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Fishery Bulletin 90(1), 1992 



and provide estimates for heterozygosity, allele fre- 

 quencies, and genetic identities as used for optimum 

 estimation of stock composition of mixed fisheries. 



Materials and methods 



Samples 



A total 37 samples of juvenile chinook salmon were col- 

 lected from northern California and southern Oregon 

 during 1987-88 (Fig. 1, Table 1). Fifteen of these 

 samples were from fish hatcheries and pond rearing 

 projects. All the samples represented fall-run fish with 

 the exception of the upper Sacramento sample (#33) 

 which represented winter run salmon. To collect out- 

 migrant chinook salmon from the wild, two fyke nets 

 (1.5x2.1 X 15m) were placed in a stream approximately 

 1.6km apart and allowed to set overnight. Juvenile 

 salmon were removed from the nets the following mor- 

 ning and frozen on dry ice. Juvenile chinook from 

 hatcheries were collected with dip nets. A small number 

 of salmon was taken from each raceway that contained 

 salmon until a total of 200 fish was collected. At the 

 laboratory, liver, muscle, heart, and eye tissue were 

 removed from 100 fish from each collection, placed in 

 individual tubes, and stored at -80°C. The remaining 

 100 salmon were frozen at -80°C in an archival 

 collection. 



Electrophoresis 



Tissue preparation and horizontal starch-gel electro- 

 phoresis followed standard procedures (Aebersold et al. 

 1987). Gels were made with 12% hydrolyzed potato 

 starch (Connaught Labs.) and one of the following 

 buffer solutions: CAM, an amine citrate buffer from 

 Clayton and Tretiak (1972) adjusted to pH 6.8; TBCL, 

 the discontinuous buffer system of Ridgway et al. 

 (1970) at pH 8.0; TC-4, a Tris citrate buffer of 0.223 

 M Tris, 0.083 M citric acid pH 5.8 as electrode buffer, 

 and a 3.7% mixture of buffer in distilled water for the 

 gel (Schaal and Anderson 1974); and TG, a Tris glycine 

 buffer of 0.025 Tris and 0.192 glycine pH 8.5 for both 

 gel and electrode buffers (Holmes and Masters 1970). 

 The protein systems analyzed, locus designations, 

 tissue distribution of isozymes, and buffer systems used 

 are presented in Table 2. Because of recent changes 

 in genetic nomenclature (Shaklee et al. 1990a), other 

 locus name synonyms are presented in Table 2 to 

 facilitate comparisons with other studies. Allele desig- 

 nations followed Allendorf and Utter (1979). 



Histochemical staining procedures followed Shaw 

 and Prasad (1970) and Harris and Hopkinson (1976). 

 The data set described herein constitutes baseline data 



Figure 1 



Collection sites of 37 samples of chinook salmon Oncorhyn- 

 chus tshawytscha. Identification numbers are defined in 

 Table 1. 



reported in Gall et al. (1989) and used in maximum- 

 likelihood estimates for the California mixed ocean 

 salmon fishery (Brodziak et al. 1992). The duplicated 

 isoloci AAT-1,2, IDH-3,4, MDH-1,2, MDH-3,4, and 

 PGM-3,4 each were treated as two loci. Variant alleles 

 were preferentially assigned to one locus, whereas 

 common alleles were assigned to the other (Gharrett 

 et al. 1987). Variation at the IDH-3,4 isoloci was 

 ascribed to specific loci as described by Shaklee et al. 

 (1990b). Our method of scoring isoloci is not the method 

 of choice for studies of genetic mechanisms, as it may 

 not reflect the true genetic distribution of alleles 



