Author: Melo Maiolie
Publisher:
ISBN:
Category : Bull trout
Languages : en
Pages : 68

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Book Description

Author: Melo Maiolie
Publisher:
ISBN:
Category : Kokanee salmon
Languages : en
Pages : 34

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Book Description

Author: Gregg Mauser
Publisher:
ISBN:
Category : Freshwater zooplankton
Languages : en
Pages : 48

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Book Description

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 24

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Book Description
The Bonneville Power Administration (BPA) funded two 4-year research projects to develop recommendations for improving the sport fishery on Dworshak Reservoir. Research began during 1987 as a cooperative effort between the Idaho Department of Fish and Game (IDFG) and the Nez Perce Tribe of Idaho. The Nez Perce Tribe examined smallmouth bass and rainbow trout fisheries. The IDFG evaluated kokanee population dynamics and documented changes in reservoir productivity. 12 refs., 12 figs.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 39

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Book Description
We monitored the kokanee Oncorhynchus nerka kennerlyi population in Dworshak Reservoir, Idaho, by mid-water trawling and counting spawners in representative streams. Our estimates of age 1 kokanee abundance in 1993 were the highest on record; 556,000 fish. These fish resulted from last years record year class of age 0 kokanee. Age 2 kokanee were also abundant, achieving their second highest level on record. Dworshak Dam discharged less water between July 1, 1992 and June 30, 1993 than any of our recent years of study (the lowest since 1986-1987). Based on a past relationship with an r2=0.62, we expected age 2 kokanee abundance to be very high with this low level of discharge. We estimated mature kokanee abundance by trawling, which correlated well (r2=.89) to standardized spawner counts. This gives us the means to convert the older spawner count data into age 2 kokanee estimates. It is also a validation of spawner counts in tributary streams as an accurate method to obtain an index of adult kokanee abundance.

Author: Melo Maiolie
Publisher:
ISBN:
Category : Kokanee salmon
Languages : en
Pages : 39

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Book Description

Author: Eric J. Stark
Publisher:
ISBN:
Category : Dams
Languages : en
Pages : 93

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Book Description
Describes research to test underwater strobe lights to determine their effectiveness at repelling kokanee away from the turbine intakes of Dworshak Dam.

Author: Steve Elam
Publisher:
ISBN:
Category : Hydroelectric power plants
Languages : en
Pages : 39

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Book Description

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 46

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Book Description
A total of 7,071 kokanee spawners were counted during the peak of the spawning run in five tributaries to Dworshak Reservoir during 1987. Both size and numbers of fish were fairly average. During years when numbers of fish were large, total length of age 3+ kokanee was as low as 25 cm. Conversely, small numbers of kokanee resulted in an average length of 37 cm. Zooplankton densities during November of 1987 averaged 17.92 organisms/L, but decreased to 3.96 organism/L during December. These densities are similar to values obtained during 1972, although the percentage of cladocerans in the samples may have declined. Kokanee preferred Daphnia over 1 mm in length. Concentrations of orthophosphate and nitrate appear to have declined since the reservoir filled. Kokanee catch rates for boat anglers changed from 1.4 fish/h during November to 2.7 fish/h during December to 0.0 fish/h during January. This declining trend may have been temperature related. Harvest for these 3 months was an estimated 1,612 kokanee. 10 refs., 13 figs., 4 tabs.

Author:
Publisher:
ISBN:
Category : Fish populations
Languages : en
Pages : 34

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Book Description
We monitored the kokanee Oncorhynchus nerka kennerlyi population in Dworshak Reservoir, Idaho, by mid-water trawling and counting spawners in representative streams. Our estimates of age 1 kokanee abundance in 1993 were the highest on record; 556,000 fish. These fish resulted from last years record year class of age 0 kokanee. Age 2 kokanee were also abundant, achieving their second highest level on record. Dworshak Dam discharged less water between July 1, 1992 and June 30, 1993 than any of our recent years of study (the lowest since 1986-1987). Based on a past relationship with an r2=0.62, we expected age 2 kokanee abundance to be very high with this low level of discharge. We estimated mature kokanee abundance by trawling, which correlated well (r2=.89) to standardized spawner counts. This gives us the means to convert the older spawner count data into age 2 kokanee estimates. It is also a validation of spawner counts in tributary streams as an accurate method to obtain an index of adult kokanee abundance.