Monday, April 28, 2008

Fishery Works To Restock Salmon

Fishery Works To Restock Salmon
Mare Island project hopes fish will boost numbers
By SARA STROUD/Times-Herald staff writer
Article Launched: 04/26/2008



Fishery Foundation of California deck hand Troy Winchell directs fingerling salmon from a Fish and Game tanker truck into a floating holding pen off Mare Island. (Sara Stroud/Times-Herald)

Mare Island may seem an unlikely spot for a major wildlife rehabilitation project, but it happens to be the epicenter of an effort to rejuvenate an imperiled salmon population.

Several times a week from April to July, Department of Fish and Game tanker trucks deliver fingerling Chinook salmon from inland river hatcheries for release in the Carquinez Strait. On Mare Island, they're met by a boat crew towing a large holding pen to protect the stunned salmon from predators while they acclimate to the warmer, saltier water.

"It's really been a team effort," said Kari Burr of the Fishery Foundation of California, who manages the acclimation project.

On Friday, Fish and Game technicians left the Feather River hatchery near Oroville before sunup, driving four trucks full of the small fish. Once at Mare Island, they hooked up large plastic tubes to the back of the trucks and sent about 400,000 baby salmon, each three- to four-inches long into the net pen waiting in the water below.

"I never get tired of seeing them hit the water," Fish and Game technician Steve Brightwell said Friday.

Trucking salmon from river hatcheries to the bay is nothing new, but this year marks the largest protected acclimation effort to date - 20 million fish transitioned this year, twice as many as in 2007. Crews switch things up between Mare Island and nearby unincorporated Selby, to take advantage of tides and confuse predators.

When the fish hit the water, they go into thermal and osmotic shock and hover on the water's surface, making them easy pickings for bass and seagulls. Protecting the fish in net pens while they acclimate increases the survival rate 500 percent, Fishery Foundation director Trevor Kennedy said.

"I'm glad we're finally doing it to potential. That's a lot of extra fish," Kennedy said

And hopefully those fish will boost a population in such decline that the Pacific Fishery Management Council recently decided to cancel this year's salmon fishing season.

Scientists are studying a long list of possible causes of salmon population collapse. Many researchers point to unusual weather patterns in recent years that have disrupted the marine food chain along the Pacific Coast.

Others blame mismanagement of the water system that has resulted in a lack of fresh water for the migrating fish. Fishermen and environmentalists say too much water is being diverted from the Sacramento-San Joaquin Delta, which juvenile salmon must swim through on their way to the ocean.

"This represents the future of all salmon in the Bay-Delta system," said John Ryzanych, a spokesman for the Bay-Delta Sport Fishing Enhancement Stamp. Anyone fishing from the San Francisco Bay and many inland rivers must buy the $6.05 stamp, which funds the acclimation project. Proceeds go to fishery enhancement projects, including the acclimation project, which costs about $100,000 a year.

This year's fish release won't translate into an immediate salmon boom. It will take about three years for the fish to reach maturity, but starting with the 10 million fish acclimated and released last year, officials are hoping for the best.

"In 2010 it's going to look really good," Kennedy said.

• E-mail Sara Stroud at sstroud@thnewsnet.com or call 553-6833.

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.