Recent research led by California Sea Grant Extension Specialist Mariska Obedzinski reveals that even small amounts of running water in coastal California streams can mean survival instead of death for juvenile coho salmon.

Three fish biologists from the group California Sea Grant climb into big black balloon-like dry suits, hop over fences and scurry down steep river banks, whacking away brush to get to the river bed.

They spit in their goggles to stop them from fogging up, check to make sure their field computers and flashlights are working, and prepare themselves for a face full of cold water.

Whether or not you consider yourself a health nut, you're probably aware of the hot debate revolving around the health benefits of farmed vs. wild salmon. "Farmed Atlantic salmon are hatched, raised, and harvested under controlled conditions and available fresh year round," said Pamela Tom and Paul Olin of the University of California Sea Grant Extension Program.

In California's small coastal streams, where hundreds of thousands of Coho salmon once returned each year to spawn, most wild populations now barely cling to survival. Habitat loss and intensive water use have pushed them to the brink; now climate change and increasing competition for water resources could send them over the edge.

However, recent research offers some encouraging findings – that juveniles of Coho salmon, an endangered species in California, can survive in creeks where just a trickle of water remains flowing. Since Coho spend their entire first year in fresh water before heading for the sea, it’s critical that their creeks don’t dry out in the summer.

Scientist Mariska Obedzinski and three collaborators – Sarah Nossaman Pierce, a California Sea Grant Extension specialist; Gregg Horton, a principal environmental specialist at the Sonoma County Water Agency; and Matthew Deitch, an assistant professor of watershed management at the University of Florida – found that less than 1 gallon per second of flow in small streams is all it takes in some creeks to keep pools interconnected.

A portrait of a California condor, one of the world's largest flying birds, hangs opposite the desk of Nathan Dodder. The image is a constant reminder of the threatened bird that the San Diego State University analytical chemist is working to help save.

Along with SDSU environmental scientist Eunha Hoh and colleagues at the San Diego Zoo, Dodder recently received funding from California Sea Grant to study environmental toxins found along the coast that could impact the condor's reproductive success.
 

Even small amounts of running water—less than a gallon per second—could mean the difference between life or death for juvenile coho salmon in coastal California streams, according to a new study published in the journal Transactions of the American Fisheries Society.

The study, led by California Sea Grant Extension Specialist Mariska Obedzinski, shows that during dry periods, that amount of water was enough to keep pools interconnected, allowing young salmon to survive through the hot, dry summer months.