Age, growth and retrospective stock assessment of an economically extinct sparid fish, Polysteganus undulosus, from South Africa

Age and growth of the estuarine-dependent sparidAcanthopagrus berdain northern KwaZulu-Natal, South Africa

“…In this study, marginal increment analysis and oxytetracycline labelling were used to validate age estimates, and showed strong evidence that one opaque increment is deposited annually. These results are consistent with results from other South African sparid species, which have also been shown to deposit one opaque increment annually (Coetzee & Baird 1981;Buxton & Clarke 1986;1989;Buxton 1993, van der Walt & Beckley 1997Chale-Matsau et al 2001).…”

“…This was not the case in this study. Stacking of growth increments in older fish, which reduces readability and is often apparent in the otoliths of many other sparid species (Smale & Punt 1991;Buxton & Clarke 1992;Bennett 1993;Mann & Buxton 1997;Chale-Matsau et al 2001), was not found to be a problem in A. berda.…”

Age and growth of Argyrozona argyrozona (Pisces: Sparidae) in a marine protected area: an evaluation of methods based on whole otoliths, sectioned otoliths and mark-recapture

“…APE ranged from 3.9 in Sarpa salpa (Van der Walt and Beckley, 1997) to 4.7 in Rhabdosargus sarba (Radebe et al, 2002), both of which are short-lived species, reaching 6 and 16 years, respectively. While another long-lived species Polysteganus undulosus showed poor precision with an APE of 18.23 (Chale-Matsau et al, 2001). While marginally higher than that for short-lived sparids the APE for carpenter in the TNP (5.3) was substantially lower than that of P. undulosus.…”

An Assessment of the Recreational and Commercial Skiboat Fishery in the Transkei

“…slinger (Punt et al 1993), dageraad (Buxton 1992), seventyfour (Chale-Matsau et al 2001), red steenbras (Penney and Wilke 1993), Scotsman (Garratt et al 1994), poenskop (Buxton and Clarke 1989), kob (Griffiths 1997a, b) and geelbek (Griffiths 2000b). Combined with the poor compliance and minimal enforcement of regulations in the area, the long-term prognosis for the skiboat fishery is not good.…”