Age, growth and food of Cheimerius nufar (Ehrenberg, 1820) (Sparidae), collected off St Croix Island, Algoa Bay

Abstract

Age and growth of the santer, Cheimerius nufar, were determined from otoliths. One hyaline and one opaque ring are laid down yearly. The von Bertalanffy growth function yielded the equation L t = 953,56 [1-e-O,0654(t+2,6177~. The length-mass relationship W = 0,00005 L 2,7831 was used to determine growth in mass: W t = 9790,24 [1_e-O,0654(t+2,617~2,7831. Stomach and intestine content analyses were done, using a modification of the points method, as well a~ the frequency of occurrence method. C. nufar is primarily a piscivore, but also preys on cephalopods and crustaceans. S. Afr. J. Zool. 1981, 16: 137-143 Die ouderdom en groei van die santer, Cheimerius nufar, is bepaal met behulp van otoliete. Een hialien-en een opaakring word jaarliks gevorm. Die von Bertalanffy-groeifunksie word beskryf deur die vergelyking L t = 953,56 [1_e-O,0654(t+2.617~. Deur gebruik te maak van die lengte-massa verwantskap W = 0,00005 L 2,7831 kan groei in terme van mass a uitgedruk word as: W t = 9790,24 [1-e-O,0654(t+2,6177~2,7831. Maag-en derminhoude is ondersoek en gekwantifiseer met behulp van 'n metode van gemodifiseerde punte, asook die metode van frekwensie van aanwesigheid. C. nufar is primer visvretend, maar voed ook op koppotige diere en skaaldiere. In the past most teleost research in South Africa has been directed towards commercially exploited fish stocks. More recently attention has been called to angling fish stocks and the importance of sport fishery (Van der Elst 1976a, b; Anon. 1979). Few studies however have been made of the biology of angling fish species in South Africa. The Sparidae constitute a large proportion of the angling fish species, and the general biological work done (taxonomic research excluded) is that of Gilchrist (1903.