Nichols True Klamath salmon infections 2007 report 122607

Our Klamath Basin Water Crisis
Upholding rural Americans' rights to grow food,
own property, and caretake our wildlife and natural resources.

Release of report tracking the tremendous impact of disease on Chinook and Coho salmon in the Klamath River mainstem. (These diseases are largely fatal.)

Marcia H. Armstrong, Supervisor Siskiyou County

http://www.fws.gov/arcata/fisheries/reports/technical/Klamath%20Fish%20Health%20Monitoring%202006%20-%20Final%20Dec%202007.pdf

Nichols K and K True. 2007. FY 2006 Investigational Report: Monitoring incidence and severity of Ceratomyxa shasta and Parvicapsula minibicornis infections in juvenile Chinook salmon (Oncorhynchus tshawytscha) and coho salmon (Oncorhynchus kisutch) in the Klamath River, 2006. U.S. Fish & Wildlife Service California-Nevada Fish Health Center, Anderson, CA.

SUMMARY
The weekly incidence of Ceratomyxa shasta and Parvicapsula minibicornis infection in
juvenile Klamath River Chinook Salmon was monitored over 24 weeks of the spring and
summer out- migration period (March – August) during 2006. The prevalence of both C. shasta
(35% by QPCR) and P. minibicornis (83% by QPCR) during the height of juvenile Chinook outmigration
(May, June and July) was lower in 2006 compared to previous studies in 2004 and
2005. Incidence (by QPCR) of both parasites peaked on 10 July at 93% for C. shasta and 100%
for P. minibicornis. While peak prevalence of infection was still similar in magnitude to
previous monitoring years, peak infection prevalence for both parasites was delayed in 2006.
Among marked hatchery Chinook recovered in the Klamath incidence of C. shasta peaked at
65% in the third week following release from IGH while only 1% of TRH fish were infected.
Infections with both parasites were observed in juvenile coho salmon, with 3% Cs and 48% Pm
incidence in yearling and 7% Cs and 59% Pm incidence among naturally produced young of the
year coho salmon utilizing the mainstem Klamath River.