Sains Malaysiana 41(7)(2012): 855–861

Feeding Ecology and Food Preferences of Carcinoscorpius rotundicauda

Collected from the Pahang Nesting Grounds

(Ekologi Pemakanan dan Pemilihan Makanan Carcinoscorpius rotundicauda dari

Kawasan Tapak Penetasan Negeri Pahang)

B. Akbar John, B. Y. Kamaruzzaman* &K .C. A. Jalal

Institute of Oceanography and Maritime Studies

International Islamic University Malaysia, Jalan Sultan Ahmad Shah, Bandar Indera Mahkota,

25200 Kuantan, Pahang, Malaysia

K. Zaleha

Institute of Tropical Aquaculture, University Malaysia Terengganu

21030 Kuala Terengganu, Terengganu, Malaysia

Diserahkan: 18 Ogos 2011 / Diterima: 21 Februari 2012

ABSTRACT

The first time report on the feeding ecology and food preference of mangrove horseshoe crab Carcinoscorpius rotundicauda (Latreille 1802) at their nesting grounds along the Pahang coast is given. Monthly sampling was carried out between March 2010 and February 2011 covering both monsoonal (March to October) and non-monsoonal (November to February) seasons. Major macrobenthic gut contents (bivalves, gastropods, crustaceans, polychaetes and miscellaneous food items including plant materials) were identified using microscopic examination. An electivity index (E1) was calculated for the frequent food items observed in the gut region of C. rotundicauda during monsoon and non-monsoon seasons. The EI was negative for crustaceans and positive for all the other food items including bivalves, gastropods, polychaetes and miscellaneous food items (which include insects, amphipods, Isopods, larval and juvenile stages of fishes, foraminifera and other Annelid worms). It is interesting to note that C. rotundicauda prefered less number of bivalves than polychaetes during non monsoon seasons but it was the reverse during monsoonal period. Male crabs intensely preyed on gastropods and female prefers polychaete worms during the peak mating/nesting season (June - August 2010). Seasonal variations in food composition showed that mollusks formed the main item especially gastropods. Unidentified organic matters in the gut content analysis of C. rotundicauda showed high preference towards plant materials. Gastro Somatic Index (GaSI) analysis showed that the feeding intensity of male crabs was higher during non-monsoon period while it was higher during monsoonal period in female crabs. In conclusion, the feeding ecology of mangrove horseshoe crabs were more similar to its closer and distant conspecifics. However, it was postulated that the higher preference of polychaete worms by the female C. rotundicauda during the peak mating season indicated its role in regulating the nesting behaviour.

Keywords: Carcinoscorpius rotundicauda; electivity index; gastro somatic index; horseshoe crab nesting

