SELECTIVITY OF GILL AND TRAMIYlEL NETS CFOR CYPRINUS

SELECTIVITY OF GILL AND TRAMIYlEL NETS CFOR CYPRINUS
CARPIO AND BARB US BYNNI OF THE NOZHA HYDRODROME
By
M.T. HASH EM, I.A. SOLIMAN -‘.ND A.A. AL-S-‘.YES

INTRODUCTION
Gill nets are considered to be one of the most important fishing gears of
the world. They are widely used in both marine and fresh water fisheries.
In Egypt; especially in inland waters (Nile and lakes), trammel nets are
also used on wide scale for fishing Tilapia and other fresh water fishes.
In order to evaluate the effect of mesh selection, comparative fishing
experiments were carried out in the Nozha hydrodrome from April till
December 1968, with both gill and trammel nets of four different mesh
sizes.
The present work is carried out to give a review of these experiments,
with the aim of studying the efficiency and selectivity of gill and trammel
nets for the common carp (Cyprinus carpio] and Barhus bynni of the
Nozha hydrodrome.
Place of erperimerus :
The experiments were carried out in the Nozha hydrodrome, which is
an isolated part of Lake Mariut (near Alexandria), having an area of 504
hectars and and average water depth of about six meters. The hydrodrome
is regularly supplied with fresh water from