Changes in the life history of red porgy, Pagrus pagrus, from the southeastern United States, 1972-1994
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Author
Harris, Patrick J.
McGovern, John C.
Subject
Red porgyDescription
Aspects of the life history of red porgy from the South Atlantic Bight (SAB) were examined for four periods (1972-74, 1979-81, 1988-90, and 1991-94), and annual changes in the age and growth of red porgy were described for data collected during 1988-94. The life history of red porgy during 1972-74 was assumed to represent that of an unfished population. although this population had been subject to light fishing pressure. From 1972-74 to 1979-81, the back-calculated size-at-age increased slightly for ages 2-8. By 1988-90 and 1991-94. however, the back-calculated size-at-age for the same age classes was significantly smaller than that in 1979-81. In addition, size-at-maturity and size-at-sexual-transition occurred at progressively smaller sizes for 1988-90 and 1991-94. The mean size-at-age (observed and back-calculated) declined for most ages between 1988 and 1994. Von Bertalanffy growth curves fitted to the mean back-calculated size-at-age for each year showed similar decreasing trends. Changes in life history may be a response to sustained 20-year overexploitation that has selectively removed individuals predisposed towards rapid growth and larger size.Collections
Date
1997Metadata
Show full item recordDate Accessioned | 2013-08-22T14:12:51Z |
Date Available | 2013-08-22T14:12:51Z |
dc.description | Aspects of the life history of red porgy from the South Atlantic Bight (SAB) were examined for four periods (1972-74, 1979-81, 1988-90, and 1991-94), and annual changes in the age and growth of red porgy were described for data collected during 1988-94. The life history of red porgy during 1972-74 was assumed to represent that of an unfished population. although this population had been subject to light fishing pressure. From 1972-74 to 1979-81, the back-calculated size-at-age increased slightly for ages 2-8. By 1988-90 and 1991-94. however, the back-calculated size-at-age for the same age classes was significantly smaller than that in 1979-81. In addition, size-at-maturity and size-at-sexual-transition occurred at progressively smaller sizes for 1988-90 and 1991-94. The mean size-at-age (observed and back-calculated) declined for most ages between 1988 and 1994. Von Bertalanffy growth curves fitted to the mean back-calculated size-at-age for each year showed similar decreasing trends. Changes in life history may be a response to sustained 20-year overexploitation that has selectively removed individuals predisposed towards rapid growth and larger size. |
Media Type | Document |
Item Language | English |
Publisher | South Carolina State Library |
Digital Collection | South Carolina State Documents Depository |
Rights | Copyright status undetermined. For more information contact, South Carolina State Library, 1500 Senate Street, Columbia, South Carolina 29201. |
Type | Text |
Digitization Specifications | This South Carolina State Document was either saved from a document available publicly online in PDF format or converted to PDF using Adobe Acrobat X Professional. |