Faculty of Resource Science and Technology

TETRAODON FISH COMMUNITY STRUCTURE AND GUT CONTENT ANALYSIS IN COASTAL AND MANGROVE AREA S OF LUNDU, , ASAJAYA AND KOTA SAMARAHAN

THIAN ZHI LIN

Bachelor of Science with Honours (Aquatic Resource Science and Management ) 2015

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TETRAODON FISH COMMUNITY STRUCTURE AND GUT CONTENT ANALYSIS IN COASTAL AND MANGROVE AREAS OF LUNDU, SEMATAN, ASAJAYA AND KOTA SAMARAHAN

Thian Zhi Lin

This project is submitted in partial fulfilment of the requirements for the degree of Bachelor of Science with Honours (Aquatic Resource Science and Management)

Faculty of Resource Sciences and Technology UNIVERSITI MALAYSIA SARAWAK 2015

ACKNOWLEDGEMENT

I would like to use this opportunity to express my appreciation to everyone who gave me the opportunity to complete this report in time. Firstly, I would like to express gratitude to my final year project supervisor, Dr. Khairul Adha A. Rahim and his graduate students, who had given me suggestions and guidance to prepare this project report. I would also like to acknowledge with much appreciation to the lab assistants of UNIMAS, Mr. Zulkilfi

Ahmad, Mr. Zaidi Ibrahim, Mr Mohd Norazlan Bujang Belly and local fisherman, Mr.

Alang for providing me the facilities and equipments that are needed to carry out my research and their assistance during field work sampling.

Deepest thanks to other lectures as well as the panels as they have given me valuable comment and tips to help me improved my presentation skills during the project presentation.

Last but not least, I would like to express my warm thanks to my parents, family and friends for their cooperation, encouragement and friendly advice for the project report completion, from start till the end.

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DECLARATION

I hereby declare that the submitted contents of the work are original in its figure, excluded those specifically cited references that have been acknowledge. All the project works included are based on my own idea and creativity.

Thian Zhi Lin

Department of Aquatic Science

Faculty of Resource Science and Technology

Universiti Malaysia Sarawak

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TABLE OF CONTENT

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ACKNOWLEDGEMENT i DECLARATION ii TABLE OF CONTENT iii LIST OF ABBREVIATION v LIST OF TABLES vi LIST OF FIGURES vii LIST OF APPENDICES viii ABSTRACT 1 ABSTRAK 1 1.0 INTRODUCTION 2 2.0 LITERATURE REVIEW 4 2.1 Distribution 4 2.2 Characteristics of Tetraodontidae Fish Distributed in Sarawak 5 2.3 Feeding Behaviour 6 2.4 Puffing Behaviour 7 2.5 Reproduction 7 3.0 MATERIALS AND METHODS 8 3.1 Field Work 8 3.1.1 Study Area 8 3.1.2 Description of Study Areas 10 3.1.3 Sampling 11 3.1.4 Physicochemical of Water 11 3.2 Laboratory Work 12 3.2.1 Species Identification 12 3.2.2 Physical Measurement 12 3.2.3 Gut Content Analysis 13 3.3 Data Analysis 14 3.4 Statistical Analysis 15

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4.0 RESULTS AND DISCUSSION 16 4.1 Physicochemical Water Quality Parameters 16 4.2 Fish Composition 18 4.3 Morphometric Measurement of Fish Collected 21 4.4 Tetraodontidae Fish Used for Gut Content Analysis 23 4.5 Gut Relative Index (GRI) 24 4.6 Food Composition 26 4.7 Frequency of Occurrence 30 4.8 Diversity Indices 32 4.9 Correlation Analysis 33 5.0 CONCLUSION 34 6.0 REFERENCES 35 7.0 APPENDICES 39

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LIST OF ABBREVIATION

TTX Tetrodotoxin

TL Total Length

SL Standard Length

BW Body Weight

GL Gut Length

GW Gut Weight

DO Dissolved Oxygen

H’ Shannon-Wiener’s Diversity Index

D Margalef’s Species Richness Index

J’ Pielou’s Evenness Index

GPS Global Positioning System

GRI Gut Relative Index

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LIST OF TABLES

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Table 1: Description of coastal and mangrove study areas in Lundu, 10 Sematan, Asajaya and Kota Samarahan.

Table 2: Physicochemical water quality parameters at the study sites 16 (mean ± SE).

Table 3: List of fish composition found at the study sites . 18

Table 4: Mean of total length (cm), standard length (cm) and body 21 weight (g) of the fish samples (mean ± SE). Table 5: Total number of Tetraodontidae species used for gut content 23 analysis. 24 Table 6: Gut relative index (GRI) of the fish samples (mean ± SE).

