ARTIFICIAL PROPAGATION OF THE SALMONS OF 

 THE PACIFIC COAST." 



Revised and enlarged by Henry O'Malley, Field Assistant, U. S. Bureau of 

 Fisheries, in Charge of Operations on the Pacific Coast. 



THE SALMONS OF THE PACIFIC COAST. 



There are five species of salmon on the Pacific coast belonging to 

 the genus Oncorhynchus, namely, the chinook, spring, king, or 

 quinnat salmon {Oncorhynchus tschmcytscha) \ the blueback, sock- 

 eye, or redfish {Oncorhynchus nerka) ; the humpback or pink sal- 

 mon {Oncorhynchus gorhuscha) ; the silver or coho salmon {Onco- 

 rhynchus kisutch) ; and the chum or dog salmon {Oncorhynchus 

 keta). Among the features which distinguish the Pacific salmons 

 from the Atlantic salmon are the larger number of rays in the anal 

 fin and the invariable habit of spawning but once and then dying; 

 the Atlantic salmon may spawn several times. 



The characters noted in the following key will usually be suffi- 

 cient to distinguish the different species of Pacific salmon: 



Chinook salmon. — Scales in longitudinal series, about 135; py- 

 loric cceca, 110 to 200, averaging 150 ; gillrakers comparatively short, 

 from 20 to 25 in number, 9 being above the angle; rays in anal fin 

 from 14 to 19, average 16 ; branchiostegals, 14 to 19, average 16. 

 Body robust; head conic; caudal fin lunate. Color above dusky, 

 sometimes with bluish or greenish tinge; sides and belly silvery; 

 head dark, with metallic luster, back and sides with prominent spots, 

 usually X-shaped. 



Blueback salmon. — Scales in longitudinal series, about 130; py- 

 loric coeca, 75 to 100; gillrakers comparatively long and slender, 

 from 30 to 40 in number; rays in anal fin, 14 to 18; branchiostegals. 

 13 to 15. Body rather slender; caudal fin lunate; anal and dorsal 

 fins low. Color, sides silvery, no spots on back, which is frequently 

 bright blue. 



Humpback salTnon. — Scales very small, 200 or more in longitudinal 

 series; pyloric cceca very slender, about 180 in number; gillrakers 

 short, from 20 to 25 ; anal rays, 15 ; branchiostegals, 11 to 12. Color, 

 bluish above, silvery on sides ; lower part of back, adipose fin, and 

 tail with numerous black spots, largest and of oblong form on tail. 



Silver salmmi. — Scales large, about 130 in longitudinal series; 

 pyloric coeca comparatively few and large, 40 to 110 in number, 



"This paper represents a revision and enlargement of the chapter on "The Salmons 

 ?, tbe Pacific Coast." from the Manual of Fish-Culture, published in the Report of the 

 U. S. Commission of Pish and Fisheries for 1897. a first revised edition of which was 

 published separately in 1900. The chapter was subsequentlv i.ssued in separate form 

 under the title " Artificial Propagation of the Salmons of the Pacific Coast." 



