بررسي شاخص تراكم و اندازه طولي صدف هاي مرواريدساز محار Pinctada radiata در دو زيستگاه در اطراف جزيره هندورابي (ايران، خليج فارس)

سواحل و آب هاي كم عمق مناطق غربي استان هرمزگان، همواره از زيستگاه هاي طبيعي مهم صدف هاي مرواريدساز به شمار مي رفته است. بر اساس مطالعات Lorimer در سال 1915، زيستگاه هاي دريايي واقع شده در استان هرمزگان، عمده ترين ذخاير طبيعي صدف هاي مرواريدساز را در سواحل شمالي خليج فارس به خود اختصاص مي داده است و صيادان به صيد صدف ها و استحصال مرواريد مشغول بوده اند (Carter, 2005). صيد بي رويه صدف در اين منطقه تا قبل از دهه 70 شمسي ادامه داشته كه منجر به كاهش شديد ذخاير صدف مرواريد ساز لب سياه Pinctada margaritifera شده است (حسين زاده صحافي، 1372).

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.