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• 141. [Image] Klamath River fish die-off, September 2002 : causative factors of mortality

  	Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath ...
  	Citation × Citation Citation Abstract Copy Title: Klamath River fish die-off, September 2002 : causative factors of mortality Author: Guillen, George Year: 2003, 2005, 2004 Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath River, California in September 2002. The proximate cause of death was heavy infections of two fish pathogens, Ich and columnaris. However, given that these ubiquitous pathogens are normally found in the Klamath River, additional factors must have played a role for them to have become lethal. It is our conclusion based on multiple lines of evidence that the fish die-off in the lower Klamath River in 2002 was a result of a combination of factors that began with an early peak in the return of a large run of fall Chinook salmon. Low river discharges apparently did not provide suitable attraction flows for migrating adult salmon, resulting in large numbers of fish congregating in the warm waters of the lower River. The high density offish, low discharges, warm water temperatures, and possible extended residence time of salmon created optimal conditions for parasite proliferation and precipitated an epizootic of Ich and columnaris. Based on a review of available literature and historical records, this was the largest known pre-spawning adult salmonid die-off recorded for the Klamath River and possibly the Pacific coast. Title: Klamath River fish die-off, September 2002 : causative factors of mortality Author: Guillen, George Year: 2003, 2005, 2004 Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath River, California in September 2002. The proximate cause of death was heavy infections of two fish pathogens, Ich and columnaris. However, given that these ubiquitous pathogens are normally found in the Klamath River, additional factors must have played a role for them to have become lethal. It is our conclusion based on multiple lines of evidence that the fish die-off in the lower Klamath River in 2002 was a result of a combination of factors that began with an early peak in the return of a large run of fall Chinook salmon. Low river discharges apparently did not provide suitable attraction flows for migrating adult salmon, resulting in large numbers of fish congregating in the warm waters of the lower River. The high density offish, low discharges, warm water temperatures, and possible extended residence time of salmon created optimal conditions for parasite proliferation and precipitated an epizootic of Ich and columnaris. Based on a review of available literature and historical records, this was the largest known pre-spawning adult salmonid die-off recorded for the Klamath River and possibly the Pacific coast. Close

• 142. [Image] Surface water-supply of the United States. pt. 11. Pacific slope basins in California

  	Includes Klamath River Basin; Chiefly tables; Includes indexes; Prepared in cooperation with the states and other agencies
  	Citation × Citation Citation Abstract Copy Title: Surface water-supply of the United States. pt. 11. Pacific slope basins in California Author: U.S. Dept. of the Interior, Geological Survey Year: 1910, 2008, 2005 Includes Klamath River Basin; Chiefly tables; Includes indexes; Prepared in cooperation with the states and other agencies Title: Surface water-supply of the United States. pt. 11. Pacific slope basins in California Author: U.S. Dept. of the Interior, Geological Survey Year: 1910, 2008, 2005 Includes Klamath River Basin; Chiefly tables; Includes indexes; Prepared in cooperation with the states and other agencies Close