( BIOLOGY AND GONADAL CYCLIC CHANGES IN FISHES OF FAMILY MUGILIDAE IN CLOSED FRESH WATER ( NOZHA HYDRODROME

Abstract

Mugilids, in particular Mugil cephalus and Mugil capito have an economic importance in several parts of the world. Their collected fry from the Mediterranean in the last years became very valuable and expensive as a result of haphazard illegal collection and from the other side as a result of pollution of some of the natural sources.

The increasing number of fish farms in Egypt which depend mainly on farming mugilids suffer from deficiency of fry. This situation neccessitates an urgent plan for artificial production of grey mullets fry to substitute the shortage in fry.

Mariut company for fish farming have recently succeeded in receiving fry of Mugil cephalus artificially spawned in the farm of the company at the west of Alexandria.

The present work is an endeavor to determine the suitability of Mugil cephalus and Mugil capito transplanted into the Hydrodrome for artificial spawning, beside the investigation of their fisheries parameters in this closed fresh water area.

To determine the age, fish scales were used. Annual ring was shown

to deposit on the scales in April following the increase of water temperature . . m spnng.