A preliminary assessment and management of gilthead bream Sparus aurata in the port Said fishery, the southeastern mediterranean, Egypt

A total of 1714 gilthead bream Sparus aurata was collected from the Port Said fishery between January 2004 and February 2005. Total length ranged from 10 to 35.5 cm while total weight varied from 18 to 650 g. The length-weight relationship parameters were a = 0.0123 and b = 3.0284. The age distribution covered age groups 0 to IV. The parameters of the von Bertalanffy growth function in length were K = 0.5 year-1, L∞ = 37.98 cm and t0 = -0.6 years. The rates of total (Z) and natural mortality (M) were 1.95 and 0.62 year-1, respectively. The fishing mortality (F) was 1.33 year-1 and exploitation rate (E) of 0.68 indicated that the population has been heavily exploited. The estimated total length at first capture (Lc) was 11.1 cm, while the total length at 50% maturity (Lm) was 25.77 cm. The reproductive activity of gilthead bream in the Port Said fishery took place between November and February, with the greatest intensity in December. Yield per recruit analysis revealed over-fished stock conditions particularly due to small fish being effectively unprotected by the current minimum size regulations.

Anahtar Kelimeler:

Akdeniz, Mısır (ülke), populasyon dinamiği, balıkçılık, Pagrus aurata, yumurta bırakmak, izmaritgiller

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