Mudslide buries remnant group of native SoCal trout
SANTA ANA, Calif. ” A mudslide in fire damaged Orange County wiped out one of the last remaining populations of native rainbow trout in Southern California.
“What we feared, happened,” said Adam Backlin, an ecologist with the U.S. Geological Survey. “The hillsides just slumped into the canyon, and buried the entire creek.”
Backlin said he became concerned about the Harding Canyon trout after the Santiago fire, which burned more than 28,000 acres during the October wildfires, creating mudslide conditions.
The fish lived in rocky pools along a stretch of creek.
The loss is just one example of how many of Southern California’s dwindling species teeter on the edge of disappearing completely. The once thriving populations of fish and amphibians have shrunken into small pockets easily threatened by storms and mudslides.
Backlin had tried to arrange with the Department of Fish and Game to temporarily remove the fish, fearing that one good rain could fill the trouts’ refuges with mud. When it did rain, the trout disappeared under as much as six feet of mud.
This isn’t the first time a post-wildfire mudslide appeared to wipe out a population of animals. In 2003, the last mountain yellow-legged frogs in the San Bernardino Mountains appeared to be lost forever. Later, a few surviving frogs were found, and now scientists are working to re-establish them.
The Harding Canyon trout, however, seem unlikely to make such a lucky comeback. Backlin and another scientist searched below the mudslide, hoping to find a few trout that had washed downstream, but came up empty.
Rainbow trout can become protected steelhead if they can get to the open ocean. While moving from freshwater to the ocean, the fish take on a streamlined shape that gives them their name. The process known as anadromy allows the fish to exploit both habitats, and to return to protected upland pools for breeding.
But during the rainbow trout phase, the fish are not protected. The Modjeska reservoir and other barriers prevented the Harding Canyon trout from ever reaching the ocean and gaining that protection.
Backlin said he hopes the example of the Harding Canyon trout will encourage state and federal wildlife agencies to develop emergency plans for isolated groups of animals, so they can be sheltered or moved during times of crisis.
“It seems like a lot of these agencies aren’t prepared to deal with issues on short timelines,” he said. “I think a lot of these agencies should have a contingency plan especially for these rare species, in cases where you do have a unique animal.”
Information from: Orange County Register, http://www.ocregister.com