Feeding Ecology and Prey Preference of Grey Mullet, Mugil cephalus (Linnaeus, 1758) in Extensive Brackish Water Farming System

Abstract

Feeding ecology and prey preference of Mugil cephalus reared in extensive brackish water farming system was studied based on monthly examination of stomach contents over a period of 10 months (February-November, 2014). Feeding intensity, planktonic constituents in water and food constituents in the stomach were estimated numerically. The percentage compositions of food items in the stomach falling under different groups were then compared with that of fish pond to evaluate prey preferences. Lower feeding intensity was observed during the initial months which gradually increased as the fish's grew. The dominant phytoplankton groups in pond water according to the order of dominance were Chlorophyceae, Bacillariophyceae and Myxophyceae. Most abundant zooplankton group was Dinoflagellates followed by Copepods. The main phytoplankton groups found in the stomach according to the order of dominance were Bacillarophyceae, Chlorophyceae and Myxophyceae. Dominant zooplankton group in the stomachs were Dinoflagellets followed by copepods. Prey preference analysis revealed that M. Cephalus actively selected Bacillariophyceae as most preferred food material. Myxophyceae was also selected as second preference. Chlorophyceae was not at all selected and was probably swallowed mechanically during intake of other food stuffs. True positive selection of copepods during initial months of rearing indicates preference by M. cephalus juveniles.

Feeding ecology, prey selection and growth performances of gold spot mullet, Liza parsia (Hamilton, 1822) in extensive brackish water farming system of Indian Sundarbans

“…Concentrations of toxic metabolites like nitritenitrogen (NO2-N)and ammonia-nitrogen (NH4-N) remained lower than the critical level and concentrations of nutrients like nitrate-nitrogen (NO3-N) and phosphate-phosphorous (PO4-P) was much lower than fertilized ponds reported from Sundarbans [4,28] and corroborated with those reported earlier by Mondal et al [29] from the same location. Lower nutrient concentrations in the studied extensive system may be attributed to complete dependence on natural productivity without any additional input.…”

“…Fish and shrimp parts and dinoflagelets were not at all selected by L. parsia. Order of preference of phytoplanktonic food by L. parsia as myxophyceae>bacillariophyceae>chlorophyceae is different from coexisting species like Mugil cephalus L bacillario phyceae>myxophyceae>chlorophyceae [29] and Liza tade as ch lorophyceae>myxophyceae>bacillariophyceae [38] in the same environment suggests feeding strategy of mullets to reduce inter specific competition within the same tropic level.…”

Feeding behavior and growth performance of tade mullet, Liza tade (Forsskail, 1775) in brackish water gher farming system

“…Mullets have been reported that they are chiefly plankton feeders [49,50]. Bacillariophyceae followed by myxophyceae and Chlorophyceae as most dominant food constituents of M. cephalus in brackishwater environments have been reported from various parts of Indian subcontinent [7,51,52] and other parts of the world [53][54][55][56]. Planktonic algae were reported to be the dominant food item of gold spot mullet, L. parsia and planktonic groups according to the order of dominance were Chlorophyceae, Bacillariophyceae and Myxophyceae [57].…”

Food and feeding habits of the greenback grey mullet Liza subviridis (Valenciennes, 1836) from Parangipettai waters, south-east coast of India

“…Studies in Mugil cephalus also observed preference for diatoms (Tandel et al, 1986;Khan and Fathima, 1994;Rao and Sivani, 1996;Bekova et al, 2013;Rao and Babu, 2013;Modou et al. 2014;Mondal et al, 2015). Blaber (1976) as well as Wijeyratnae and Costa (1990) noticed high proportion of sand in the stomachs of grey mullets.…”

“…Grey mullets are typically bottom feeders subsisting on decayed organic matter, fresh and decaying algae and diatoms (Jacob and Krishnamurthy, 1948;Pillay, 1953;Bond, 1979;El-Marakby et al, 2006;Mondal et al, 2015). From the results obtained presently it is clear that the food of different size groups of L. subviridis largely comprise of decaying matter, sand, diatoms, dinoflagellates and zooplankton.…”