6 



BULLETIN OP THE BUREAU OF FISHERIES 



The aquatic vegetation of Karluk Lake is peculiar, in that the abrupt slope of 

 the bottom away from the shores provides little opportunity for the growth of the 

 larger aquatic plants. The small bay near Bear Point supports a dense growth of 

 Potamogetons, and there is a scattering growth near the foot of the lake, off the 

 mouth of Moraine Creek, and in the shallow channel between Camp Island and 

 Island Point. The rocks and bowlders alongshore, and to a considerable depth, 

 are covered with a dense growth of filamentous algae of several species, however. 

 The smaller lakes (Thumb and O'M alley) are much shallower, and m spite of their 

 small area each of them supports a much greater growth of the larger aquatic plants, 

 Potamogeton and Elodea, than does Karluk Lake proper. The shores of the lakes, 

 the valleys, flats, and the lower slopes of the surrounding hills are well covered with 

 groves of cottonwoods, alders, birches, and willows, and a variety of shrubs. By 

 midsummer the narrow flats along the lakes and in the valleys and the more gentle 

 slopes of the mountains are covered thickly with fireweed (Epilobium angustijolium) 

 and tall grass, which make travel exceedingly difficult. 



The climate of Kodiak Island is temperate. For 10 years the average tempera- 

 ture for the month of July (the warmest month) was 55.22° F., and for January 

 (the coldest month) 28.92° F. 2 Karluk Lake usually freezes over in winter. Accord- 

 ing to information secured from reliable natives, who frequent the lake during the 

 winter for hunting and trapping, it is usually frozen in by Christmas and opens 

 again some time in April. Occasionally, however, during a very mild winter, such 

 as was experienced in 1925-26, the lake does not freeze, but this is reported to happen 

 only about once in 20 or 25 years. The surface temperature of the lake in summer 

 is between 13° and 15.5° C. (55° to 60° F.). During the warm summer of 1926 the 

 temperature for several weeks in July and August was close to 15° C, and Chamber- 

 lain reports that early in September, 1903, the surface temperature was 44° F. 

 (6.7° C), but that it had "fallen about 10 degrees in as many days." This would 

 make the temperature at about August 23 of that year 54° F. (12.2° C), and no 

 doubt it had been higher earlier in the season. 



STATISTICAL HISTORY OF THE FISHERY 



Table 1 gives the yearly catch of red salmon at Karluk from the beginning of the 

 commercial fishery in 1882 up to and including the season of 1926. The data are 

 presented graphically in Figure 6. 



The catch of 1882 contained less than 60,000 red salmon, but this increased rapidly 

 until by 1888 the annual catch was greater than 2,000,000 fish. A high level of 

 productivity was maintained, with only occasional poor catches, for about 20 years. 

 During this period, from 1888 to 1907, the catch fell below 1,000,000 fish only once, 

 and the average yearly yield was 2,304,803 fish. Since 1907, however, the catch has 

 been appreciably less. In this period of 19 years there have been seven in which the 

 catch fell below 1,000,000 fish, and the average yield for the entire period was only 

 1,306,152. It is apparent from the graph, furthermore, that it is not only the average 

 yield that is reduced in the later years, but that both the maximum and the minimum 

 yields are getting smaller. In other words, the good years have been getting poor and 



1 Geological and Mineral Resources of Kenai Peninsula, Alaska. By G. C. Martin, B. L. Johnson, and U. S. Grant. Bul- 

 letin, vol. 587, United States Geological Survey, 1915. Washington. 