Table 7: Food composition in fish stomach (%) for the fish dissected. 26

Table 8: Frequency of occurrence (%) of food in fish stomach. 30

Table 9: Diversity indices of fish collected. 32

Table 10: Pearson correlation coefficient between water 33 physicochemical parameters and number of fish individuals.

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LIST OF FIGURES

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Figure 1: Map of study sites- 1 (Sungai Sematan), 2 (Telok Melano), 9 3 (Teluk Belungi), 4 (Pandan Beach), 5 (Sungai Melaban) and 6 (Asajaya Laut).

Figure 2: Pictures of Tetraodontidae fish collected from study sites. 19

Figure 3: Percentage (%) of Tetraodontidae species found in the study 19 areas.

Figure 4: Total length (cm), standard length (cm) and body weight (g) 22 of the fish samples.

Figure 5: Gut relative index (GRI) of the fish samples. 25

Figure 6: Food composition in fish stomach for the fish dissected. 27

Figure 7: Pictures of food items found in fish stomach. 29

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LIST OF APPENDICES

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Appendix 1: Total length (cm), standard length (cm), body weight (g) 39 and gut length (cm) of fish samples.

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TETRAODON FISH COMMUNITY STRUCTURE AND GUT CONTENT ANALYSIS IN COASTAL AND MANGROVE AREAS OF LUNDU, SEMATAN, ASAJAYA AND KOTA SAMARAHAN

Thian Zhi Lin

Department of Aquatic Science Faculty of Resource Sciences and Technology Universiti Malaysia Sarawak (UNIMAS)

ABSTRACT

This study was carried out to document the community structure of tetraodon fish in coastal and mangrove areas of Lundu, Sematan, Asajaya and Kota Samarahan in September, October, November, 2014 and March, April, 2015. Habitat preference of the fish was identified based on the variety of Tetraodontidae species found in different locations. The feeding behaviour of Tetraodon species was evaluated based on the Gut Relative Index (GRI), food composition and frequency of occurrence of food items in the fish gut. A total of 42 fish samples were caught. This included four Takifugu oblongus , 24 Tetraodon nigroviridis , six Lagocephalus lunaris and eight Xenopterus naritus . About 22 fish gut content were observed. The results of food analysis showed that major food items were molluscs (38.00%), crustacean (29.00%) and fish skeleton (11.00%).

Key words: Feeding behaviour, gut content, food composition

ABSTRAK

Kajian ini telah dijalankan untuk mendokumentasikan struktur komuniti ikan tetraodon di kawasan pesisiran pantai dan bakau di Lundu, Sematan, Asajaya dan Kota Samarahan Samarahan pada September, Oktober, November, 2014 dan Mac, April, 2015. Keutamaan habitat ikan dikenalpasti berdasarkan berapa jenis spesies Tetraodontidae yang didapati di lokasi yang berbeza. Tabiat pemakanan spesies Tetraodon dinilai berdasarkan Indeks Relatif Perut, komposisi makanan dan kejadian frekuensi di dalam usus ikan. Sebanyak 42 sampel ikan ditangkap. Ini termasuk empat Takifugu oblongus, 24 Tetraodon nigroviridis, enam Lagocephalus lunaris dan lapan Xenopterus naritus. Hanya 22 kandungan usus ikan yang dianalisis. Keputusan analisis makanan menunjukkan bahawa makanan utama ialah moluska (38.00%), krustasea (29.00%) dan rangka ikan (11.00%).

Kata kunci : Tabiat pemakanan, kandungan usus, komposisi makanan

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1.0 INTRODUCTION

Puffer fish belong to the Tetraodontidae family, order Tetraodontiformes which have occured since 40 million years ago. About 185 species and 28 genera of puffer fish that are categorized under Tetraodontidae have been identified (Oliveira, 2006). According to Aydin (2011), approximately 120 Tetraodontidae species inhabit in tropical seas.

Kalogirou (2013) stated that puffers are widely distributed in tropical and temperate regions.

Puffer fish are considered the second most poisonous vertebrates in the world after the golden poison frog. Internal organs such as liver and gonads of some puffer fish contain tetrodotoxin (TTX) that are produced by the symbiotic bacteria,

Pseudomonas and Vibrio which inhabit the intestinal tract of puffers (Sabrah et al ., 2006;

Arakawa et al ., 2010). TTX is a nonprotein toxin (Kheifets et al ., 2012). When ingest TTX, symptoms will begin by feeling breathlessness, numbness, lethargy and even vomiting.

