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Ocean Expedition Seeks Elusive Elder Rockfish
31 Jul
Summary
- Three female rockfish species have largely vanished from the West Coast.
- Scientists are searching for these older fish off the coast of California.
- Disappearance may be linked to natural causes or unknown factors.
Off the coasts of California, Oregon, Washington, Canada, and Alaska, three species of female rockfish have significantly diminished over the past four decades. To understand this concerning trend, scientists embarked on an expedition in August 2026, venturing westward into the North Pacific Gyre and to the Cobb Seamount. This underwater volcano's shelf provides a unique marine ecosystem, while the gyre is one of Earth's major rotating ocean currents.
Historical records from the 1960s suggest the presence of larger, older female black, canary, and yellowtail rockfish, which are now rarely encountered. While these species can live for many decades, catches have increasingly shown very few females over 30 years old. This decline has prompted research into potential causes, including overlooked habitats, selective fishing impacts, or migration to offshore areas like the North Pacific Gyre.
The expedition's findings could be vital for fisheries management and understanding the long-term health of rockfish populations. Researchers are investigating if these elder females are genetically related to coastal populations and what their diet might be. The complexities of accessing international waters for research, regulated by the North Pacific Fisheries Commission, added significant policy challenges to the expedition's planning.
