Monday October 10, 2022
SF Gate —
It’s been just over a year since a century-old dam was removed from Mill Creek, a tributary that runs through the Santa Cruz Mountains in Central California. Now, scientists say the creek is already beginning to show signs of revitalization — including an unexpected discovery.
Aquatic ecologists with the Sempervirens Fund, one of the conservation groups that co-owns the 8,532-acre forest known as San Vicente Redwoods, found 12 juvenile steelhead trout and 15 federally endangered coho salmon fry swimming in the creek last month. It was the first time the latter species had ever been recorded there.
Previously, the deserted dam had been preventing the migratory fish from swimming upstream. It also trapped the granite sediment that provided spawning beds for salmon.
“We didn’t expect to see any coho in Mill Creek,” the Sempervirens Fund’s senior land stewardship manager Ian Rowbotham said in a news release, which noted that a coho salmon was the very first fish they found in the creek that day. “They had never been documented there before.”