72 FISHERY INDUSTRIES OF THE UNITED STATES. 
only 56.18 ia cent of the 1908 catch and 24.38 per cent of the 1902 
catch; of clams, to only 27.14 per cent of the 1908 catch and 16.81 
per cent of the 1902 catch; and of oysters, to only 26.70 per cent of 
the 1908 catch and 21.21 per cent of the 1902 catch. 
The principal factors affecting the abundance of shad in our 
Atlantic coast waters appear to be unsatisfactory spawning areas, 
due to pollution and artificial barriers restricting the movements of 
the fish in the rivers, and interference with the fish in their migra- 
tions to the spawning areas and while on these areas. It is con- 
ceivable that, unless these conditions are rectified, the consumer 
may have to depend on the Pacific coast for these fish at some not 
far distant date. In North Carolina, while pollution is believed to 
have been a less signifieant factor than in some of the other States, 
interference with the free movement of a sufficient body of the fish 
to the spawning areas and during the spawning period is considered 
io be an important factor affecting the supply of fish in the waters, 
which fish-cultural operations have been unable to wholly counter- 
act. A study of the production figures for striped bass would indi- 
cate that the supply of this fish is being depleted. Difficulties in 
propagation, such as inability to procure ripe fish of both sexes at 
same time, handicap operations in this field. The decline in the 
catch of oysters would indicate how important it is for the State to 
give more serious consideration to the encouragement of oyster 
farming. In this connection the results of former mvestigations of 
the Bureau should prove of interest, notably a document by Dr. 
“aswell Grave.” 
FISHERIES BY COUNTIES. 
The statisties as to the number of persons employed, investment, 
and products of the fisheries of North Carolina in 1918 are given by 
counties in the appended table. It will be noted that of the catch 
of sea bass of 111,650 pounds, valued at $10,928, 59,650 pounds, 
valued at $5,763, are credited to Carteret County. The increase in 
the catch for this county is directly attributable in large part to the 
Bureau for its work in locating the small fishing grounds along this 
section of the coast and for encouragement given to the establish- 
ment of an important fishery. Difficulties in marketing the catch 
at satisfactory prices are reported to have retarded the fullest de-— 
velopment of this fishery. 
As a result of the Bureau’s efforts to develop fisheries for sharks 
and other unutilized aquatic animals and to encourage the saving 
of the hides for tanning into leather and the extraction of the liver 
oil of sharks, etc., 20,175 pounds of the hides of sharks, porpoise, 
etc., valued at $3,025, and 720 gallons of shark oil, valued at $540, 
were saved in 1918. 
10 Grave, Caswell: Investigations for the Promotion of the Oyster Industry of North America. Report 
U. 8. Commission of Fish and Fisheries, 1903 (1905), p. 247-341, X pl. 
