International Journal of Aquaculture, 2015, Vol.5, No.6, 1
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3
1
A Letter Open Access
Food and feeding habits of Mugil cephalus of Kayamkulam estuary, Kerala
K.S.Anila Kumary
Department of Zoology, Kuriakose Gregorios College, Pampady, Kottayam-686502, Kerala, India
Corresponding author Email
International Journal of Aquaculture, 2015, Vol.5, No.6 doi: 10.5376/ija.2015.05.0006
Received: 21 Feb., 2015
Accepted: 02 May., 2015
Published: 14 May., 2015
Copyright © 2015 Kumary, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article:
Kumary, 2015,
Food and feeding habits of Mugil cephalus of Kayamkulam estuary, Kerala, International Journal of Aquaculture, Vol.5, No.6: 1-3 (doi:
Abstract
Estimates of gut contents are important prerequisites for fishery biological investigations. Food and feeding habits of
Mugil cephalus
of Kayamkulam estuary (9
0
2’-9
0
19’N latitude and 76
0
26’-76
0
32’ E longitude) were observed on 160 specimens
collected at monthly intervals during May-Dec.2010. The values of RLG varied between 2.1-3.35 indicating the omnivorous feeding
habit of the fish. Feeding intensity analysis revealed the predominance of poorly fed fishes in the estuary. Proportion of actively fed
fishes was maximum (33.34%) during October. Gut contents of the fish comprise diatoms, decayed organic matter, fresh and
decomposing algal matter together with sand and mud. Diatoms contribute 58.94% of the total gut contents.
Keywords
Feeding intensity; RLG; Gut contents;
Mugil cephalus
Introduction
Food and feeding habits is one of the basic aspects of
the biology of fish on which its behaviour, habits,
morphology and even life cycle depends. Feeding
habits of fishes vary according to the amount and type
of food present in a particular environment.
Information on food and feeding habits is of utmost
importance not only for commercial purpose but also
for formulation of policy for effective management of
its fishery.
Mullets comprise the most important group of fishes
that contribute to the fisheries of estuaries, backwaters
and inshore areas. Grey mullet
Mugil cephalus
(Linnaeus) is a widely distributed coastal teleost in
temperate and tropical waters and is a universally
successful species having highest potential for
artificial rearing in brackish water environment.
Kayamkulam estuary (9
0
2’ – 9
0
19’N latitude and
76
0
26’ – 76
0
32’E longitude) on the south west coast of
India is far richer in availability and abundance of
grey mullets and the commercial catches of the
estuary present interesting prospects of mullet fishery
in the estuary.
1 Materials and Methods
A random sample of 160 specimens of
Mugil cephalus
,
consisting of different size categories, ranging in total
length from 110-202 mm and in total weight from
15.14-104.5 g were examined for total length, total
weight, gut length, relative length of gut, feeding
intensity and stomach contents. Fishes were collected
from the cast net catches of the estuary at monthly
intervals during the period May – December 2010.
Volumetric and numerical methods (Pillay, 1952) were
employed for the analysis of stomach contents. The
intensity of feeding was determined on the basis of
stomachs fullness ranging from full, ¾ full, 1/2 full, ¼
full and empty. For calculating relative length of gut
(RLG) the gut length was divided by the total length
of fish. The data on total length of fishes was
categorized in to 10 size groups and the gut length and
RLG were estimated for the different size groups
while monthly estimates were taken on feeding
intensity and gut contents analysis. For identification
of food organisms standard literature such as Newell
and Newel (1977) and Conway et al
.
(2003) were
referred.
2 Results and Discussion
The relationship between gut length and body length
has been widely used as an indication of the diet of
fishes. The values of RLG calculated for the different
length groups of
Mugil cephalus
collected from
Kayamkulam estuary is presented in Table 1. In
carnivorous fishes RLG values are generally low
while herbivorous fishes have higher RLG values
.
Mugil cephalus
is a widely distributed coastal teleost,
