited mobility, such as red abalone — a sea snail—are particularly vulnerable because they cannot easily relocate in response to environmental changes and thus classified as highly at risk. Other species, including Pacific herring, Dungeness crab, Pismo clam, market squid, California spiny lobster, and pink shrimp, may also reach critical vulnerability levels if climate impacts intensify.
These species play a vital role in California’s economy. Dungeness crab alone contributes approximately $45 million annually to local and regional economies. Fisheries identified as highly vulnerable have already experienced significant declines, further underscoring the need for proactive management strategies.
How Fisheries Face the Future
Frawley emphasizes that the fishing industry depends on a vast network of workers to function efficiently. Beyond boat crews, the industry relies on dock workers, processing plant staff, and buyers. Scientists play a crucial role in establishing sustainable harvest levels and ensuring long-term viability.
"My experience as a fisherman has inspired me to focus my work as a marine scientist on supporting coastal communities by providing them with the information needed to better navigate risk and uncertainty," Frawley stated in the release.
Local assessments are crucial, as species that migrate to different areas may avoid extinction but still create challenges for regional fisheries. When fish populations shift beyond fishermen’s reach, their livelihoods suffer. Understanding these trends in advance allows fisheries to adapt while prioritizing conservation efforts.
The study suggests that more flexible management approaches will be necessary to address climate-driven fluctuations in species distribution and population dynamics. Adjusting fishing regulations to reflect these changes will be key to sustaining both marine biodiversity and the fishing industry in the years to come.
Read More: Carbon Is Robbing Crabs of Their Senses
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
PLOS Climate: A collaborative climate vulnerability assessment of California marine fishery species
UC Santa Cruz: Economically, culturally important marine species vulnerable to changing climate, new study shows
NOAA Fisheries: Climate Vulnerability Assessments
Having worked as a biomedical research assistant in labs across three countries, Jenny excels at translating complex scientific concepts – ranging from medical breakthroughs and pharmacological discoveries to the latest in nutrition – into engaging, accessible content. Her interests extend to topics such as human evolution, psychology, and quirky animal stories. When she’s not immersed in a popular science book, you’ll find her catching waves or cruising around Vancouver Island on her longboard.
