Archive for sockeye salmon

World’s first sockeye raised in land-based fish farm

Metro News
March 28, 2013

With three giant, aluminum pools brimming with thousands of sockeye salmon, a Surrey, B.C., company has become the first in the world to successfully raise the quintessential west coast species in a land-based fish farm — a methodology heralded as one solution to a host of problems associated with the salmon farming industry.

Willowfield Enterprises spent the past 15 years perfecting the farming technology and raising the brood, but will gut, scale, package and sell its first batch of sockeye next week, according to Don Read, the company’s owner.

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Salmon Navigate Home by Earth’s Magnetic Field

Salmon navigate by magnetic field

The epic migrations of salmon have long been a subject of mystery and amazement. What directs these animals’ journeys across great stretches of ocean, pulling them back to the very stream where they were born? Chemical cues help fish pinpoint their stream of origin (Johnsen and Hasler 2006), but what steers the salmon’s course when it is still thousands of kilometers away? A group of fisheries scientists recently offered the first empirical evidence that salmon navigate using the Earth’s magnetic field. The study’s findings, published in the journal Current Biologylast month, suggest that salmon form an imprint of the magnetic field in their natal streams, and find their way back as adults via a route that matches the magnetic memory of their birthplace.

Scientists have hypothesized that migrating animals travel by the magnetic field (Lohmann 2008), but this is difficult to test directly. The authors of the new study devised a natural experiment using 56 years of fisheries records of sockeye salmon (Oncorhynchus nerka) returning to British Columbia’s Fraser River. Fish from the Fraser River typically migrate to Alaska’s Aleutian Islands, spend two years foraging, then embark on the long trek back to the river to spawn. Along the way, they encounter a major roadblock: Vancouver Island obstructs direct entrance to the Fraser River, forcing salmon to detour to the north or south. The scientists predicted that natural shifts in the Earth’s magnetic field from year to year would lead salmon to adjust their route accordingly, choosing the passage with a magnetic field more closely aligned with the magnetic field of the Fraser River two years previously. The team modeled variations in the Earth’s magnetic field based on its intensity and inclination, or the angle of intersection with the Earth’s surface. They matched this up with a long history of fisheries records that documented how many salmon travelled via the northern route each year, which lies solely in Canadian waters, or via the southern route, which is shared by Canadian and U.S. fisheries.

The scientists found that whether the fish turn right or left is far from an arbitrary decision: their selection largely depends on how closely the magnetic field at the route’s entryway resembles the magnetic field they experienced at birth. Sea surface temperature also played a big role: in warmer years, more fish followed the northern, cooler route. Results indicated that 68% of the variation in the salmon’s choice of direction was explained by variation in the magnetic field, sea surface temperature, or some combination of the two. This study suggests that salmon may follow a magnetic “map” to direct their long-distance migrations, then switch to using chemical cues to home in on a specific stream–similar to the way we may use a GPS system to navigate on long road trips, then switch to following visual landmarks as we get closer to home. The authors say this study could explain why hatchery fish sometimes have trouble finding their way back to spawn: imprinting on a hatchery’s human-created magnetic field of electrical wires and iron-reinforced fish tanks could render the fish directionally challenged. 

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The extraordinary effort to save sockeye salmon

Seattle Times
By Lynda V. Mapes
November 17, 2012

A vermilion slash in clear, cold water, the Snake River sockeye in this mountain stream is one of nature’s long-distance athletes, traveling at least 900 miles to get here.

That this fish can make such a journey — the longest of any sockeye in the world — is remarkable. But it’s more incredible that this fish is still around at all.

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Salmon inquiry ignores native poaching

Financial Post
By Vivian Krause
November 5, 2012

Wild salmon are sacred in British Columbia, so expectations were high last week when the Cohen commission delivered its final report on a $26-million, three-year inquiry into the decline of the Fraser River sockeye, B.C.’s most famous fish.

Two of the worst risks to wild salmon are climate change and high-seas overfishing. These international issues are important but hard to tackle, so it was hoped that the commission would also come up with practical positions on issues well within Canada’s jurisdiction, such as inshore poaching and potential disease from fish farms. The commissioner, Justice Bruce Cohen, advised that preventing illegal fishing should be a “priority consideration,” but that didn’t get anywhere near the same emphasis as his crackdown on fish farms.

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Commission presses Ottawa to curb fish-farm impact on sockeye

The Globe and Mail
October 31, 2012

The event that caused Prime Minister Stephen Harper to order a judicial inquiry into salmon management was so catastrophic it sent a shock wave throughout British Columbia: In the fall of 2009, sockeye salmon almost vanished from the Fraser River.

After decades of decline, the most productive salmon river on the planet – a river that once had a run of 100 million sockeye – had suddenly been reduced to just one million spawners.

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Salmon probe shows need for reform, group says

The Globe and Mail
October 28, 2012

Some who took part in the inquiry looking into why millions of sockeye salmon vanished from one of British Columbia’s most prized fisheries are already anticipating what the report might say, and many believe the news won’t be good for the Department of Fisheries and Oceans.

After listening to 160 witnesses, compiling 14,000 pages of transcripts and 2,100 exhibits, B.C. Supreme Court Justice Bruce Cohen must deliver his report to the federal government by Monday, although it remains unclear when, or even if, the document will be made public.

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Sockeye regaining ground throughout Columbia region

The Spokesman-Review
By Rich Landers
October 10, 2012

More than a century after their runs up the Cle Elum River were wiped out by dams, the sockeye are spawning again this year, thanks to a boost from fisheries programs.

  • Sockeye also are making renewed appearances in the upper reaches of the Deschutes River basin.
  • And there’s more hope than ever for re-establishing the legacy of sockeyes making the 900-mile run from the ocean to the Snake River headwaters in the Sawtooths.

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Returning salmon to Upper Yakima Basin

The Columbia Basin Bulletin
September 27, 2012

A motherload of sockeye salmon – 1,000 in all – is beginning to fan out into the many tributary fingers that feed central Washington’s Lake Cle Elum, with Yakama Nation biologists chasing them.

Many of the sockeye spawners, trapped at Priest Rapids Dam on the mid-Columbia River, were equipped with acoustic tags before being hauled by truck to the lake and released. The Yakama Nation developed an agreement with Grant County Public Utility District to use its Priest Rapids Dam off-ladder adult fish trap to collect sockeye for the reintroduction effort.

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Most returning Snake River sockeye hatchery origin

The Columbia Basin Bulletin
September 7, 2012

Fisheries officials corralled a total of 34 endangered Snake River sockeye salmon Wednesday in what has become an annual “roundup” of fish balking downstream of a cross-stream weir on the Salmon River in central Idaho’s high country.

The weir at the Idaho Department of Fish and Game’s Sawtooth Fish Hatchery, and one nearby on Redfish Lake Creek, are manned each late summer and fall to capture and evaluate sockeye spawners returning to the Stanley basin. The sockeye are held at Eagle Hatchery near Boise until spawning time.

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Latest Lake Washington sockeye and chinook counts from Ballard Locks

The Seattle Times
By Mark Yuasa
August 3, 2012

The Lake Washington sockeye returns continue to drop off, but chinook are starting to build.

Through Thursday, Aug. 2 the inseason count provided by Mike Mahovlich, a Muckleshoot Tribal biologist, is now up to 144,177 compared to the preseason forecast of 45,871.

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