BUREAU OF FISHERIES SA | 
move from the waters of one State to those of another, so that effec- 
tive conservation of the supply must be accomplished by unified 
action of the States concerned. Clear evidence of interstate migra- 
tions was obtained in waters east of the Mississippi. 
Surveys on the South Atlantic coast during the spring months of 
1940 revealed a critical condition which threatened the production of 
a crop for next year’s fishery. The number of spawners had been re- 
duced to a dangerously low level through the operation of two fac- 
tors: The excessive winter fishery in Georgia and Florida which draws 
upon virtually the entire South Atlantic population of large, migra- 
tory shrimp, and the unusually cold winter which killed large numbers 
of the small shrimp which do not migrate but remain in coastal waters 
as far north as North Carolina. Because of this drastic reduction 
of the stock, the cessation of all fishing until July 1 was recommended 
in order that the remaining shrimp might have an opportunity to 
spawn. 
North Pacific and Alaska fishery investigations—F¥or the second 
consecutive year the activities of the Columbia River staff have been 
concentrated upon the problem of salvaging the portion of the salmon 
run which is barred from its accustomed spawning grounds by the 
erection of the Grand Coulee Dam. Salmon, steelhead trout, and 
other fishes bound for the upper Columbia River are being trapped 
as they pass through the fish ladders at Rock Island Dam, 150 miles 
downstream, and transferred to tributaries of the Middle Columbia 
where suitable conditions exist and where it is desired to build up 
the runs. Because the chinook and blueback salmon have a strong 
instinct to return to the streams in which they have spent the early 
months of life, it is expected that such trapping operations will be 
necessary only throughout one complete cycle of salmon runs. Dur- 
ing the period from May 1 to December 9, 1939, 41,722 fish were 
hauled, of which 36,224 were salmon and steelhead trout. The loss 
of fish during trapping and hauling was extremely small and ob- 
servations later in the season revealed successful spawning. 
In the Puget Sound area, where the coho salmon are important 
both from the standpoint of food and recreation, returns of these 
fish from marking experiments conducted in previous years indicate 
that releasing fingerlings in the fall produces slightly larger returns 
and is less expensive than releasing them in midwinter, and is greatly 
to be preferred to releasing them in the spring of their second year. 
Observations on the salmon populations of Bristol Bay, for the 
purpose of collecting data on which to base a program of manage- 
ment for this valuable resource, were made in 1939 for the second 
consecutive season. The study of the life histories of the races of 
salmon populating the lakes and rivers in a watershed of over 