Evans (1969) mentioned that this toxin will inhibit action potentials by blocking the passage of sodium ions through ion channels and thus affect the neurone transmission in skeletal muscles. Other than being utilized as defensive mechanism, female puffers will release TTX as pheromone to attract males (Sousa, 2011).

However, tigersharks can feed on puffers because they are immune to the toxin.

Puffer fish meat is commonly consumed in Japan, Korea and China through preparation by trained chefs with the viscera and bile in the eggs discarded completely before cooking to avoid poisoning (Sabrah et al ., 2006; Hajeb et al ., 2012). In Betong, Sarawak, ‘yellow puffer fish festival’ is celebrated annually with a diverse of yellow puffers’ cuisines displayed and sold (Azman and Norhana, 2013).

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Puffers have slow locomotion and possess good eyesight and tail fins for speed burst to escape from predators. When threatened, tetraodon fish gulp air or water to puff up until they are too large for their predators’ mouth (Sabrah et al ., 2006). Some fish have spines at the dorsal part to protect themselves from attacked by predators (Mohamad and

Isa, 2013).

Puffer fish can live up to 10 or more years. However puffers do not possess any gill or scales, which causes they attacked by diseases easily. Mat Piah (2011) stated that puffer fish can survive well in natural environment. However pollution and habitat exploitation will endanger their lives. Since puffer fish are widely distributed and have long lifespan, they can be used as biomonitors to indicate the contaminant levels in water (Mat Piah and

Bucher, 2014).

This research was carried out to document the information on the species composition and gut content analysis from Tetraodontidae found in coastal and mangroves areas Lundu, Sematan, Asajaya and Kota Samarahan. This research can also examined about the food source available at the sampling sites that influenced the feeding behaviour of puffers. The objectives of the study were to determine the species composition and community structure of puffer fish in coastal and mangrove area in Asajaya, Lundu,

Sematan and Kota Samarahan, and to analyse gut content of Tetraodontidae fish in the sampling area.

The result of this study will provide important information for future cases study about the habitat, feeding behaviour, and distribution of puffer fish in the coastal and mangrove areas in Sarawak.

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2.0 LITERATURE REVIEW

2.1 Distribution

Puffer fish are distributed worldwide in tropic and subtropical area. Around 100 different kinds of puffer fish are found in shallow seas in Atlantic, Pacific and Indian

Oceans (Kalogirou, 2013). Puffers are adapted to brackish water, where river mouth meets with open sea, some are freshwater species and others are marine species. Monaliza and

Samsur (2011) stated that in Malaysia, at least 16 tetraodon species have been recorded whereas in Sabah and Sarawak, 12 marine species have been identified (Alias, 2013).

Tetraodontidae that live in marine are Lagocephalus lunaris , Lagocephalus spadiceus and Lagocephalus sceleratus (Mohamad and Isa, 2013). Carinotetraodon salivator is a freshwater puffer that is found in Sarawak water (Lim and Kottelat, 1995;

Khairul Adha et al ., 2009). Tetraodon nigroviridis is the brackish water species (Mahmud et al ., 1999). Around 39 species puffer fish will enter freshwater for a short time just for feeding or breeding, while others live entirely in brackish water, whereas 25 species spend their lives entirely in freshwater.

Kalogirou (2013) found that puffers live in large stream with soft and silty or sandy bottoms as Lagocephalus sceleratus were found abundant on sandy bottoms. Khairul Adha et al . (2009) also stated that Carinotetraodon salivator was found inhabit the brown water river in Batang Kerang that has high sediment content. Puffer fish also inhabit mangrove area that can serve as feeding ground for tetraodontidae with abundant food sources such as fish, crabs and prawns (Dankwa and Gordon, 2002; Mat Piah, 2011)

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2.2 Characteristics of Tetraodontidae Fish Distributed in Sarawak

Different species of Tetraodontidae fish have different morphological characteristics. According to Monaliza and Samsur (2011), Lagocephalus lunaris, L. spadiceus and L. sceleratus are the common species that can be found in Malaysian water.

These fish inhabit in Batang Sadong and Sampadi in Sarawak water (Azman et al ., 2014).

L. lunaris is a green rough-backed puffer with elongated body of metallic gold. It has a broad silvery band at the longitudinal line of lateral body that extend from the mouth until border of caudal fin. Its spines are distributed in elliptical shape at the dorsal body

(Mohamad and Isa, 2013).

L. spadiceus has tail near to dorsal fin which makes it resembles tadpole (Monaliza and Samsur, 2011). It’s back and sides of body are in darker gold colour with silvery belly.

