Gulf of Mexico commercial shrimp populations-trends and characteristics, 1956-59.

Date

1962

Authors

Kutkuhn, J.H.

Journal Title

Journal ISSN

Volume Title

Publisher

Abstract

Those phases of Gulf of Mexico fisheries concerned with the catching, landing, and initial processing of commercial shrimps are briefly described. Knowlege of each species' distribution and habits, manner of capture, handling, etc., is reviewed in an attempt to ensure proper interpretation of production statistics which are employed to draw inferences about commercial brown, pink and white shrimp populations. Methods of collecting, projecting, and compiling fishery statistics are critically examined to ascertain the relative accuracy and hence the usefulness of the statistics themselves. Real or potential biases acknowledged, available statistics for each species are used(1) to derive population density indices and (2) to delineate and trace population spawning classes. Short-and long-term trends in population strength are examined in light of trends in corresponding yield. Untoward fluctuations in yield are explained, where possible, in terms of observed population characteristics and their apparent relation to changes in environmental and intensity of exploitation. Although annual shrimp yields on a Gulfwide basis varied mildly, those of some species and in certain areas often fluctuated sharply, with fishing success in 1957 having been particularly poor. On the average, the brown shrimp proved to be the most important species, contributing roughly 56 percent by weight to total annual landings. Pink and white shrimp followed in that order, making up 22 and 20 percent, respectively. Centers of density in Gulf of Mexico brown, pink and white shrimp stocks ocurred respectively, off the coasts of Texas, southwest Florida and Yucatan, and Louisiana. Corresponding 4 year population trends were up moderately for the brown shrimp but down perceptibly for both the pink and white shrimp. Too intense harvesting of small shrimp immediately after recruitment is postulated as the cause of attribution in the Sanibel-Tortugas (southwest Florida) pink shrimp fishery. The sharp 1957 decline in the Louisiana white shrimp fishery is largely attributed to factors associated with intense storm systems which are believed to have compounded expected natural mortality during inshore phases of that year's early-season spawning class. Too heavy fishing on the dominant early-season spawning class generated the following year postponed initiation of a recovery trend.

Description

p. 343-402.

Keywords

shrimp, shrimp fisheries, catch statistics, fisheries, brown shrimp, pink shrimp, white shrimp, Penaeus aztecus, Penaeus setiferus, spawning, harvesting

Citation