A STATISTICAL STUDY OF LENGTH-WEIGHT RELATIONSIUP OF EIGHT EGYPTIAN FISHES

A STATISTICAL STUDY OF LENGTH-WEIGHT RELATIONSIUP
OF EIGHT EGYPTIAN FISHES
By
SAMIR ZAKY RAFAIL
Institute of Oceanography and Fisheries, Kayed Bey_ Alexandria,

Egypt

ABSTRACT
This study is presented to help to fill a. gap of a few published
length/weight statistical analyses. Fish weights (W) and their
logarithms (log W) gave evidences to approximate the normal distribution. One fish from eight gave an evidence of a homogeneouB
log W-variance. Polynomials of the third and fifth, second and third,
and second and fourth degrees fitted to fish length (L) and W, log L
and log W, and to Land W/L respectively previded log W-estimates
significantly different from empirical values. The equation, W =
aLD, fitted to longer or shorter length ranges (Ma.y be stanzas), gave
insignificant differences between calculated and empirica.l estimates
and took the cubic form in two fishes. This implies that fish volume
may be directly proportional to the product of L and a mean-crossseotional area determined by two axes related to L by a power equation