FAUNA OF THE ALEUTIAN ISLANDS AND ALASKA PENINSULA 401 



Figure 22. — Pink or humpback salmon, Oncorhynchus gorbuscha, breeding 

 male. Amchitka Island, August 22, 1938. 



Oncorhynchus gorbuscha, the humpback, or pink salmon is 

 said by Evermann and Goldsborough to be the most common 

 species in Alaska (fig. 22). Some of our specimens were adults, 

 and others were fingerlings caught on hook and line in streams. 

 A parasitic copepod, Lepeophtheirus salmonis, was collected from 

 the back of a humpback salmon on Tanaga Island. 



Oncorhynchus keta, the dog, or chum salmon, was collected only 

 once — on Atka Island. The natives had constructed a crude fish 

 trap at the outlet to Korovin Lake. On August 13, the silver salmon 

 were running and there were also a few dog salmon in the trap. 

 These were not recognized by the natives as dog salmon, but 

 were termed "winter salmon" and were given an Aleut name 

 slightly different from that of the silver. Four specimens ex- 

 amined were males with apparently mature testes but without the 

 external hump that is characteristic of the breeding fish. 



Oncorhynchus kisutch, the silver salmon, was collected on 

 five islands. 



Oncorhynchus nerka, the sockeye, or red salmon, was running 

 into a lake on Attu Island in early June 1937 (figs. 23 and 24). 

 The species runs only into streams that have lakes somewhere in 

 the headwaters. 



Oncorhynchus tschawytscha, known as the king, spring, or 

 Chinook salmon, was collected only in the fingerling stage. The 

 adults frequent deep, or offshore waters, occasionally reaching a 

 size of 100 pounds. They are taken by trolling. 



Oxycottus acuticeps is of the many species of tide-pool bullheads. 



