Migratory characteristics of juvenile 

 ocean-type Chinook salmon, 

 Oncorhynchus tshawytscha, 

 in John Day Reservoir on the 

 Columbia River 



Albert E. Giorgi 



Don Chapman Consultants. Inc.. 7981 

 Redmond. Washington 98052 



I 68th Ave NE 



David R. Miller 

 Benjamin R Sandford 



Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA 

 2725 Montlake Blvd. E.. Seattle, Washington 981 12 



Both stream-type and ocean-type 

 chinook salmon, Oncorhynchus 

 tshawytscha, are found in the Co- 

 lumbia River system. Ocean-type 

 chinook salmon migrate seaward 

 and enter seawater as subyearlings 

 or zero-age juveniles within a year 

 of emergence, whereas stream-type 

 fish reside in fresh water at least 

 one full year before migrating 

 (Healey, 1991). Yearling stream- 

 type chinook salmon migrate 

 through the mainstem Columbia 

 River and its largest tributary, the 

 Snake River, during the spring 

 months (Raymond, 1979). In con- 

 trast, zero-age ocean-type chinook 

 salmon migrate during the sum- 

 mer, but their migration can extend 

 into autumn. Information regard- 

 ing the migratory behavior of 

 ocean-type chinook salmon in the 

 impounded reaches of the Colum- 

 bia River is limited. Early research 

 showed that even during high-flow 

 years, large numbers of zero-age 

 ocean-type chinook salmon re- 

 mained in John Day Reservoir on 

 the Columbia River for a protracted 

 time compared with stream-type 

 chinook salmon (Raymond et al. 1 ; 

 Sims et al. 2 ). 



872 



Hydroelectric development has 

 been identified as an important fac- 

 tor that has contributed to de- 

 creased salmon and steelhead (On- 

 corhynchus spp.) production in the 

 Columbia River Basin (Raymond, 

 1979, 1988; Williams, 1989). Direct 

 mortality of downstream migrant 

 juvenile salmonids is associated 

 with passage through the turbines, 

 spillways, and juvenile bypass sys- 

 tems at dams. Apart from direct 

 mortality, a number of studies have 

 indicated that the creation of im- 

 poundments, altered flows result- 

 ing from electric power demand, 

 and irrigation withdrawals as a 

 result of dam construction have 

 slowed the seaward migration of 

 juvenile salmonids (Raymond, 

 1969, 1979; Ebel and Raymond, 

 1976). 



In an effort to lessen deleterious 

 effects associated with hydroelec- 

 tric dam construction, fisheries 

 managers have developed water 

 management strategies to augment 

 instream flows to provide improved 

 passage conditions for juvenile 

 salmonids during their seaward 

 migration (Northwest Power Plan- 

 ning Council, 1987). Rationale sup- 



porting these actions is based 

 largely on data by Sims and Ossi- 

 ander 3 which described the migra- 

 tory characteristics of juvenile 

 stream-type chinook salmon and 

 steelhead, O. mykiss, within the 

 Snake River and in portions of the 

 Columbia River. They found that 

 increased instream flow volumes 

 during the spring reduced smolt 

 travel time through the hydroelec- 

 tric complex and increased smolt 

 survival. Similar data for ocean- 

 type chinook salmon that migrate 

 during the summer as zero-age ju- 

 veniles are not available. 



Berggren and Filardo ( 1993 ) sug- 

 gested that increased water veloc- 

 ity increased migration speed for 

 ocean-type chinook salmon and led 

 to increased survival by reducing 

 exposure time to predatory fish and 

 to increasing summer water tem- 

 peratures. There is ample evidence 

 that predatory fish, principally 

 northern squawfish, Ptychocheilus 

 oregonensis, are abundant and con- 

 sume large numbers of juvenile 

 salmonids particularly during the 

 summer in John Day Reservoir 

 (Rieman et al., 1991; Vigg et al., 

 1991). However, the relationships 

 between flows, migration rate, and 

 survival are uncertain. 



1 Raymond, H. L., C. W. Sims, R. C. 

 Johnsen, and W. W. Bentley. 1975. Effects 

 of power peaking operations on juvenile 

 salmon and steelhead trout migrations, 

 1974. Northwest Fish. Sci. Cent., Natl. 

 Mar. Fish. Serv., Seattle, WA98112-2097. 

 Report to U.S. Army Corps of Engineers, 

 46 p. 



2 Sims, C. W.. R. C. Johnsen. and W. W. 

 Bentley. 1976. Effects of power peaking 

 operations on juvenile salmon and steel- 

 head trout migrations, 1975. Northwest 

 Fish. Sci. Cent., Natl. Mar. Fish. Serv., 

 Seattle, WA 98112-2097. Report to U.S. 

 Army Corps of Engineers, 36 p. 



3 Sims, C. W„ and F J. Ossiander. 1981. 

 Migrations of juvenile chinook salmon and 

 steelhead trout in the Snake River from 

 1973 to 1979: a research summary. North- 

 west Fish. Sci. Cent., Natl. Mar. Fish. 

 Serv., Seattle, WA 98112-2097. Report to 

 U.S. Army Corps of Engineers, 31 p. 



Manuscript accepted 31 March 1994. 

 Fishery Bulletin 92:872-879. 



