رژیم غذایی کوسه چاک لب (1837 rhizoprionondon acutus (ruppel, در آب‌های خلیج فارس و دریای عمان (محدوده استان هرمزگان)

مقدمه: این مطالعه با هدف تعیین رژیم غذایی کوسه چاک لب (1837rhizoprionondon acutus (ruppel, در آب‌های خلیج فارس محدوده استان هرمزگان صورت گرفت. مواد و روش‏ها: تعداد کل نمونه های صید شده از آب‌های استان هرمزگان 45 قطعه شامل 17 نمونه نر و 28 نمونه ماده با نسبت جنسی نر به ماده 1.65 :1 در جمعیت بود.نتایج: براساس تجزیه و تحلیل های آماری اختلاف معنی‌داری بین نسبت جنسی نر و ماده در جمعیت این گونه کوسه وجود نداشت (0.05

diet of the milk shark, rhizoprionondon acutus (ruppel, 1837) in waters ofthe persian gulf and oman sea (hormozgan province)

introduction: the aim of this study was to determine the diet of the milk shark in watersof the persian gulf and the oman sea in hormozgan province.materials & methods: total number of samples collected from the waters of hormozganprovince was 45, of which, 17 and 28 were male and female, respectively.results: the sex ratio of male to female was 1:1.65 in the studied population, which showedno statistically significant difference between the sex ratio of male and female (x2=2.69,p>0.05). the results of frequency and weight percentage of the stomach contents showedthat the highest frequency and weight percentage (47.44 and 63.88%, respectively) wererelated to teleost fish and then crustaceans (33.33 and 23.30%, respectively). cephalopods(6.41% and 7.13%, respectively), other prey (8.97% and 3.71%, respectively) and bivalves(3.85% and 1.98%, respectively) were in the next ranks. results of food preference indexshowed that the fish food group had a total of 83.72 as the first preferred food of the milkshark. results of empty stomach index in the milk shark indicated that both males andfemales and the whole population in the coasts of hormozgan province is considered as agluttonous species. teleost fish had the highest relative importance of prey (iri) for bothmales and females and the whole population of milk sharks, (76.53, 67.73 and 73.71%,respectively). for the population and female sharks, crustaceans and bony fish had thehighest shannon-wiener biodiversity index with 0.159 and 0.153, respectively, but in malesharks, shannon-wiener biodiversity index showed the highest biomass index of bony fish(0.138) compared to crustaceans (0.114). gastrointestinal index (gsi) in r. acutus shark offthe coast of hormozgan province was 2.62% for males, 2.10% for females and 2.30% forthe whole population of this species.conclusion: the overall results show that a common pattern in the milk shark dietpreference is elucidated, in which small bony fish are seen as the most preferred prey,followed by crustaceans.