“If you remove it, they will come” — that’s what officials have been saying for years in their attempts to remove fish barriers from local creeks once frequented by the now-endangered Southern California Steelhead Trout. And they proved to be correct when, just two weeks after completion of a project to remove two major fish barriers on Arroyo Sequit Creek in Leo Carrillo State Park, a large steelhead was spotted by officials upstream.
“We had been planning to remove these barriers for over 15 years, and it was so exciting that within two weeks there was rain, and we immediately had a fish,” Suzanne Goode, senior biologist for California State Parks, said. “They’re ready to respond under the right conditions. It’s a really special mission to improve their passage.”
The project involved removing two low-water “Arizona Crossings” in Arroyo Sequit and replacing them with free span bridges.
Rosi Dagit, senior conservation biologist for the Resource Conservation District of the Santa Monica Mountains, was on a regular monthly snorkel survey with her “Stream Team” near the end of January when she spotted the trout.
“These fish have such an unusual life history of hatching in a creek, going out to the ocean, and then coming back to a creek — not necessarily the same creek,” Dagit said. “That flexibility is key to their survival, because you never know when rain will open up a particular creek to the ocean. This is the first time a steelhead has been spotted there since 2011. Last year, because of the drought, the creek dried up almost completely.”
Dagit said the southern steelhead trout is more endangered than ever, not only because of fish barriers like dams and bridges on creeks, but because of the long drought. “For six years, there was no connection to the ocean,” she explained. She said the Arroyo Sequit trout was one of only four adults found so far this year between San Luis Obispo and the Mexican border, the only area where they live.
Although nearly 900 young fish were tagged almost 10 years ago in 2008, none of the ones that went out to sea have returned.
“They are so close to extinction,” she said. “That’s a despicably low number. And sadly, one of the four died in my hands just last Wednesday.” The crew was doing a snorkel survey in Malibu Creek and saw the 23-inch-long fish lying on its back on the bottom, still alive. They tried holding it up to give it as much oxygen as possible, but said the fish was “all banged up and her scales were abraded.” The fish was in bad shape and did not survive.
A necropsy showed she had eggs, but they were still immature, and her stomach was “totally empty.” Various scale and tissue samples have been sent off to the National Marine Fisheries Service for analysis.
“I’ve spent 17 years working to save this species,” Dagit said. “What’s interesting and unusual about the southern steelhead trout is their tolerance to warmer waters than most trout can tolerate. A northern steelhead trout would die down here. The southern steelhead will even continue to grow in warmer waters.”
The Southern California fish were identified as unique and different from the Northern California trout in 1997 by genetic analysis,” Dagit explained. “The southern steelhead are actually an older species than the northern. They may be our hope for the future, because as ocean temperatures rise because of global warming, they’ll continue to survive.”