RT - Journal Article T1 - Feeding habits and trophic level of Himantura gerrardi (Elasmobranchii; Dasyatidae) in northern Oman Sea: effects of sex and size class JF - IFRO YR - 2018 JO - IFRO VO - 17 IS - 1 UR - http://jifro.ir/article-1-3274-en.html SP - 137 EP - 150 K1 - Dasyatidae K1 - Himantura gerrardi K1 - Feeding habits K1 - Trophic level K1 - Oman Sea. AB - The feeding habits and trophic level of Himantura gerrardi were studied according to sex and size classes of 80 individuals obtained using bottom trawl between May and December 2014 from the Oman Sea. Collected specimens were divided into three size classes (small<38 cm, medium 38-58 cm and large>58 cm) based on disk width. Prey was identified in seven main zoological categories, where crustacean and polychaetes were the dominant in diets, indicating this species is a demersal dwelling species. No significant differences were observed between sexes, but size classes showed significant differences in their diets. Also, results showed a decrease in feeding overlap between size classes with an increase in disk width, suggesting that intraspecific competition reduced, which allows the coexistence of different size classes. Trophic level was positively correlated with the disk width, which was lower than 4.0 for both sexes and different size classes, placing it in an intermediate trophic level. LA eng UL http://jifro.ir/article-1-3274-en.html M3 ER -