SEAWARD MIGRATION OF CHINOOK SALMON. 



31 



A somewhat larger coUection of yearlings was made May 10, 1916, at Crandall's 

 seining ground on Griras Island. Thirty -nine specimens were taken here — 16 males and 

 23 females. The males average 106 mm. in length, and the females loi.i mm. All of 

 these fish have the characteristic marginal band of wider rings on the scales. The table 

 (26) follows: 



Table 26. — Data for 39 Chinook Yearlings from Crandall's Seining Ground, on Grims Island, 



May 10, 1916. 



Length. 



Number. 



Scale record. 



Average number of 

 rings— 



To inter- 

 mediate 



growth. 



Total. 



Average length of 

 anterior radius — 



To inter- 

 mediate 

 growth. 



Total. 



Average 

 estimated 

 length of 



fish at 

 bejrinning 

 of inter- 

 mediate 

 growth. 



131 to 135 mm. 

 116 to 120 mm. 

 Ill to IIS mm. 

 106 to 110 mm. 

 101 to 105 mm. 

 96 to 100 mm . . 

 91 to 95 mm. . . 

 86 to 90 mm . . . 

 Si to 85 mm. .. 



Av, loj mm . 



16.0 

 16.6 

 16.0 



14-1 

 16.3 

 15-3 

 IS- 3 

 12.9 



20. S 

 al.9 



21-3 

 19-2 



20-7 



19.9 



18.9 

 17-6 

 20.0 



53-0 

 46.3 



48.0 



41. 

 43- 

 33- 

 33- 



65.5 

 68.0 

 67.0 

 57-0 

 59.5 



ss-s 



54-5 

 49- S 

 53-0 



100.5 

 74-6 

 81. I 

 76.1 

 73.0 

 75-5 

 71-3 

 62.3 

 53.0 



58.5 



74.0 



Eight speamens of yearlings were taken May 11, 1916, at Point Ellice and two at 

 Tenasillihee Island. (See Table 27.) These are quite similar to the fish contained in 

 the collection from Crandall's seining ground, although they average somewhat larger 

 in size. 



Table 27. — CmNOOK Yearlings from Point Ellice and Tenasillihee Island, May ii, 1916. 



One yearling chinook was captured in the Columbia River just above the mouth 

 of the Little White Salmon River on May 25, 1916. This specimen is a female, 98 mm. 

 long. The scales show three rings of the new growth of the second year. The first 

 year's growth comprises 1 5 rings. The anterior radius measures 45 mm. to the beginning 

 of the new growth, and the total length is 59 mm. The estimated length at the time of 

 beginning the new growth is 75 mm. 