L. sceleratus, silver-cheeked toadfish is brownish colour with black spots on upper part of body. Its silver band elongated from mouth until caudal fin. It also has white belly and black pectoral base. Its belly and dorsal body is covered with spinules.

Xenopterus naritus is yellow pufferfish that is abundant in estuaries in Sarawak including Batang River, Batang Sadong, Batang Saribas, Batang Krian and Batang Lupar

(Hajeb et al., 2012). Azman and Norhana (2013) described that this fish is light brown and gold colour on the back. Its belly is in yellow with no stripes and rounded spots covered covered around the body.

Nik (2011) stated that Carinotetraodon salivator is a stripped red-eye puffer that can be found in and Rajang Basin. Lim and Kottelat (1995) described that C. salivator has a pair of red eyes near the dorsal part of the head with whitish belly. Female will have bigger body size than male with cream-coloured striped ventrum whereas male has bluish-grey cross-banded ventrum (Lim and Kottelat, 1995). Due to its attractive

5 appearance, Carinotetraodon salivator had been traded as aquarium fish (Khairul Adha et al ., 2009).

Tetraodon nigroviridis which is known as spotted green puffer is a green colour puffer with white belly (Muthukrishnan, 2010). It is usually found in Sungai Sarawak and

Sungai Kuap (Atack, 2006). Its body possess small spinules and dorsal part is covered with rounded black or brown spots. Young of T. nigroviridis is more greenish and when it grows up, the body colour will turn more brownish. Tetraodon biocellatus that is commonly known as eyespot puffer is deep brown colour on the upper part of body with white belly. Its dorsal body is covered with yellow spots and lines.

2.3 Feeding Behaviour

Puffer fish possess four teeth that are large and are fused into both upper and lower plate resembling a beak (Mohamad and Isa, 2013). These teeth are so strong and therefore used to crush the hard shells of their prey such as crustaceans and molluscs. Puffer fish mostly consume invertebrates, corals, echinoderms and cephalopod (Krumme et al ., 2007).

According to Mohamad and Isa (2013), Lagocephalus lunaris is carnivorous fish as the fish main diet is crustaceans, fishes, cephalopods and molluscs. Tan (2004) stated that

Xenopterus naritus is an omnivorous as the gut content not only including the bivalves, gastropods, nematodes, polychaetes, but also algae. This statement is supported as the gut content of X. naritus also consist leaves fragments in the study carried out by Alias (2013).

As for Tetraodon nigroviridis , this fish is considered as omnivorous due to the study carried out by (Muthukrishnan, 2010) that the stomach of this fish contained gastropods, crabs, copepods, polychaetes and also fraction of roots. Based on the research done by Aydin (2011), Lagocephalus sceleratus shows the properties of carnivorous as the main diet of this fish is shrimps, crabs, fishes, squids and cuttlefish.

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2.4 Puffing Behaviour

Puffer fish have a defensive mechanism to defense themselves from predators by inflate their bodies. This puffing behaviour is found in the pufferfish from taxa

Diodontidae and Tetraodontidae. Brainerd (1994) noted that when puffer fish encounter with the predators, this fish will gulp water or air into their extensible stomach.

In order to achieve the inflation, puffer fish have sac that is attached to the intestines. When their stomach and esophagus are closed with a kind of muscular valve, their specialized gills will operate like a suction pump to fill the sac. As puffer fish lack of pelvic bones or ribs, they can expand their bodies into larger size (Wainwright and

Turingan, 1997). The collagen fiber organisation is modified, therefore the skin is extensible (Brainerd, 1994). When they feel safe, they will revert to their actual size by transfer the water out.

2.5 Reproduction

When puffer fish are sexually mature, spawning will occur when males guide females to a water surface pursue the females (Honma et al ., 1980). Females lay three to seven eggs with the youngs are protected inside their hard shells before they develop the limbs and hatch within a week (Mat Piah, 2011). When the fish grow up, they will swim to the reef community below.

Stroud et al . (1989) stated that Canthigaster valentini in Great Barrier Reef of

Australia, which is well-known as sharpnose pufferfish, will lay the eggs that attached to the algae. Siaw (2008) noted that for Xenopterus naritus and Tetraodon nigroviridis , both species spawn in brackish water. However X. naritus will lay eggs in nest whereas T. nigroviridis release their eggs on particular substrate.

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3.0 MATERIALS AND METHODS

3.1 Field Work

3.1.1 Study Area

The puffer fish samples were collected from mangrove and coastal area in Asajaya,

Lundu, Sematan and Kota Samarahan, Sarawak in September, November, October 2014 and March 2015. Asajaya is a small town located under .

