32 U. S. BUREAU OF FISHERIES 
and Alabama, during 1939, have shown that the shrimp populations 
in these three States move from one State to another. Here, again, we 
have the necessity for two or more States to unite in their efforts to 
properly regulate a migratory fishery. 
Inasmuch as the common shrimp does not possess any of those 
structures common to many fishes and molluses by means of which 
the age of an individual specimen can be determined; and inasmuch 
as the shri imp apparently has a relatively short life span, an extended 
spawning season, a complex migratory nature, and the habitat changes 
markedly during its life span, many problems concerning its life and 
habits can be solved only by means of tagging. The problem of growth 
is complicated at certain periods of the year by local movements, 
migrations, an extended spawning season, and the lack of dominant 
size classes. The problem of fishing intensity has presented innumer- 
able difficulties due to the lack of adequate ‘atch statistics in all of the 
shrimp- producing States. This problem has been complicated fur- 
ther by the migratory nature of the shrimp and the fishing boats. 
Tagging experiments are the most feasible approach, so far devised, 
to the pr oblems of growth, migration, longevity, and fishing intensity. 
Tagging constitutes a technique that has proven successful in tracing 
migrations of the South Atlantic shrimp and in providing information 
on the other questions. All of these problems require solution before 
a well-founded management of the fishery can be proposed. 
Because of extensive offshore fishing and the migratory nature of 
the shrimp, tagging experiments were first conducted along the At- 
lantic coast. Now, however, with the establishment of an offshore 
fishery in the Ship and Trinity Shoals area off central Louisiana, 
a means is provided for securing the return of tags throughout the 
year. During the last few w eeks of 1938 the eround work was laid 
for a series of shrimp-tageing experiments in Louisiana waters. 
Fishermen and dealers through rout the experimental area first were 
made acquainted with the nature of the investigations to be per- 
formed, by means of newspaper articles, talks, and posters. The 
willing assistance and genuine interest of the industry have con- 
tributed to the success of the entire program. The fishermen co- 
operated by returning captured tagged shrimp and reporting where 
and when they were “taken, and the dealers preserved and retained 
the specimens and data on their premises until the Bureau’s agent 
could collect them. 
The tagging program commenced during mid-December of 1938, 
when 2,300 shrimp were released in 3 localities between the Missis- 
sipp1 and the Atchafalaya Rivers. During the following month 
1,750 additional tagged shrimp were released in the Ship Shoal 
area. Although these initial plants of approximately 4,000 shrimp 
were to have “been succeeded by regular monthly releases, an un- 
foreseen shortage of funds forced the temporary cessation of the 
work until the following summer. Tagging was resumed in late 
August 1939 and continued uninterruptedly for the remainder of 
the: year, and 12,200 shrimp were released during the period. At the 
same time the area of operations was extended to include inland 
bays and lakes, as well as offshore waters, and releases were made 
in Alabama and Mississippi in addition to Louisiana. 
Field work has been so extensive that very little time has been 
available for analysis of the data gathered. Preliminary observa- 
