each minute of effort. The purse 

 seine effort in 1978 produced 274.8 

 finfish per minute of effort due to 

 a large catch of Pacific herring at 

 Tongue Point while the May 1979 sur- 

 vey averaged 66.4 finfish per minute. 

 Catch results indicated both sub- 

 stantial numbers of finfish and spe- 

 cies diversity at sample sites. Eco- 

 nomically important species were com- 

 mon and included coho salmon, Onco- 

 rhynchus kisutch ; chinook salmon, 0. 

 tshawytscha ; starry flounder, Pla - 

 tichthys stellatus ; American shad, 

 Alosa sapidissima ; and Pacific her- 

 ring, Clupea harengus pallasi . 



A summary of species and num- 

 bers captured at each site is shown 

 in Table 2. Grouped weights are 

 included to provide further assess- 

 ment of catch results. Purse seine 

 catches at the Tongue point site 

 had substantially more pelagic fish 

 than other areas in October and 

 May. Trawl catches revealed the 

 Interstate Bridge site had the 

 highest number of demersal finfish, 

 but many were also found at Tongue 

 Point. The Dungeness crab, Cancer 

 magister , was abundant at Tansy 

 Point. Overall, the catch results 

 indicated Tongue Point had a high 

 biological value in terms of fish 

 and crustaceans. 



Several important finfish spe- 

 cies captured in this study were ex- 

 amined to determine if their sizes 

 and food utilization were comparable 

 between the sample sites. The five 

 species, chinook salmon, Pacific her- 

 ring, American shad, Pacific tomcod, 

 Microgadus proximus , and Pacific 

 staghorn sculpin, Leptocottus arma - 

 tus, represent 66.7 percent of all 

 finfish captured. Shad and herring 

 represent pelagic species while chi- 

 nook salmon occur in both pelagic and 

 intertidal habitats, whereas tomcod 

 and staghorn sculpin are demersal 

 fish. 



Pacific herring populations 

 consisted of at least two age 

 groups in the October 1978 survey, 

 with larger fish in the marine hab- 

 itat and smaller fish at the fresh- 

 water site (Figure 2). The modified 

 Index of Relative Importance (IRI), 

 described by Pinkas (1971), indi- 

 cated herring were actively feeding 

 on calanoid copepods , but only at 

 Tongue Point. In the May 1979 

 survey, a single herring age group 

 predominated at Tansy Point and the 

 Interstate Bridge. Zooplankton 

 was the principal diet though a 

 substantial proportion of fish 

 examined had not eaten. 



American shad were also repre- 

 sented by two distinct age groups but 

 they were present during both surveys 

 (Figure 3) . It was evident the age 

 groups had increased in length sev- 

 eral centimeters between October and 

 May. The IRI indicated the impor- 

 tance of unidentified plant material 

 consumed at the upper three sites 

 during the fall survey. At Tongue 

 Point where most shad were found, 

 however, calanoid copepods were also 

 an important food item. In May 

 1979, shad consumed the benthic 

 amphipod Corophium salmonis and 

 calanoid copepods at Tongue Point 

 and Tansy Point. Copepods were 

 the important identifiable food 

 item at the Interstate Bridge 

 where most shad were captured. 



Chinook salmon length fre- 

 quency and IRI categories are 

 shown in Figure 4. Only subyear- 

 ling fall chinook were encountered 

 in the 1978 survey with most taken 

 at Tongue Point. Identifiable 

 food items at that site were pri- 

 marily insects. The May 1979 chi- 

 nook catch consisted of subyearling 

 fall chinook, yearling spring chinook 

 and a few residuals. Diet of all the 



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