Tetraodontidae fish samples were collected from Asajaya Laut which is located near to mangroves area that leads to the formation of brackish water there. Other sampling areas were Teluk Belungi and Pandan Beach in Lundu which are located in northwest of

Sarawak. Fish were also collected from Sungai Sematan which is located 29km away from

Lundu town. It is a fishing village that is located on the west-north-west of . Fish samples are also collected from Telok Melano which is a small Malay village located about

45 minutes from Sematan. Another sampling location is Sungai Melaban which is a stream located in Kota Samarahan, Sarawak that lies on the east of Kuching (Figure 1).

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), 5 ), (Sungai Melaban) and (Telok Melano), 3 Melano), (Telok (Teluk Beach Belungi), 4 (Pandan 6 (Asajaya Laut).6 (Asajaya Figure 1: Map of studyFigure 1: of Map sites- 1 (Sungai Sematan), 2

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3.1.2 Description of Study Areas

Table 1 described the characteristics of the sampling locations including Asajaya

Laut, Teluk Belungi, Sungai Sematan, Sungai Melaban, Telok Melano and Pandan Beach.

Table 1: Description of coastal and mangrove study areas in Lundu, Sematan, Asajaya and Kota Samarahan.

Study area Coordinate Description Asajaya Laut N01°35’49.0’’ Asajaya Laut consists of peat swamp that E110°36’12.4’’ extends from Sungai Samarahan until Batang Sadong that makes this environment a brackish area. It is surrounded by Nipah trees and mangrove forest.

Teluk Belungi N01°46’27.8’’ Teluk Belungi is a coastal indentation E109°50’48.9’’ between two headlands. The sandy bay is 600m long and extended from Pandan Beach.

Sungai Sematan N01°47’53.0’’ Sungai Sematan is a tidal creek with large E109°47’10.5’’ extended mangrove area next to the stream.

Sungai Melaban N01°28’04.2’’ Sungai Melaban is a stream that is E110°26’43.2’’ surrounded by Nipah trees and mangroves. Both sides of Sungai Melaban are mudflat areas.

Telok Melano N01°47’99.3’’ Telok Melano is a white sandy beach with E109°49’78.5’’ clear blue waters. It is surrounded with isolated islands.

Pandan Beach N01°45’93.3’’ Pandan Beach is a secluded, peaceful beach E109°51’66.2’’ that is not far from Teluk Belungi.

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3.1.3 Sampling

Samplings were carried out in Asajaya, Lundu, Sematan and Kota Samarahan.

Coordinate of the sampling site was recorded by using Global Positioning System (GPS) device (GARMIN GPSmap 62s). Puffers were collected by using gill nets with inner layer’ mesh size of 4cm and outer layer of 14cm . Gill net was set up in tidal channels on high tides and let it drifted with current at least ½ hour before collected the net. Floats were positioned along the top line of the net to maintain its vertical position in water. Flag and buoy were put beside the gill net to mark the location of the net. At low tide area, seine net with mesh size of 3.80cm, cast net with 1cm mesh size and scoop net were also used.

Physical measurement such as total length and standard length were measured by using ruler and measuring board to the nearest 0.10cm, while the body weight was weighed by using analytical balance to the nearest 0.01g. Fish samples were dissected in the field. The gut length and weight of the fish were measured then preserved with 5% formalin. The guts were put in bottle sample for further laboratory analysis.

3.1.4 Physicochemical of Water

Water samples were collected from Asajaya, Lundu, Sematan and Kota Samarahan.

Salinity was analyzed with the ATAGO PAL-06S pocket refractometer. Temperature and pH were recorded by using Milwaukee, MW100 pH meter. Turbidity of water was analyzed by using Lutron Tu-2016. As for dissolved oxygen (DO), DO meter from

EXTECH INSTRUMENTS, SDL 150 was used.

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3.2 Laboratory Work

3.2.1 Species Identification

Physical characteristic of puffers such as eyes, mouth, head, snout, spot pattern, body colour and distribution of spines were observed (Padate et al ., 2013) . Fish samples were identified until species level based on identification key feature following Inger and

Chin (1990), Kottelat and Lim (1995) and Atack (2006).

3.2.2 Phyical measurement

Total length (TL) and standard length (SL) of each puffer fish samples were measured by using a measuring board and ruler to the nearest 0.1cm. Body weights of the fish were weighed by using analytical balance to the nearest 0.01g (Monaliza and Samsur,

2011). Number of caudal fin, pectoral fin, dorsal fin and anal fin of each fish was counted and recorded.

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