AGE AND GROWTH OF STINGRAY DASYATIS PASTINACA IN THE EGYPTIAN MEDITERRANEAN WATERS OFF ALEXANDRIA.

AGE AND GROWTH OF STINGRAY DASYATIS PASTINACA
IN THE EGYPTIAN MEDITERRANEAN WATERS OFF
ALEXANDRIA.
A.K.HAMZA , A. A. EZZAT ., S.M. ALAAM’ & M.T. HASHEM
National Institute of Oceanography and Fisheries. A}exandrla.
*’Oceanography Department. Faculty of Science. Alexandria University.
ABSTRACT
Age and growth. of ~syatis pllstinaca
were determined by reading vertebrae. The
results showed that annual rings formed
during December-Aprl1 wIth a midpoInt In
February. .
Counts of growth rings on vertebral centra
were employed to back-calculate length at
ages for the full range (18-49 em 0.11.),
Hales and female!. had nearly slmllar growth
rates though fema 1 grows muct: longer’ than
males. The oldest female was 5 yean at
IJ7001 cm ilnd 3769 grams. wht1e thl; o1dcst
male …..ilS 4 \,,