1. Diet Composition of Two Most
Common Fish Larvae in the Sungai
Pulai Seagrass Bed, Johor,
Peninsular Malaysia
By
A. ARSHAD, ROUSHON A., S.M.N. AMIN, S.K. DAUD
& MAZLAN A G
Laboratory of Marine Science & Aquaculture
Institute of Bioscience
Universiti Putra Malaysia
2. INTRODUCTION
Studies of fish larvae are often the best way
to provide information of great value to
managers of fishery resources
These include location of spawning grounds in
term of space and time; type of habitats
used by fish during their larval phase; and
what kind of foods being taken.
Different larval stages, consume different
diets; composition of diets reflected by
stomach content study is important for
3. INTRODUCTION Cont.
Feeding habits of fish larvae is essential for the
aquaculture purpose
Few ichthyological research particularly larvae and
lack of published reports on the diet composition
of fish larvae in the country
Therefore, study on food items which led to
determination of feeding habits were undertaken
4. O B J E C T IV E S
To determine the major food item
presents in the gut of two most common
fish larvae in the Sungai Pulai seagrass
beds
To analyse the importance of diet
composition based on simple resultant
index analysis
5. METHODOLOGY
Study area and Sampling
The study was conducted in the Seagrass bed
of Sungai Pulai Estuary (N 010 19.414/; E 1030
35.628/)
Monthly sampling from December 2007 to
May 2008 was carried out during new moon
period.
Samples of fish larvae were collected using
Bongo net (500 μm) through 30 min subsurface
net towing.
7. Sample Processing:
After tow, samples were immediately fixed
in 5% formalin and transported to the
laboratory for further analysis.
From the samples two most common family
viz. Terapontidae and Gobiidae were sorted
out and preserved in 75% alcohol.
Identification of the two families was done
using the references by Leis and Carson-Ewart
(2004); Kawaguchi (2002)
8. Stomach Examination:
The total length of the specimens were
taken using digital microscope
Then, their stomach was incised under
microscope with fine needles and contents
were examined.
The food items were identified to the
possible lowest taxa followed by counted
their number and frequency with a compound
microscope.
9. Data Analysis:
To analyze the composition of the stomach,
percentage frequency of occurrence and
percentage numerical abundance was
followed (Chrisafi et al., 2007).
The relative importance of food items in
the diet of Terapontidae and Gobiidae was
assessed by Simple Resultant Index (%Rs)
according to Mohan and Sankaran (1988)
11. Larva of the family Terapontidae
Larva of the family Gobiidae
12. Taxonomic Identification
Melanophore
Terapontidae:
Gut 1. Gut is coiled
Eye 2. Melanophore are on the
ventral surface of the gut
3.Eye is rounded but moderate
to large
4.Larvae are moderate to
large, deep and compressed
Melanophore
Gut
Gobiidae:
Eye 1. Gut is triangular
2. Melanophores are on the gut,
dorsal and ventral of the body
3. The eye is rounded
4.Larvae are elongated to
moderate in depth
13. Diet Composition
Food Groups Food Items
1. Phytoplankton Chromophyta, Dinoflagellate, Diatoms, Centric
Diatoms, Chlamydomonas, Coscinodiscus sp.,
Euglena sp., Gonyaulax sp. and Other Species
2. Zooplankton: Ostracod, Copepod, Amphipod, Isopod, Paramecium
sp., Larvaceans, Larval stage, Thaliacians
(Tunicates), Decapods Appendages and Mysid
3. Insects
4. Part of algae
5. Plant like matter Dried roots, stems, grass leaves and parts of
unidentified plants
6. Appendages of crustacean
7. Debris
8. Unidentified species
14. Some food items found in the guts of larvae
Centric diatom (100x) Copepod (100x)
Larval stage (Naupli) (100x)
15. Diet Composition of Terapontidae
Larvae
The Table 2 shows the monthly percentage
of occurrence (Fpi) of food items in 80 guts
of Terapontidae fish larvae
The highest percentage of occurrence was
the phytoplankton (80%) and the lowest
percentage was the appendages of
crustaceans (1%)
Differences in phytoplankton groups taken
with time
17. Diet Composition of Terapontidae
Larvae
Table 3 shows monthly percentage of
numerical abundance (Ci) of food items in
80 guts of fish larvae from family
Terapontidae
The predominant item recorded was
phytoplankton (67.52%) and were highest
for all sampling months
Chlorophyta was the most important
19. Diet Composition of Gobiidae
The monthly percentage of occurrence
(Fpi) of food items in 88 guts of fish
larvae from Gobiidae family are showed
in Table 4
The highest percentage of occurrence
for phytoplankton was found in January
(70%) and the lowest percentage was
insects (2.39%)
Copepods and ostracods were amongst
the major zooplanktons recorded
21. Diet Composition of Gobiidae
Table 5 showed monthly percentage of numerical
abundance (Ci) of food items in 88 guts of fish
larvae from family Gobiidae
The table also shows that the predominant item is
phytoplankton (63.47%)
Phytoplankton was consistently forming the top
food item consumed throughout the period of
observation
23. Overall Diet Composition
The phytoplankton was the highest rank
(60.85%) of food item found in the gut
of Terapontidae followed by algae
(11.73%), zooplankton (9.35%), plant
matter (7.84%) (Table 6)
25. Overall Diet Composition
For Gobiidae, the phytoplankton
(56.33%) was at the highest rank index
followed by plant matter (15.134%),
zooplankton (9.84%) and algae (9.73%)
(Table 7)
27. CONCLUSIONS
There were eight groups of food items in the
guts of both fish larvae (phytoplankton,
zooplankton, algae, insects, plant like matter,
appendages of crustaceans, debris and
unidentified items).
In Terapontidae, phytoplankton was the first
ranked by Simple Resultant Index (60.85%)
followed by algae (11.73%)
As for Gobiidae, the phytoplankton (56.33%) was
also the highest rank followed by plant like
matters (15.13%).
28. Universiti Putra Malaysia (UPM)
Universiti Kebangsaan Malaysia (UKM)
MOSTI Malaysia for the funding of the
project & travel grant
