Age and growth and a preliminary stock assessment of stonebream Neoscorpis lithophilus (Pisces

Scorpididae) along the KwaZulu-Natal coast, South Africa

Bruce Q. Mann, Sean T. Fennessy, Anesh Govender, Bryan A. Van der Walt

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

The age and growth of the endemic scorpidid Neoscorpis lithophilus was investigated by use of whole otoliths from specimens collected along the KwaZulu-Natal coast, South Africa. Comparison between counts of growth increments from whole and sectioned otoliths showed no significant difference. Marginal increment analysis and oxytetracyline labelling were used in an attempt to validate the annual periodicity of growth increment deposition. A von Bertalanffy growth function gave an acceptable fit to the length-at-age data and the parameters L = 413.4 mm fork length, K = 0.222 year-1 and t0 = -0.981 described the growth of N. lithophilus for both sexes combined. The study revealed that N. lithophilus is a reasonably fast-growing species reaching an age of at least 10 years. Total fishing mortality rate (Z = 0.44 year-1) was estimated from the slope of the descending limb of a catch curve, natural mortality (M = 0.29 year-1) was estimated by empirical methods and fishing mortality (F = 0.15 year-1) by subtraction. Yield and spawning biomass per-recruit modelling revealed that the stock of N. lithophilus off KwaZulu-Natal is not overexploited.

Original languageEnglish
Pages (from-to)131-138
Number of pages8
JournalMarine and Freshwater Research
Volume53
Issue number2
DOIs
Publication statusPublished - 2002

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stock assessment
Pisces
South Africa
otoliths
coasts
coast
fishing mortality
otolith
limbs (animal)
periodicity
mortality
spawning
gender
biomass
limb
Africa
modeling
methodology

ASJC Scopus subject areas

  • Aquatic Science
  • Oceanography

Cite this

Age and growth and a preliminary stock assessment of stonebream Neoscorpis lithophilus (Pisces : Scorpididae) along the KwaZulu-Natal coast, South Africa. / Mann, Bruce Q.; Fennessy, Sean T.; Govender, Anesh; Van der Walt, Bryan A.

In: Marine and Freshwater Research, Vol. 53, No. 2, 2002, p. 131-138.

Research output: Contribution to journalArticle

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