POPULATIONDYNAMICS OF TWO PICAREL SPECIES IN THE MEDITERRANEAN WATERS, EGYPT

POPULATIONDYNAMICS OF TWO PICAREL SPECIES IN
THE MEDITERRANEAN WATERS, EGYPT
By
s. L RlZKALLA·* .
·National Institute of Oceanography and Fi~heries, Alexandria,. Egypt.
key-wor.ds: Fish Population dynamics, Spicara smaris – Spicaraflexousa.
ABSTRACT’
Population dynamics of two fish stocks belonging to family:
Centracanthidae Spicara smaris (L.) and Spicaraflexousa (Raj) were
studied Samples were collected’during 1993 from the catch of the
Egyptian Mediterranean trawlers. Results revealed that, the fishing
mortality (F= 0.9508) and naturai mortality (M= 0.7933) for S~ smaris
was greater than those ofS.flexousa (F= 0.4168 and M= 0.4741). The
survival rate for s. flexousa” (S= 0.4103) was higher than. that of
S. smaris (S= 0.1748). The yield/recruitfor current level ofs. smaris
(3.77 g) was nearly similar to that obtainedfrom the maximum. economic
level (3. 88 g) whereas for s. flexousa. (9. 8 g) was less than the maximum
economic level (11.50 g) by about 14: 78%.