Heat blamed for Klamath River
fish kill
Dylan Darling
Freelance Writer
July 29, 2005
KLAMATH FALLS, Ore. – Thousands of fish died
last week on a stretch of the Klamath River downstream from U.S.
Bureau of Reclamation irrigation diversions. Officials blamed hot
water and said they can’t alter project operations to ease the risk
to fish.
Among the dead were some endangered sucker fish, but most victims were
tui chubs and fathead minnows.
The die-off apparently started July 18 during evening hours after high
daytime temperatures warmed the water on a seven-mile stretch of the
Klamath from Lake Ewauna at Klamath Falls. Afternoon high temperatures
were above 90 degrees five days in a row.
Roger Smith of Oregon Department of Fish and Wildlife said the dead
suckerfish were concentrated near the U.S. Bureau of Reclamation’s
Lost River Diversion Channel just south of Klamath Falls. Smith said
suckers can tolerate 75 degree water for quite some time, but it harms
their health.
Fish die-offs are common summertime occurrences that happen because of
a combination of low water and high temperatures. When temperatures go
up, the water quality goes down because oxygen levels are lowered by
decaying algae, Smith said.
Temperatures moderated after July 21, and no more fish casualties were
reported early this week.
Rae Olsen, spokeswoman for BuRec’s Klamath Project, said last
week’s fish die-off won’t change how the project is managed. A
biological opinion designed to protect the sucker fish requires
maintaining levels in Upper Klamath Lake, above the irrigation
diversions.
“The most frustrating thing about this is there is nothing we can
do,” Olsen said
