Age and growth of the estuarine-dependent sparid Acanthopagrus berda in northern KwaZulu-Natal, South Africa

N.C. James, B.Q. Mann, L.E. Beckley, A. Govender

Abstract


Ages were estimated for the tropical sparid,

Acanthopagrus berda, caught in northern KwaZulu-Natal estuaries. Whole otoliths were used in the age determination. Age estimates were validated by marginal increment analysis and oxytetracycline labelling, which indicated that opaque deposition occurs primarily from September to November each year. The reproducibility of age estimates was described by a coefficient of variation of 10%. The von Bertalanffy growth curve was found to best describe the growth of A. berda. The parameters of the von Bertalanffy growth curve indicated that A. berda

in northern KwaZulu-Natal is a slowgrowing species, capable of reaching at least 16 years of age. Longevity of the species, coupled with sex change, late maturation and estuarine dependency, give cause for concern for the continued sustainable utilization of this species.


Keywords


whole otoliths, von Bertalanffy growth curve, slow growing, long-lived.

Full Text:

PDF

Refbacks

  • There are currently no refbacks.

Comments on this article

  • Ijhar
    "Ijhar" (2012-06-13)
View all comments





ISSN 2224-073X (online) ; ISSN 1562-7020 (print)

Powered by OJS and hosted by Stellenbosch University Library and Information Service since 2011.



Disclaimer:

This journal is hosted by the SU LIS on request of the journal owner/editor. The SU LIS takes no responsibility for the content published within this journal, and disclaim all liability arising out of the use of or inability to use the information contained herein. We assume no responsibility, and shall not be liable for any breaches of agreement with other publishers/hosts.

SUNJournals Help