Biological parameters reflecting the current state of the exploited pink Dentex dentex gibbosus (Pisces: Sparidae) population off the canary islands

Abstract

A total of 639 pink dentex Dentex gibbosus was collected in Canary Islands waters between April 1991 and September 1993. Total lengths ranged from 14,2 to 95,2 cm. Females dominated smaller size-classes and males the larger ones. The species was characterized by protogynous hermaphroditism. The overall ratio of males to females was 1 : 1,45. The reproductive period extended from April to September, spawning peaking in June/July. The total lengths at 50% maturity were 34,7 cm for females and 38,6 cm for males. The length-mass relationship for the whole sample can be described by the parameters a = 0,01014 and b = 3,0812. Fish aged 0–16 years were present in the samples. The parameters of the Von Bertalanffy growth equation were: L ∞ = 101,2 cm, k = 0,149·year−1, and t 0 = −0,111 years. The rates of total mortality Z and natural mortality M were 0,57 and 0,28·year−1 respectively. Rates of fishing mortality F and exploitation E were 0,29 and 0,51·year−1 respectively. The estimated length at first capture (LC 50) was 17,8 cm total length.