Food habits of two mullets inhabiting Iraqi marine waters, Northwest Arabian Gulf

Abstract

The food habits of 319 specimens of Klunzinger's mullet Planiliza klunzingeri (Day, 1888) and 325 samples of Greenback mullet P. subviridis (Valenciennes, 1836) from Iraqi marine waters, northwest Arabian Gulf were investigated from February 2020 to January 2021. The stomach contents were analyzed and quantified with the percentage of points and frequency of occurrence methods, as well as with some complementary indices and measures (vacuity, fullness and relative importance). The annual averages of feeding activity for both species were 80.6 and 82.6%, respectively, while the mean values of feeding intensity were 7.8 and 7.6 points/fish, respectively. The annual averages of the feeding index (%) were 38.9 and 38.1% for the two species, respectively, while the mean values of the vacuity index were 19.1 and 15.4%, respectively. Both species can be classified as gluttonous. Analysis of the stomach contents showed that both species were classified as detritivores. P. klunzengeri consumed detritus (62.1%), diatoms (12.7%), algae (10.7%) and high plants (8.4%), zooplankton (3.9%) and fish eggs (2.2%), while P. subviridis fed on detritus (60.4%), diatoms (12.8%), algae (12.0%), high plants (9.3%), zooplankton (3.6%) and fish eggs (1.9%). Analysis of food similarity between P. subviridis and P. klunzengeri showed high similarity for the food items according to the Jaccard similarity index.