For the first time in decades, fish that appear to be endangered steelhead trout are being sighted in Trabuco Creek, state officials said Tuesday.
Environmentalists and biologists say the finds are significant and raise hopes that the species -- once plentiful in local watersheds but virtually absent since the 1960s -- will make a comeback. Until now, local sightings of the trout have been confirmed only along San Mateo Creek, just south of the county line, where more than 40 steelhead were reported in 1998.
It's unclear whether the discoveries would affect the proposed Foothill South toll road or the planned construction of 14,000 homes by Rancho Mission Viejo in south Orange County.
Two biologists from the state Department of Fish and Game have spotted what were believed to be steelhead three times in Trabuco Creek at the outlet of a massive concrete culvert below Interstate 5 in San Juan Capistrano.
The first sighting came in September 2002 when Mary Larson, a senior fisheries biologist, saw several fish, estimated at 10 to 14 inches long. In May and June of this year, Larson and a colleague spotted three fish longer than 10 inches.
They notified federal officials in late November.
"This is a significant find, in large part because people have not seen steelhead in a long, long time," Larson said. "We're excited about it. We believe we can do some kind of recovery project in the county."
Already, Trout Unlimited of California, a national conservation group with nearly 9,600 members, is working with Fish and Game officials to restore and preserve steelhead trout habitat in Orange County. They have been concentrating on San Mateo Creek, which runs 18 miles from the Cleveland National Forest to Trestles Beach, part of San Onofre State Beach, south of San Clemente.
"As we find more fish and document them, we could turn our attention toward Trabuco Creek," said George Sutherland, who coordinates the steelhead restoration project for the South Coast Chapter of Trout Unlimited.
Larson said she is almost certain that the Trabuco sightings were steelhead because of where they were found, their size, and indications that they were not bred in a hatchery.
Genetic tests to make a confirmation will be performed on samples taken from one fish caught by an angler during Larson's May visit.
Fishing for steelhead trout is not permitted, but in this case the angler's catch proved to have scientific value.
Steelhead look like rainbow trout but are genetically coded to adapt to both fresh and saltwater habitats. They spawn in rivers or creeks, and the young eventually make their way to the sea, where the fish turn a silvery hue.
In 2002, the federal government extended endangered status to steelhead found from Malibu to the Mexican border. Such status mandates that steps be taken to protect the threatened species and its habitat.
Environmental groups, such as the Sierra Club and Friends of the Foothills, contend that confirmation of steelhead trout could affect housing projects proposed for south Orange County and plans by the Transportation Corridor Agencies to build the Foothill South tollway, the final leg of the county's toll road network.
The groups say the Trabuco Creek finds are an indication that steelhead also may exist in San Juan Creek, to the south, which crosses Rancho Mission Viejo land and the proposed path of the Foothill South extension.
Steelhead must swim up San Juan Creek to reach Trabuco Creek, which forks to the north and east. Historians also say San Juan Creek was once an abundant source of steelhead for Indians and other fishermen in the first half of the last century.
"With more trout being found, it raises the question of whether the toll road and new development should occur in the habitat of an endangered species," said Mike Hazzard, an environmental activist in south Orange County.
Fish and Game officials are urging Caltrans to rebuild the concrete culvert upstream from the site where the fish were found, to allow them to swim upstream and spawn.
The structure now is a barrier to the fish.
Larson said, however, that department surveys of the portions of San Juan Creek beyond where it joins Trabuco Creek have not found any steelhead trout because it doesn't appear to be suitable habitat.
A long stretch of San Juan Creek through Rancho Mission Viejo land has yet to be studied by the department. But Diane Gaynor, a spokeswoman for Rancho Mission Viejo, said county, state and federal environmental reviews have not found any evidence of steelhead trout on San Juan Creek on company property.
Clare Climaco, a spokeswoman for the Transportation Corridor Agencies, said the Trabuco Creek site is well west the Foothill South project area and should not affect environmental planning for the project.
Even if steelhead trout are found in the path of the proposed toll road and subdivisions, Larson said, the projects wouldn't necessarily be halted, so long as steps are taken to protect the species.
"We can have development and protect endangered species," Larson said. "They are not mutually exclusive."