Figure 2. — Pygmy whitefish from the Naknek system. 

 From top to bottom : 5-year-old mature female, 163 mm. 

 long, collected November 9, 1962, in Soutb Bay ; 2-year- 



old immature female, 98 mm. long, collected November 

 9, 1962, in South Bay ; 3-year-old mature female, 76 

 mm. long, collected November 7, 1962, from Brooks Lake. 



known in Brooks Lake where the greatest sam- 

 pling effort was expended. Pygmy whitefish were 

 collected in all sections of Brooks Lake, and two 

 areas of heavy abundance were found at opposite 

 ends of the lake (areas 1 and 5 (fig. 1)). They 

 also occurred throughout. South Bay and Iliuk 

 Ann. A concentration of this fish apparently oc- 

 curs in the semiprotected bay of South Bay near 

 the mouth of Brooks River and in the upper end 

 of Iliuk Arm. The known distribution of pygmy 

 whitefish in North Arm is spotty, but it is believed 

 to be widely distributed in this basin. In 1962 and 

 1963, small whitefish were not specifically identi- 

 fied on field collection sheets of seine records from 

 that basin. We suspect that at least some of these 

 were pygmy whitefish. In Grosvenor Lake, pygmy 

 whitefish were collected in most areas of the lake; 

 but, in Coville Lake, they were collected only from 

 the east end of the lake. The one Hammersly Lake 



collection was made near the lake outlet. 



The most widely used sampling gear through- 

 out the system was tow nets, which was used in 

 open-water limnetic, areas, primarily to sample 

 juvenile sockeye salmon. Otter trawls, gill nets, 

 and seines, which were more effective than tow 

 nets in sampling pygmy whitefish, were used to 

 different degrees in different areas (table 1) . The 

 unknown vulnerability of pygmy whitefish to dif- 

 ferent types of gear and the unequal use of each 

 type in various lakes and basins should be kept 

 in mind when considering relative abundance. 



On the basis of the number of specimens ob- 

 tained in other geographic areas by previous col- 

 lectors, populations of pygmy whitefish may oc- 

 cupy a more dominant role in the overall fish 

 population structure in parts of the Naknek sys- 

 tem than in other areas. In the Lake Superior 

 study, the greatest single collection of pygmy 



PYGMY WHITEFISH OF SOUTHWEST ALASKA 



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