FISHERY BULLETIN: VOL. 69, NO. 4 



except for the year 1937, when the maximum 

 size was reduced to 100 fm for 1 year and only 

 for Nushagak Bay. 



Powered fishing boats were outlawed in 1922 

 and not permitted again until 1951. However, 

 in the 30's the canning companies started to use 

 small tug boats to tow the fish boats fi'om one 

 place to another, or most commonly to assist in 

 bringing a boat to the delivery scow. Conse- 

 quently, the efficiency of one boat increased with 

 this added mobility. In part, it was offset by 

 the movement of fishing boundaries over the 

 years farther and farther out from the river 

 mouth and thereby reduction in efficiency of the 

 fishing gear. 



In 1899, fishing above tidewater was prohib- 

 ited in streams less than 500 ft in width. In 

 the tidewater of smaller streams, gear could only 

 cover one-third of the stream width. 



In 1907, fishing in the Wood and Nushagak 

 Rivers was prohibited within 500 yards of the 

 mouth of Wood River. Over the years, gradu- 

 ally, restrictions of fishing area have been im- 

 posed, which resulted in a transfer of fishing 

 operations away from the river and river mouth 

 and into the open Nushagak Bay. In Figure 3 

 are indicated locations of canneries in operation 

 shortly after the turn of the century. Only three 

 plants remain actively canning in Nushagak Bay 

 today. 



THE NATURE OF THE SOCKEYE 

 SALMON RUNS 



All sockeye salmon runs to Bristol Bay have 

 a very distinct and regular time schedule. His- 

 torically, the period from June 25 to July 25 

 has been considered as the time when the salmon 

 are present in Nushagak Bay in catchable quan- 

 tities. Records accumulated since 1955 indicate 

 that, on the average, peak catches in Nushagak 

 Bay were made on July 5 (Royce, 1965). 



The entry is of a i)ulse tyjie with exponential 

 declining departure curves for the trunk streams 

 and the spawning grounds (Mathisen, 1969). 

 Bi- or trimodal catch curves, especially in earlier 

 years, undoubtedly were created by changes in 

 frequency or I'ehilivc strength of the individual 

 pulses. We do not know the racial composition 



NUSHAGAK RIVER DISTRICT 



Figure 3.— Copy of an old map (probable date 1907) 

 with the locations of canneries and salteries in Nushagak 

 Bay. Canneries in operation today are the Columbia- 

 Wards Cannery at the site of North Alaska Salmon 

 Company Cannery, a Queen Fisheries plant near Co- 

 lumbia River Packers Association plant, and Pacific 

 Alaska Fisheries Dillingham plant at the site of Alaska- 

 Portland Packers Association. 



of the individual pulses, but some tagging data 

 (Straty, 1969) jjoint to a fairly random mixing 

 of individual races. 



Basically, the juvenile salmon spend 1 or 2 

 years after emergence in the nursery areas of 

 the freshwater lakes. They return from ocean 

 feeding after 2 or 3 years. Thus, four different 

 age groups will make up a year's run, namely, 

 1.2, 1.3, 2.2, and 2.3 (after Koo's [1962] nota- 

 tion). The number of fish in other age groups 

 is insignificant and can be disregarded. The 

 Nushagak District differs from other districts 

 in Bristol Bay in having a preponderance of 1- 

 freshwater check salmon. 



ESCAPEMENT LEVELS IN THE 

 NUSHAGAK DISTRICT 



The history of the Nushagak fishery was di- 

 vided earlier into three periods. Within each 

 of these periods data exist in regard to escape- 



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