Density index and length scale of Pearl Oyster Pinctada radiata in two habitats around Hendorabi Island (Iran, the Persian Gulf)

Abstract

As pearling has been banned in Iran since 2006, stocks of pearl oysters has not been investigated during these years therefore, condition of natural habitats for Pinctada radiata in its old habitats was surveyed in present research. Shallow waters around Hendorabi Island were searched with diving and two habitats namely “Sooleh” and “Sahel-e-sheni”, were considered for study. The pearl oysters had most distribution in these habitats in depth ranges of 7 to 12 m and 8 to 11 m, respectively. Total stock in Sooleh and Sahel-e-sheni was surveyed near 35700 and 12563 Pinctada radiata, respectively, of which 22% and 67% were catchable, respectively. Catch Per Unit of Area (CPUA) in Sooleh and Sahel-e-sheni habitats was estimated equal to 0.3 N/m2 in both habitats, and Catch Per Unit of Effort (CPUE) in these habitats was calculated equal to 59.5 N/hr and 50.3 N/hr, respectively. Results of this study demonstrated that area, stocks and CPUA for studied habitats were less than previous years. Despite of interdict of pearling in this region since 7 years ago, stock revival has done slowly.

Keywords

• Mohar Pearl Oyster Pinctada radiata; density index; Length scale