Feeding Habits and Relative Condition Factor of Crenidens crenidens in Jeddah Fisheries, Saudi Arabia

الملخص

The present study investigates the gut contents and feeding habits of Crenidens crenidens in the Red Sea coast of Jeddah, Saudi Arabia. Gonadosomatic index, length-weight relationship and relative condition factor were also determined. Samples were collected monthly during the period from November 2018 to October 2019. Stomach contents were identified and assessed by the frequency of occurrence, numerical and gravimetric methods. The total number of specimens collected was 375, of which 139 were having empty stomachs. Feeding intensity was the highest between April (80.0%) and September (90.9%) and the lowest from November (27.8%) to January (16.7%) and February (41.2%). The maximum value of Fullness index (FI%) was found in Summer (88.11%) and lowest in Winter (26.42%). Whereas the maximum value of Vacuity index (VI%) in Winter (73.56%) and lowest in Summer (11.89%). The results showed that C. crenidens mainly feeds on seaweeds, seagrasses, small mollusks and nematodes, and thus it is omnivorous fish.  Seaweeds were the most important food items (IRI%, 38.33), then seagrasses (IRI%, 29.9) and unidentified small plant parts (IRI%, 22.0). The length-weight relationship could be described by the power equation: W = 0.0173 L3.00 (R2 = 0.96) where the slope 'b' equal to '3' indicating that the growth of this species is isometric. The relative condition factor Kn was found affected by the feeding intensity and spawning activity.