PROGRESS IN BIOLOGICAL INQUIRIES, 1938 25 
mereased from approximately 30 vessels in 1931 to over 125 vessels 
in 1988 and includes, in addition to local vessels, boats from New 
Jersey, New York, and Massachusetts. Landings are made mostly 
in Virginia and, to a lesser extent, in New Jersey and New York 
City. 
The economic importance of this winter trawl fishery has increased 
since its beginning in 1931 through the creation of new market out- 
lets for its production, particularly in the Southern States. This 
activity has also affected the distribution of numerous fishery prod- 
ucts and introduced keen market competition with other distributing 
and production points, particularly in the Middle Atlantic States. 
The activity of the winter trawl fishery is of biological significance 
in the probable effect it may have on the supply of those species 
that comprise its catch. To date there is no evidence that the winter 
fishery has caused any significant decline in the supply of scup. 
A reasonable doubt, however, exists as to whether the sea bass and 
fiuke can withstand successfully the combined withdrawal of: the 
winter and summer fisheries. Continued decreases in the catch per 
unit of effort for both species in most of the recent years and a similar 
reported decline in the summer fishery indicates a diminishing supply, 
probably from actual decreases in abundance. It is recognized that 
the winter trawl fishery may not be wholly responsible for this diminu- 
tion in the catch but that the activity of the sport and commercial 
summer fisheries may also be contributing to the reported decline. 
A detailed study of fluke and sea bass, based on observations of the 
summer and winter fisheries, is therefore recommended to determine 
the cause of this decline and what corrections for restoring higher 
levels of abundance are necessary. 
ANADROMOUS FISHES 
Striped bass.—In 1938 two important reports dealing with the life 
history and conservation needs of this species were submitted for 
publication. Dr. Vadim D. Vladykov submitted to the Maryland 
Conservation Department a report on his investigation in Chesapeake 
Bay in 1936 and 1937, and Dr. Daniel Merriman submitted to the 
Bureau his report on studies begun in 1936 under the auspices of the 
Connecticut Board of Fisheries and Game, and continued in 1937 
and 1938 with the cooperation of the Bureau and several Atlantic 
Coast States. 
The following are the principal results of these studies: The striped 
bass is subject to year-class dominance. When successful spawning 
occurs, as it did in 1934 in Chesapeake Bay, not only are local stocks 
greatly augmented, but, as a result of migration, abundance is greatly 
mereased along the coast from New Jersey to southern New England, 
and even in the Gulf of Maine. Since the large brood of 1934 was 
produced in a year when spawning adults were scarce, it is doubtful 
whether increased numbers of spawners should be the primary object 
of conservation measures. Catch records and studies of age com- 
position of the catch indicate that the numbers of such successful 
broods diminish rapidly. For example, the 1934 year class yielded 
only about one-fourth as many fish in 1937 as in 1936. Tagging ex- 
periments indicated that the fishery accounts for most of the decline. 
Protection of striped bass until they reach a length of at least 16 
