Abstract

Biological studies on Engraulis encrasicolus, a migrant species inhibiting Suez Canal (Lake Timsah and Great Bitter Lake) was studied during the period from May 2001 to October 2002. Its total length varied from 3.4 to 9.8 cm and average total body weight varied from 0.3 to 14.4 g. The length weight relationship were determined for 1654 specimens of both sexes combined (W= -1.957, L2.6852). The mean values of condition factor “K” and relative condition factor “Kn” were 0.62± 0.07 and 1.0 ± 0.07 respectively. The analysis of 317 stomachs revealed that Engraulis encrasicolus is a plankton feeder. Its main food items were mysedaca and polychaetes. About 300 individuals of the fish were used for studying the reproductive biology. Size at 50% maturity for males and females were estimated to be 7.2cm and 7.5cm respectively and sex ratio for M/F was 1:1.05. The average G.S.I of males was significantly lower than that of females. Females have a definite breeding season extends from February till July. The maximum average sizes of oocytes were recorded during June. The absolute fecundity ranged from 229 to 3321 eggs.

Key words: Engraulis encrasicolus, small fish, growth, feeding, reproduction, Suez Canal, Lake Timsah, Great Bitter Lake, Egypt