PROGRESS IN BIOLOGICAL INQUIRIES, 193 3 337 



At Beaufort, N.C, Dr. J, S. Outsell has continued his coUcctions 

 of youn<2; and adult shrimp. In addition, he is studyin<>- the histo- 

 logical development of ovarian ejrgs of the three species of shrimp in 

 an attempt to delimit more closely the spawnini^ times and places. 



During 1{>38 the South Atlantic work carried on by W. W. Ander- 

 son at Brunswick, Ga., was extended to cover the entire coast from 

 Charleston, S.C., to Cape Canaveral, Fla. This program was 

 initiated in May after an exploratory tri]) to the Cape Canaveral 

 grounds in January had indicated the possibility of extensive move- 

 ments of the shrimp along the South Atlantic coast during late 

 fall and winter. Nine stations were established along this 30b-mile 

 stretch of coast, as follows : Stono Inlet, S.C. ; Gaskins Bank, S.C. ; 

 St. Catherines Island and Brunswick, Ga. ; Fernandina, Mayport, 

 St. Augustine, New Smyrna, and Cape Canaveral, Fla. The stations 

 are distributed from 1 to 6 miles off the places mentioned. Each 

 locality was visited once every month and 2 or 3 hauls of 1 hour 

 each were made. In addition, the inside waters consisting of the 

 creeks, rivers, and sounds, in the vicinity of Brunswick, were trawled 

 for slirimp each month. 



Analysis of the data gathered at these stations indicates that there 

 are no important nursery grounds for the common shrimp south of 

 St. Augustine, Fla., while the reticulated coastal sections of Georgia 

 and northern Florida appear to be the major nursery area of the 

 South Atlantic. This observation tends to corroborate other 

 evidences wdiich imply that the postlarval shrimp that spawn in the 

 ocean or Gulf of Mexico and pass their larval stages there must reach 

 the inside w^aters at an early stage in order to survive. Additional 

 work is needed to substantiate this point definitely. 



Length frequency distributions of the common shrimp along the 

 Georgia coast during the fall and winter of 1931-32 and 1932-33 

 show a definite disappearance of the large shrimp (above 140 milli- 

 meters) from the fishery areas. During both years this disappear- 

 ance began with the onset of cold weather in October and reached 

 its maximum in January and February. Coincident with the dis- 

 appearance of the large shrimp from the Georgia grounds there 

 arose a fishery in the vicinity of Cape Canaveral, Fla. This Florida 

 fishery usually reached its maximum in January and rapidly de- 

 clined thereafter until by the latter part of March only a remnant 

 remained. The January (1933) trip to these southern grounds dis- 

 closed the fact that the shrimp population at Cape Canaveral was 

 comi)osed almost exclusively of large shrimp, for over 97 percent 

 were above 140 millimeters and 62 percent were between 156 and 

 370 millimeters. 



This evidence would indicate a southw^ard movement of the large 

 shrimp throughout the fall and winter w^ith a concentration neai" 

 Cape Canaveral. However, during the fall and w^inter of 1933, al- 

 though the scarcity of large shrimp was as evident along the Georgia 

 coast as in the previous two years, the Cape Canaveral fishery failed 

 to materialize to the extent it had during the previous tw'o winters. 

 This leads to four possible hypotheses: (1) The movement of shrimp 

 is not from north to south, but from inshore to offshore waters: (2) 

 the large shrimp at Georgia points were depleted during the sum- 

 mer and early fall fishery, consequently only a few remained to move 



