By Kathleen Wong

Local green sturgeon are struggling. The population that spawns in the Sacramento –San Joaquin River Delta was declared federally threatened in 2006. Researchers at UC Davis, which hosts the world’s only green sturgeon rearing program, are now trying to figure out why the fish is in trouble. “If we knew how large they are when they’re moving through each portion of the system, we’d know a lot more about the threats they face at each life stage, and where we need to put our energy,” says postdoctoral fellow Anna Steel. While the researches have tentatively ruled out some threats such as predation by invasive species or destruction via the Tracy pumps, they haven’t yet pinpointed the cause of the sturgeon’s demise. A combination of factors that have been changing or intensifying over time may be to blame.

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Sleuthing Sturgeon Snags

By Kathleen Wong

Local green sturgeon are struggling. The population that spawns in the Sacramento –San Joaquin River Delta was declared federally threatened in 2006. Researchers at UC Davis, which hosts the world’s only green sturgeon rearing program, are now trying to figure out why the fish is in trouble. “If we knew how large they are when they’re moving through each portion of the system, we’d know a lot more about the threats they face at each life stage, and where we need to put our energy,” says postdoctoral fellow Anna Steel. While the researches have tentatively ruled out some threats such as predation by invasive species or destruction via the Tracy pumps, they haven’t yet pinpointed the cause of the sturgeon’s demise. A combination of factors that have been changing or intensifying over time may be to blame.

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About the author

Bay Area native Kathleen M. Wong is a science writer specializing in the natural history and environment of California and the West. With Ariel Rubissow Okamoto, she coauthored Natural History of San Francisco Bay (UC Press, 2011), for which she shared the 2013 Harold Gilliam Award for Excellence in Environmental Reporting. She reports on native species, climate change, and environmental conditions for Estuary, and is the science writer of the University of California Natural Reserve System.

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