AGE AND GROWTH OF Papyrocranus afer (GUNTHER 1868), AN EMERGING ORNAMENTAL FISH IN NIGERIA | UTTAR PRADESH JOURNAL OF ZOOLOGY
Papyrocranus afer are under threat from increased wild collection for aquaria, particularly juveniles. P. afer Lagoon age, growth, and growth derived metrics based on Length Frequency Distribution (LFD) study and interpretation of annual growth markers hard structures (namely scales, otoliths, opercula and cleithra). From January 2010 to December 2011, 1,154 individuals of P. afer were sampled monthly from Lekki Lagoon. LFD average lengths-at-age were 13.45 cm (Age 0+), 34.45 cm (Age 1+), 49.50 cm (Age 2+), and 61cm (Age 3+). To model the observed length-at-age data, the von Bertalanffy growth function was used: Lt = 77.6 (1 – e-0.33(t +0.46)). Lm (length at initial maturity) was 41.1cm, while Lopt (length at optimal yield) was 49.5cm. The presence of juvenile fishes (38 cm) in the catch indicates increasing overfishing. Annual growth markings on hard parts revealed ages 1, 2, and 3 years; mean lengths at these ages were 33.1, 44.6, and 58.4cm (cleithra), 29.1, 40.0, and 60.4cm (scale), and 29.1, 40.0, and 60.4cm (scale) (operculum). There are no interpretable growing signs on the otoliths. Overfishing highlights Papyrocranus' vulnerability to over-exploitation, highlighting the necessity for its conservation in Lekki Lagoon. Please see the link :- http://mbimph.com/index.php/UPJOZ/article/view/2892