Observations on the Population Characters of Eared Horse Mussel, Modiolus auriculatus (Krauss, 1848) in the Red Sea, Egypt

The population analysis of 240 Modiolus auriculatus individuals collected from the Red Sea showed that its size ranged from 1.36 cm to 6.02 cm in shell length. During spring and summer seasons, most abundant shell size groups of average shell length 4.0 cm, 5.0 cm and 6.0 cm were observed. While during autumn and winter seasons the groups of 1.5 cm, 2.0 cm and 2.5 cm were found in the population. Sex ratio (males to females) being 1.2:1 and the proportion of sexes in all size groups did not differ significantly from 1:1. The seasonal meat yield values are higher in spring and summer than these values during autumn and spring seasons. This looked to be related to gonad condition more than the somatic growth of the animal.