• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Scientists to Visit Lake for Hatchery Virus Clues: Samples From Fish Caught at Folsom to Be Tested for Link to Nimbus Outbreak.

Posted on: Friday, 16 June 2006, 15:00 CDT

By Edie Lau, The Sacramento Bee, Calif.

Jun. 16--An investigation into a disease outbreak at Nimbus Fish Hatchery this spring will bring state scientists to Folsom Lake on Saturday looking for blood.

Fish blood, that is.

Tresa Veek, an associate fish pathologist, will be at Granite Beach with colleagues from the Department of Fish and Game asking anglers for blood, tissue and organ samples from salmon and trout they catch that morning.

Fish and Game officials will collect the samples, a process that should take about five minutes, Veek said; all fishermen need do is bring over live fish, or fish that have been preserved on ice.

Veek said live fish are preferred because blood coagulates quickly in dead fish. She noted that salmon and related fish are not supposed to be kept live after being caught, but wardens will make an exception to the rule to support the investigation.

The department is trying to determine the source of the virus that caused an epidemic of infectious hematopoietic necrosis, which killed about 2 million juvenile chinook salmon at the hatchery this spring.

The outbreak is now largely over. The roughly 3 million survivors are being transferred to San Francisco Bay, said Bob Burks, hatchery assistant manager. The juveniles swim out to sea, where they spend two to five years before returning inland to spawn.

However, more disease outbreaks in the hatchery could be in the cards if the virus entered Nimbus via the American River from fish planted by the state in Folsom Lake.

The virus is endemic to California and may be harbored by healthy adult salmon and trout. Scientists will be able to tell if that's the case in Folsom by looking for antibodies in the blood.

"We really want to know whether we can expect to get infected again next year," Veek said. "If it's in the water supply (of the hatchery) and there are plenty of hosts in the lake ... we could be infected for two, three years in a row."

Another possibility is that the virus was introduced by salmon that swam in from the ocean last year to spawn. As happens every year, hatchery workers brought those fish into the facility to collect their sperm and eggs.

"If it was something we did, we can be extra-careful in our procedures in spawning, and hopefully this will never happen again," Veek said.

Department officials say the virus causes illness only in certain species of salmon and does not make people sick, neither by coming in contact with the germ nor by eating fish that have been infected.

Veek said the sampling station will be set up from 9 a.m. to 1 p.m. Saturday on the grassy area at the north end of Ramp B. To reach Ramp B, take Douglas Boulevard east to the lake entrance, pass the kiosk, and turn right at the second stop sign.

-----

Copyright (c) 2006, The Sacramento Bee, Calif.

Distributed by Knight Ridder/Tribune Business News.

For reprints, email tmsreprints@permissionsgroup.com, call 800-374-7985 or 847-635-6550, send a fax to 847-635-6968, or write to The Permissions Group Inc., 1247 Milwaukee Ave., Suite 303, Glenview, IL 60025, USA.

Source: The Sacramento Bee

More News in this Category