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Summary The age and growth of three goatfish species Mulloidichthys flavolineatus (Lacepède, 1801), Mulloidichthys vanicolensis (Valenciennes, 1831) and Parupeneus forsskali (Fourmanoir & Guézé, 1976) from Egyptian Red Sea, Hurghada region were studied based on otolith readings. The fishing operated mainly by gill and tramml nets with mesh sizes renging from 0.5 to 3 cm. The maximum longevity of the three species was found to be 6, 5 and 5 years for M. flavolineatus, M. vanicolensis and P. forsskali respectively. The age I was the dominant age group forming 50.18% for M. flavolineatus and 46.13% for P. forsskali. While age group II was most frequent in M. vanicolensis (50.67%). The asymptotic length (L∞) and the growth rate (K) were estimated with 38, 33.3 and 31.6 cm as well as with 0.27, 0.37 and 0.32 per year for M. flavolineatus, M. vanicolensis and P. forsskali, respectively.

Rabbitfishes, family Siganidae, are one of the most abundant fishes inhabiting the Red Sea and now widely distributed in the Mediterranean. Age and growth of Siganus rivulatus, the most common species, were studied from samples collected randomly between October 2017 and October 2018 from Shalatein landing site. Otoliths of 2000 specimens were used for age determination and the maximum attained age for this species was four years. The von Bertalanffy growth parameters L ∞ , K and t o and the instantaneous annual rates of total, natural and fishing mortality were estimated and consequently the exploitation rate was determined. It is found that the current exploitation level is higher than the optimum one reflecting the intensive exploitation of S. rivulatus in the Southern Red Sea, Egypt. Yield per recruit analysis revealed that fishing effort should be decreased. This can be adopted through closed seasons/areas, increase of mesh size, increase of minimum landing size and setting of a total allowable catch (TAC).

The age and growth of two grouper fish species, Epinephelus summana (Forsskål, 1775) and Cephalopholis argus (Schneider, 1801) from Egyptian Red Sea off Hurghada, were studied based on the otolith readings. The maximum longevity of the two species was 10 and 6 years for E. summana and C. argus respectively. The age group II was the most dominant age group in the catch forming 46.09 % for E. summana and 22.33% for C. argus from the total collected samples. The asymptotic standard length (L∞) and the growth coefficient (K) were estimated as 63.39 cm and 0.13 year -1 for E. summana and 44.22 cm; and 0.26 year -1 and C. argus, respectively. The total mortality was computed as 0.82 and 1.31 year -1 for E. summana and C. argus, respectively. The mean values of natural mortality were 0.33 and 0.56 year -1 for E. summana and C. argus, respectively. Accordingly, the fishing mortality rates were estimated as 0.49 and 0.75 year -1 for E. summana and C. argus, respectively. The exploitation rates of E. summana (0.6) and C. argus (0.57) along with the fishing mortality rates reflect the overexploitation situation of the two serranid species in the Egyptian Red Sea.

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