
A record run of adult steelhead, 707 so far, has returned to the California Department of Fish and Wildlife's Mokelumne River Fish Hatchery this year, but most of these fish appear to be fish that stayed in the river rather than going to sea.
“Ninety percent of the fish are adult steelhead in the 18 to 22 inch range averaging 3 pounds each,” said William Smith, hatchery manager. “Most of the fish have summered over in the river, due to the favorable cold water conditions over the past couple of years. We’ve also seen a few larger fish in the 5 to 6 lb. range that have apparently been to the ocean.”
While the flows haven’t been high in the river over the past couple of years, as they are now, the water temperatures have been favorable, due to the EMBUD’s management of cold water releases from Lake Pardee into Lake Camanche in recent years.
“Regardless of whether these fish have been to the ocean or not, any of the offspring of these fish have the potential to go to sea,” noted Smith.
The numbers of steelhead returning to the Mokelumne River Fish Hatchery don’t compare to those at Nimbus, Feather and Coleman fish hatcheries in good years, where the fish number in the thousands, but they are a vast improvement over many years when no adult steelhead returned to the facility.
No steelhead came back to the hatchery, located on the river right below Camanche Dam, for 10 years from 1976 through 1986. Again in 1998-1999, no adult steelhead returned to the facility.
That doesn’t mean that there weren’t any rainbows in the river during these years. The river hosted a popular resident trout fishery for fly, bait and lure anglers, but relatively few of the 100,000 steelhead yearlings released every year went to saltwater and returned.
The river, before the listing of the Central Valley steelhead under the Endangered Species Act (ESA), was managed as a catchable trout fishery, rather than as a wild steelhead or trout river. The CDFW regularly stocked the river with catchable size