STATISTICAL SURVEY PROCEDURE 



383 



Fish Sticks and Port lo n s --Quarterly Information is collected and published on the pro- 

 duction and value of breaded, cooked and raw fish sticks, breaded, cooked and raw fish portions, 

 and unbreaded fish portions . The data are released in the Service' s Current Fishery Statistics series 

 of bulletins . 



Cold-Storaqe Holdings of Fish — Information on the monthly freezings and holdings 

 of fishery products is obtained from cold storage warehouses by mail and by NMFS employees. 

 Data are also obtained on the holdings of certain cured fish. Bulletins showing these statistics 

 are issued monthly and annually. 



Detailed cold-storage statistics also are published in the Statistical Digest. Information 

 regarding cold-storage holdings of fishery products has been published since 1917, while data on 

 the quantity of fish frozen have been released for the years from 1920 to 1925, inclusive, and 

 continuously since 1928. 



Foreign Fishery Tr a de - -Statistics on foreign trade are obtained from compilations 

 made by the Bureau of the Census, Department of Commerce. Statistics on all known imported or 

 exported fishery products have been assembled and published annually since 1926 in the Digest. 

 For earlier years, figures are available in the reports of the Bureau of the Census, Bureau of For- 

 eign and Domestic Commerce, the Bureau of Statistics, the Department of Commerce and Labor, 

 or the Treasury Department. 



PRACTICES AND TERMS 



Certain practices and terms used in this report are explained below. 



Operating U n i t s - -Operating units include persons employed in the fisheries, and craft 

 and gear engaged in the fisheries. 



Vessel - -A craft having a capacity of 5 net tons or over. 



Boat — A craft having a capacity of less than 5 net tons. 



Days Ab se nt - -In computing "days absent" for vessels landing fares at certain Massa- 

 chusetts ports, the day of arrival, but not the day of departure, is included; thus, a vessel leav- 

 ing port on the 8th of the month and returning on the 15th of the month will be credited with 7 

 days'absence . Prior to 1944, "days absent" Included both the day of departure and the day of 

 arrival . 



Days Fished — In computing "days fished" for fishing craft landing shrimp at Gulf of Mex- 

 ico ports, the total number of hours spent in fishing effort has been divided by 24. 



Fish — Tiie term "fish" as used in this report includes all species belonging to the class 

 Pisces . 



Shell fish et al . — A shellfish is an aquatic invertebrate animal having a shell, such as 

 a mollusk or crustacean. However, in order to reduce the classifications appearing in the catch 

 tables, all items not properly listed as "Fish" or "Whale Products" have been included under 

 "Shellfish etal." Accordingly, turtles , frogs , sponges , seaweed, and worms are included under 

 this classification. 



