Population biology of sparid fishes in Qatari waters 2. Age, growth and mortality of black-banded bream, Mylio bifasciatus (forsskal)

Abstract

Age, growth and mortality of black-banded bream (faskar) Mylio bifasciatus from the Arabian Gulf waters off Qatar were estimated. The study was conducted on 314 fish obtained from the trawl catch of Qatar National Fishing Company during January 1992 -May, 1993. The study revealed that the maximum age of fish sampled was 14 years. The length / scale relationship was TL = 3.596 + 0.1465 TS. The relationship between total length and total weight was best fit by the following curvilinear equation: TW = 0.01727 TL3.01621 -j^g yon Bertalenffy growth equation was Lt = 47.12 (l-e"°-14 (t+l-69)) The back-calculated data indicated that the growth in length of faskar was highest at the end of the first year of life, followed by a gradual, continuous decrease throughout the fish life. The growth in weight showed an irregular pattern with an annual increment ranging from 77-167%. The total mortality estimate (Z), calculated from the catch curve was 0.398/year, while the survival rate(S) was 0.67, indicating that 67% of faskar survive per year after the third year of life.

لقد اجريت هذه السراسة لتقدير العمو ومعدلات النمو والنفوقى في سمك الفسكر في المياه القطرية خكل الفترة من يناير 1992 إلى مايو 1993 م . وقد أوضحت نتائج الدراسلة أن أقصى عمر يمكن ان تصك إليه هذه الأسماك هو 14 سنة ، وكانت العلاقة بين الطول الكلي للأسماك وقطر قشورها علاقة خط مستقيم ممثلة بالمعادلة الآتية : الطول الكلي = 3.596 + 0.1465 x طول قطر القشرة ، .