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    Tanker truck used to transport fish.

    CDFW staff with tanker truck used to transport smolts

    Sportfishing boat on San Francisco Bay.
    The Salty Lady sportfishing boat hosted Richmond youth

    Smolts being released into bay through pipe.
    Smolts being released into Richmond Harbor

    Image of pipe used to transport fish from tanker truck.

    Scientist on top of tanker truck.

    Fall-run Chinook salmon smolt.
    Fall-run Chinook salmon smolt

    Moments after the sun set on Richmond Harbor’s Brickyard Cove on June 19, CDFW and its partners released approximately 200,000 hatchery raised juvenile fall-run Chinook salmon (known as smolts) into the bay.

    The release was part of a larger effort to truck approximately 19.7 million fall-run Chinook salmon to locations in the San Francisco Bay, San Pablo Bay and lower portions of the Sacramento-San Joaquin Delta. CDFW has two more smolt releases planned for the week of June 20. Since beginning the effort in mid-April, staff have completed three to six releases per week.

    Sunday night’s release was a collaboration with the City of Richmond, Golden State Salmon Association and Richmond Police Athletic League. The team invited a group of young people from Richmond to watch the release from a 56-foot sportfishing boat called The Salty Lady, the use of which was donated for the event to offer youth a glimpse into fishery operations.

    “These kids definitely got a unique opportunity and a front row seat to watch this release,” said Senior Environmental Scientist Jason Julienne, supervisor over CDFW’s North Central Region hatcheries. “I hope it gets them interested and excited for fish and fishing, with the hopes of catching one of these fish when they return as adults in a few years.”

    The goal of the releases is to improve survival of the salmon smolts by helping them bypass 50 to100 miles of hazardous river conditions caused by three consecutive years of drought in the Central Valley. CDFW fisheries biologists tracked flows and water temperatures in the fish's usual migration corridors and recognized that survival would be a challenge without intervention.

    “We want to help ensure some of these fish survive to contribute to commercial and recreations fisheries, as well as hatchery and natural area production in the coming years,” said Julienne.

    The smolts, raised at CDFW’s Feather River Fish Hatchery in Oroville, were eight to 10 months old when released. At that age, the smolts are developmentally ready to handle the salinity of bay waters. The Brickyard Cove location in Richmond was chosen because of its favorable tides and proximity to deep waters.

    “We try to use outgoing tidal movements and the cover of darkness to help get these fish oriented in the right direction toward the Pacific Ocean, and reduce predation,” said Julienne.

    All fish from yesterday’s release were marked and implanted with coded wire tags so CDFW can track their returns and determine how they contribute to fisheries and production in coming years.

    For more information read CDFW’s news release on the trucking operation.

     

    Categories:   Science Spotlight

    Lake with vegetation in foreground. Snowy mountains and green trees in background.
    A long, wet winter has been good for Junction Reservoir and CDFW’s Kamloops rainbow trout that live there.

    Dock on lake with small fishing boats. Mountainside with trees in background.
    The June Lake Marina graciously offered up its net pens to CDFW’s Kamloops rainbow trout program when the drought forced CDFW to rescue its brood stock from a shrinking Junction Reservoir.

    Two men in CDFW uniforms standing in concrete and metal structure in stream. One man is holding a large white net. Trees and patchy snow covered ground in background.
    CDFW hatchery staffers Jimmy Sparks, left, and Drew Klingberg prepare to sex and sort Kamloops brood stock for later spawning, separating males from females as well as those females ready to spawn immediately versus those that need more time to ripen. The fish are returned to Junction Reservoir after spawning.

    Person wearing blue gloves holding net with fish over metal basin with water.
    The offspring from these Kamloops will be raised at CDFW’s Fish Springs Trout Hatchery and stocked by airplane as fingerlings into backcountry waters across the state approved for trout stocking.

    Blue-gloved hands holding small fish over metal basin filled with water and fish.
    Resplendent in their spring spawning colors, Kamloops rainbow are raised and bred for their hard-fighting ability and wild nature that allows them to thrive in California’s remote backcountry waters and provide a thrill for anglers who catch them.

    Junction Reservoir in Mono County is CDFW’s brood lake for the Kamloops rainbow trout, a hard-fighting strain originally from the Kamloops region of British Columbia.

    The 20-acre lake sits on a private cattle ranch off-limits to fishing. It provides a secluded setting for the brood stock, whose progeny are used almost exclusively for the aerial stocking of backcountry waters throughout the state.

