[env-trinity] Times Standard: Deadly fish parasite found on Klamath River fish
tstokely at att.net
Fri Jul 24 07:23:20 PDT 2015
- Deadly fish parasite found on Klamath River fish
A steelhead trout caught on a tributary of the lower Klamath River during the September 2002 fish kill shows both a brown-colored infection by the columnaris gill disease and inflamed red gills caused by a deadly parasite known as ich. Both infections were recently found on fish at the same location on Wednesday and are likely caused by low flow conditions, according to local fisheries biologists. Photo courtesy of Michael Belchik
| By Will Houston, Eureka Times-Standard
POSTED: 07/23/15, 9:39 PM PDT | UPDATED: 2 HRS AGO
The deadly signs were expected to surface on the lower Klamath and Trinity rivers this summer, but not this early.
On the lower Klamath River, a survey on six salmonid fish at the mouth of Blue Creek on Wednesday by the Yurok Tribe Fisheries program found the presence of a deadly parasite — the same one responsible for the deaths of tens of thousands of fish on the same river system in 2002.“There is no doubt, we’re in a pretty serious situation,” Yurok senior fisheries biologist Michael Belchik said.
Having witnessed the 2002 fish kill personally, Belchick said this is the earliest he has ever seen an ich infection appear on the lower Klamath River, adding that fisheries biologists returned to Blue Creek for more fish sampling Thursday afternoon.
The parasite, known as Ichthyophthirius multifiliis or “ich,” had also been found on salmonids during a survey last year in September — the first time since the 2002 fish kill. This year it showed up five weeks earlier, Belchik said.
What makes the grain-sized ich so deadly is it attaches to the fish’s gills causing them to swell, eventually suffocating the fish. Warm water temperatures caused by low flows and other factors can stress fish immune systems and make them more susceptible to the parasite and other diseases. For ich, the ongoing four-year drought is prime condition. As fish crowd together to find cooler waters, ich is able to more easily spread.
In a statement released by the Hoopa Valley Tribe, fish biologist Joshua Strange wrote that the low-flow conditions on the lower Klamath River are expected to continue their decline to about 2,000 cubic feet per second — lower than most of the driest years on record for the state and similar to one of the most deadly for fish.
“Flows during the lethal ich outbreak of 2002 were also approximately 2,000 (cubic feet per second),” he wrote.
The fall run of adult Chinook salmon this year is expected to be around 120,000, according to the Pacific Fisheries Management Council. The 2002 run had about 130,000 fish, Strange wrote.
On the Trinity River, Fisheries Director Mike Orcutt for the Hoopa Valley Tribe said ich has not been detected yet, though surveys have not been recently conducted.
However, many salmonids on the river have been found to have severe infections from a deadly gill disease known as columnaris, which can also increase the likelihood of ich infection. Other alarming signs in the Trinity River include elevated toxic blue-green algae and another type of parasite that is particularly deadly to juvenile salmon.
One of the most effective ways of avoiding another fish kill has been to release additional flows from damns on Trinity Lake to cool the waters. Several of such releases occurred last year, including an unprecedented emergency flow release made in September which doubled the flow of the river after the ich infection was detected.
Orcutt said that the Hoopa tribe has received “strong assurances” from the U.S. Interior Department’s Bureau of Reclamation for releasing fish kill preventative flows from Lewiston Dam in Trinity County as it had done for the last three years to prevent such catastrophes. The Hoopa Valley Tribe — with backing from the Yurok Tribe — has requested 63,000 acre-feet to be released most likely in mid-August.
The bureau is currently working on an environmental assessment of such a release. But with Trinity Lake water is also being diverted to the Central Valley Project, Orcutt said irrigators from that area will likely file litigation against the releases as they have done in the past.
“Hopefully the Interior makes the right management decision and is able to defend it in court if necessary,” he said.
Over the last year, the Interior Department has often sided with the North Coast, having released a legal opinion in December recognizing Humboldt County’s long-challenged right to an annual 50,000 acre-feet of Trinity River water to be used for the benefit of downstream users. The Humboldt County Board of Supervisors formally requested the full 50,000 acre-feet in May for the purpose of preventing a fish kill.
Third District Supervisor Mark Lovelace said discussions with the bureau are still ongoing on when this year’s flow should be released and how to develop a regular mechanism on how to make flow requests in the future. Part of the discussions have revolved around whether to include the 50,000 acre-feet in the Hoopa tribe’s flow request, which he said is now more of a serious consideration after the recent fish survey.
“We’d anticipated some months back that we would likely almost certainly be needing these augmented flows again this year,” Lovelace said. “That finding just reaffirms that.”
Meanwhile, the Bureau of Reclamation is currently in the process of allowing the public to vet the environmental impact statement for a long-term plan it is drafting to protect salmon on the lower Klamath River. The bureau will host a meeting in Arcata on Aug. 5 at the Red Roof Inn — 4975 Valley West Blvd. — from 5:30-7 p.m.
Will Houston can be reached at 707-441-0504.
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