Effects of fishing on population structure and life history of roman Chrysoblephus laticeps (Sparidae)

Abstract

The effects of fishing on the population structure and life history of roman Chrysoblephus laticeps, a protogynous hermaphroditic seabream from South Africa, were investigated by comparing fish from protected and exploited areas. Experimental (controlled) fishing and underwater visual census were used to sample roman and to measure population parameters inside and outside the Goukamma Marine Protected Area. Sites chosen for comparisons were adjacent and physically similar to reduce environmental influences on the comparison. Both methods revealed that roman had a higher density and mean size inside the protected area than outside. Age-at-maturity and ageat-sex-change were lower in the exploited area. The shift in age-at-sex-change maintained a constant sex ratio between the exploited and unexploited areas. The condition factor of roman from the protected area was lower than that of roman from the exploited area.