Included are a brief description of menhaden purse-seine fishing gear, methods, and seasons; a summary of the major features of the 1955 Atlantic Coast purse-seine fishery; a description and analysis of the methods of sampling the catches; and tabular data resulting from the catch-sampling program. Measurements of the catch of Atlantic menhaden (Brevoortia tyrannus), apparent abundance, and total fishing effort showed considerable variation in different areas of the coast in 1955, with highest apparent abundance encountered on the North Carolina fall fishing grounds. Age, length, and weight composition of samples from the catches from 1952 through 1955 revealed the presences of a dominant year class in the fishery and established that different age and size groups support the catches in different areas along the coast; in summer, younger, smaller fish were found to occur in southern waters, and older, larger fish, farther northward. All age and size groupings were shown to be represented in the fall fishery off North Carolina.

The 1956 catch of Atlantic menhaden (Breyoortia tyrannus) amounted to 766,000 tons. Apparent abundance, as measured by catch per purse-seine set, was highest in the North Atlantic Area and lowest in Chesapeake Bay. Geographical distribution of fishing effort is shown. Samples for age, size, and sex determinations were obtained from the purse-seine and pound-net catches landed from Fernandina Beach, Florida, to Portland, Maine. Age composition showed that the 1955 years class (age-1 fish) accounted for more than half of the total catch. This year class dominated the summer catches in the South Atlantic and Chesapeake Bay Areas as well as the fall catches in North Carolina, while the 1954 year class (age-2 fish) dominated in the Middle Atlantic Area, and the 1951 year class (age-5 fish) dominated in the North Atlantic Area. Fish of the dominant year class in each of these areas were smaller in 1956 than in the previous year.