|
We Need to Bring Back the Steelhead
The Santa Clara River used to be quite a fishing spot. Pictures from the 1930's show happy fishermen holding bounteous catches of the local southern California steelhead trout that used to frequent our river. Now this migrating fish that traveled as far upstream as Sespe, Hopper and Piru Creeks to spawn, has nearly disappeared from our local waters. Like conservationists in every part of the country, we would like to see them return.
Why should we care about the disappearance of the steelhead? These fish are a form of rainbow trout that are the product of an evolutionary process, requiring centuries, that has allowed them to adapt to the highly intermittent flows of rivers in semi-desert southern California. Like the salmon, they migrate to the ocean and return to the river from which they were spawned - but unlike the salmon, they may go to sea and return more than once. They are not only tremendous fighters that thrill fishermen, but also are a keystone species that reflect whether or not river ecosystems, like the Santa Clara, are in a healthy condition.
A recent steelhead recovery plan outline by the National Marine Fisheries Service (NMFS), released in September 2007, makes it abundantly clear that steelhead populations have declined for a number of reasons. These include the alteration of natural streamflows, physical impediments to fish passage including dams and culverts, stream sedimentation, pollutant discharges into waterways, the spread of non-native species, and the loss of river estuary habitat. California has lost over 90% of its original estuarine habitat, necessary to the steelhead for both rearing and acclimation to salt and fresh water.
Factors that have combined to cause significant reductions in steelhead populations in the southern California coastal area include human activities related to water development, flood control programs, agricultural activities and mining. On the Santa Clara, the Freeman Diversion near Santa Paula has acted as a primary fish passage impediment. The facility has a fish ladder but it is not doing the job – apparently because of insufficient flow levels for long enough time periods after storm events when the steelhead are attempting upstream migration.
On November 8, 2007, in a follow-on document that could have major effects on future operations at Piru Creek's Santa Felicia Dam by the United Water Conservation District, the NMFS issued a draft biological opinion concluding that future operation of the dam in the proposed manner could jeopardize the existence of the southern California steelhead. Proposed changes in flow releases from the dam could impede migrating steelhead from transitioning the Santa Clara River migration corridor. The report recommended, among other things, that United Water study ways of getting steelhead around the dam so they could reach their historic spawning grounds in upper Piru Creek.
United Water recently authored newspaper articles indicating they believe hatchery-raised fish (rainbow trout, not steelhead) may have had a substantial impact on native steelhead populations and that former steelhead plantings from northern California streams may have been responsible for former steelhead population levels in the Santa Clara River.
However, the best scientific information available indicates that, although there has been minor introgression of stocked fish populations into native steelhead populations, decline of the now-endangered steelhead cannot be ascribed to hatchery practices. Extensive studies of trout strains above and below Santa Felicia dam have been carried out by the National Oceanic and Atmospheric Administration's Southwest Fisheries Science Center. These studies have shown conclusively that there is little genetic similarity between hatchery trout strains (or those of northern California populations) and Santa Clara River fish populations.
Recovery of steelhead runs in the Santa Clara River has long been a top priority for the Friends of the Santa Clara River. The southern California steelhead was listed as endangered about 10 years ago. Since then, there has been a plethora of meetings, discussions, issuance of formal and informal documents, and studies. But as evidenced by the fact that only a handful of adult steelhead have been observed in the Santa Clara River in recent years, effective action has not ensued
Friends believe it is way past time to take the appropriate action. Since still more studies are apparently needed and recommended by the federal agencies, those should begin immediately. But they should be accompanied by several actions already recommended in existing reports that would at least begin a process giving this iconic southern California fish a fighting chance to recover, not only in the Santa Clara River, but also in other southern California streams where it has been historically present.
|