58 



Fishery Bulletin 88(1). 1990 



All interesting feature of the catch distribution of fail 

 and spring chinook salmon in Coos Bay (Fig. 3) is that 

 when the catch of fall chinook salmon was highest at 

 the downbay station 1 (20 June-29 July), the catch of 

 spring chinook salmon at this station was low. Con- 

 versely, when the catch of spring chinook salmon was 

 high at the upbay station 5 (29 June-7 July), the catch 

 of fall chinook salmon at this station was relatively low. 

 Later in the summer when most spring chinook salmon 

 were released, fewer fall chinook salmon were caught 

 in the bay. Apparently peak abundances of juvenile fall 

 and spring chinook salmon differed in time and place. 

 The potential for competition between these two stocks 

 was probably greatest in June and July after the large 

 release of spring chinook salmon and when large num- 

 bers of fall chinook salmon were present in shallow 

 nearshore areas of the bay. However, since the two 

 groups were found at different sites, direct competi- 

 tion may have been limited. 



Acknowledgments 



We thank Karl Brookins for his skillful boat handling 

 and beach seining, Mr. and Mrs. Jack Brookins for their 

 kind hospitality, and Alton Chung. Matt Wilson, Ann 

 Raich, and Karen Young for their help during sampling 

 operations. Ron Gowan and Dan VanSlyke of Anadro- 

 mous, Inc. and Reese Bender and Tom Rumreich of 

 Oregon Department of Fish and Wildlife (ODFW) pro- 

 vided information on sampling and hatchery releases 

 of fish in Coos Bay. Jay Nicholas of ODFW and two 

 anonymous reviewers provided helpful comments on 

 the manuscript. This research was funded by the 

 Northwest and Alaska Fisheries Center (Contracts 

 NA-85-ABH-00025 and NA-87-ABH-00014), National 

 Marine Fisheries Service, NOAA. 



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