    “We try to keep them raised in a more wild condition so they do better in the wild,” said Hot Creek Trout Hatchery Manager Mike Escallier. “They are a really fun fish to catch. They jump a lot. They will jump 3 feet out of the water when you hook one.”

    And Junction Reservoir has never looked better. This spring, the lake was filled to the brim after a long, cold, wet winter. Near the mouth of the lake’s one small inlet, Kamloops were staging for a spawning run, their feisty nature on full display in the clear waters, breaking the surface occasionally and fighting each other over territory.

    Kamloops further up the inlet were blocked from moving upstream by a concrete and metal trap. That’s where CDFW’s hatchery staff collect and sort the fish each spring, spawning them manually to produce the offspring that will be deposited as fingerlings this summer by airplane into backcountry waters approved for stocking.

    The entire scene is a welcome sight after California’s drought nearly collapsed CDFW’s backcountry fish-stocking program. During the darkest days of the drought, the small inlet feeding into Junction Reservoir dried up. Combined with the years-long shortage of rain and snow, Junction Reservoir withered to about half its size. In 2013, CDFW conducted an emergency fish rescue to save about 2,000 of the brood fish and its backcountry trout stocking program altogether.

    The rescued fish were relocated to CDFW trout hatcheries and other nearby waters for safe-keeping. The owners of the June Lake Marina provided a major assist, offering up some of their net pens on June Lake to CDFW and its Kamloops at no charge. The June Lake net pens continue to hold some Kamloops, which CDFW spawns each spring until the program transitions back fully to Junction Reservoir and CDFW’s Fish Springs Trout Hatchery south of Big Pine where the baby Kamloops are raised.

    CDFW returned brood fish to Junction Reservoir in the spring of 2017 following a wet winter and heavy snowpack. CDFW is rebuilding production toward its annual goal of collecting and fertilizing 1.4 million eggs. Some of the offspring are put back into Junction Reservoir to add genetic diversity and different age classes to the rebuilding brood population as no natural spawning occurs in the lake.

    One benchmark hatchery managers and biologists are striving toward is the return of Kamloops to Crowley Lake, where more anglers will have a chance to enjoy them.

    Before the drought wreaked havoc on CDFW’s Kamloops program, a portion of the Kamloops produced each year were allocated to Crowley Lake. While the backcountry trout are sterile – or “triploid” – the fish stocked into Crowley are “diploids” capable of spawning naturally.

    “They spawn at different times than other strains of rainbow trout,” explained Escallier. “They give anglers fishing the creeks opportunity. They tend to be running up the creeks from Crowley right around the trout opener.”

    CDFW Photos. Top Photo: The inlet to Junction Reservoir is blocked by a fish trap where CDFW hatchery employees catch fish in the spring for spawning.

    ###

    Media Contact:
    Peter Tira, CDFW Communications, (916) 322-8908

    Categories:   General

    Concrete fish ladder along hillside and river. Hills in background.

    Blue sign with red spray-painted text reading 'house spawning'

    Fish splashing in water between gate and metal examination chute.

    Two people in yellow rain jackets in hatchery facility alongside fish chute filled with fish.

    At Iron Gate Hatchery in Hornbrook, the fall 2018 spawning operation has just concluded. Iron Gate spawns both Fall-Run Chinook Salmon and Coho Salmon from the Klamath River. For Chinook, the hatchery staff manually collect the eggs and mix it with the milt immediately after the fish come into the facility. CDFW environmental scientists also collect heads from adipose fin clipped salmon, in order to retrieve implanted tags in the snout. The retrieved tags tell the biologists which hatchery the fish is from, and when it was released. They also collect scales, which enable them to determine the age of the fish.

    For Coho Salmon, the process is a little more involved. The Coho are measured and samples taken, but the samples are sent off to a National Oceanic and Atmospheric Administration (NOAA) laboratory in Santa Cruz for analysis. While the samples are processing, the fish are kept in individually-numbered holding tubes at the hatchery. They will be spawned after the tissue analysis determines which fish are the best genetic match.

    CDFW Photos

    For more information about Iron Gate Hatchery, please visit: www.wildlife.ca.gov/Fishing/Hatcheries/Iron-Gate.

    Media Contact:
    Kirsten Macintyre, CDFW Communications, (916) 322-8988

    Categories:   General