PROGRESS IN BIOLOGICAL INQUIRIES, 1938 Sl 
maintain them. Results indicate that a venture of this nature can be 
successful only through frequent personal contacts with the men 
keeping the logs. One shrimp cannery in Georgia kindly allowed 
the transcription of its entire boat catch records from 1921 to 1937. 
These records, which were copied in 1988, should be of considerable 
value in tracing the progress of the central Georgia shrimp fishery 
during its period of most rapid development. 
It is quite evident from the work done so far that if adult shrimp 
survive for 2 or more years in any quantities along the Atlantic coast, 
they must move into deeper offshore areas beyond the range of the 
present commercial fishery. This important information which is 
lacking in our knowledge of the life-history of the common shrimp 
can only be determined by thorough scouting of the offshore waters 
between Cape Hatteras and Cape Canaveral. Exact knowledge, 
which is not now available, of the depth distribution of the shrimp 
along the Atlantic coast during the spawning season is of particular 
importance in attempting to delimit the spawning areas. Tentative 
plans are being made for the use of the Pelican on the Atlantic coast 
after the completion of the Gulf survey. 
The expansion of the offshore fishery in the Gulf has raised the 
important question of whether these shrimp are of local origin or 
whether they are migrants from other States. It was deemed ad- 
visable, because of the urgent need for knowledge of the movements 
of shrimp in the Gulf, to suspend activities at the Brunswick (Ga.) 
station in the fall and transfer Zawnch 58 to New Orleans for tagging 
operations. The first of the Louisiana tagging experiments was in- 
augurated during December, when 2,300 shrimp were released 
between the Mississippi River and Ship Shoal. The objective of 
these experiments, which should be extended to cover the entire 
fishery, is to determine the migrations, growth, age, and fishing in- 
tensity of the Gulf shrimp. Tagging will be continued during the 
coming year as funds permit. 
ECOLOGICAL STUDIES 
The Texas Investigation is operated on a cooperative basis with 
the Coastal Division of the Texas Game, Fish and Oyster Commis- 
sion. With the transfer of Kenneth H. Mosher to the Pacific Pil- 
chard Investigations, the sampling of the commercial catch at 
Aransas Pass was discontinued. Albert Collier, of the Texas Com- 
mission, has conducted studies during the year to determine the rela- 
tionship between the environmental changes and the distribution of 
shrimp in Aransas Bay. What effects do temperature, salinity, tides, 
currents, and food have on the reactions of the shrimp in its natural 
habitat? What determines the time when young shrimp leave the 
shoaler nursery grounds for Aransas Bay and later for the Gulf? 
Why does the success of the commercial catch fluctuate so greatly 
from day to day? Can these fluctuations be determined in advance? 
Is there actually a definite distribution pattern of shrimp in Aransas 
Bay, as appears to be the case from the commercial catch, and if such 
a distribution is present what is the cause? These and many other 
problems require solution for a better understanding and wiser util- 
ization of the shrimp supply. 