ABSTRAK

Laporan pertama mengenai ekologi pemakanan dan makanan utama ketam ladam bakau Carcinoscorpius rotundicauda (Latreille 1802) di tempat bertelur di sepanjang pantai Pahang telah diberikan. Persampelan bulanan telah dijalankan antara Mac 2010 dan Februari 2011 yang meliputi kedua-dua musim monsun (Mac hingga Oktober) dan bukan monsun (November hingga Februari). Kandungan usus makrobentik yang utama (bivalvia, gastropod, krustasia, polichaetes dan bahan makanan yang pelbagai termasuk bahan tumbuhan) telah dikenal pasti dengan menggunakan pemeriksaan mikroskopik. Indeks elektiviti (EI) telah dikira untuk bahan makanan yang kerap diperhatikan di bahagian usus C.rotundicauda semasa musim monsun dan bukan monsun. Keputusan memberikan EI yang negatif untuk krustasia dan positif untuk semua bahan makanan lain termasuk bivalvia, gastropod, polichaetes dan bahan makanan yang pelbagai (termasuk serangga, amfipods, Isopod, larva dan peringkat juvenil ikan, foraminifera dan cacing Annelid yang lain). Adalah menarik untuk diperhatikan bahawa C.rotundicauda lebih cenderung kepada bilangan bivalvia yang lebih sedikit daripada polichaetes semasa musim bukan monsun tetapi adalah sebaliknya ketika tempoh monsun. Ketam jantan giat menjadi pemangsa gastropod manakala ketam betina cenderung pada cacing polichaete semasa puncak musim mengawan/bersarang (Jun – Ogos 2010). Variasi yang bermusim dalam komposisi makanan menunjukkan bahawa moluska membentuk bahan utama terutamanya gastropod. Bahan organik yang tidak dikenali dalam analisis kandungan usus C.rotundicauda menunjukkan keutamaan yang tinggi terhadap bahan tumbuh-tumbuhan. Analisis Indeks Gastro Somatik (GaS) menunjukkan bahawa keamatan pemakanan ketam jantan adalah lebih tinggi semasa tempoh bukan monsun manakala bagi musim monsun, ketam betina adalah lebih tinggi. Kesimpulannya, ekologi pemakanan ketam ladam bakau adalah lebih serupa dengan konspisifikasi yang dekat dan jauh spesis tersebut. Walau bagaimanapun, adalah didalilkan bahawa keutamaan yang lebih tinggi terhadap cacing polichaete oleh C. rotundicauda betina semasa puncak musim mengawan menunjukkan peranannya dalam mengawal kelakuan bersarang spesis ini.

Kata kunci: Carcinoscorpius rotundicauda; indeks elektiviti; indeks gastro somatik; ketam ladam bakau

RUJUKAN

Akbar John, B., Kamaruzzaman, B.Y., Jalal, K.C.A. & Zaleha, K. 2011. Study on the Bionomics of Malaysian horseshoe crabs Tachypleus gigas. International Symposium on Marine Ecosystems, Natural Products and Their Bioactive Metabolites.25 - 27 October, Bogor - Indonesia. p.137.

Alexander, S.A., Hobson, K.A., Gratto-Trevor, C.L. & Diamond, A.W. 1996. Conventional and isotopic determinations of shorebird diets at an inland stopover: the importance of invertebrates and Potamogeton pectinatus tubers. Can. J. Zool. 74: 1057-1068.

Botton, M.L. & Haskin, H.K. 1984. Distribution and feeding of the horseshoe crab, Limulus polyphemus, on the continental shelf of New Jersey. Fish. Bull. 82(2): 383-389.

Botton, M.L. 1984a. The importance of predation by horseshoe crabs, Limulus polyphemus, to an intertidal sand flat community. J. Mar. Res. 42(1): 139-162.

Botton, M.L. 1984b. Diet and food preference of the adult horseshoe crab, Limulus polyphemus in Delaware Bay, New Jersey, USA. Mar. Biol. 81: 199-207

Botton, M.L. & Shuster, C.N. 2004. Horseshoe Crabs in a Food Web: Who Eats Whom? In The American Horseshoe Crab, edited by C. N Shuster, R. B. Barlow & H. J. Brockmann, (eds.) Cambridge: Harvard Press.

Chatterji, A., Mishra, J. & Parulekar, A., 1992. Feeding behaviour and food selection in the horseshoe crab, Tachypleus gigas; (Müller). Hydrobiol. 246: 41-48.

Chatterji, A., Siddiqui, A.Q. & Khan, A.A. 1977. Food and feeding habits of Labeo gonius (Ham.) from the river Kali. J. Bombay Nat Hist. Soc. 75: 104-109.

Debnath, R. 1985. Studies on the distribution, abundance, breeding behaviour and feeding habit of Indian horseshoe crabs (Merostomata: Xiphosura) in the coastal water of Orissa and West Bengal, India. M. Phil. Diss. University of Calcutta, Calcutta.

Debnath, R. & Choudhury, A. 1987. Studies on food preference and feeding habit of horseshoe crabs (Merostomata: Xiphosura) in the coastal waters of West Bengal, India, Internatial Symposium on Tropical Ecology Banaras Hindu Unit, Varanasi, India

Gurr, E. 1965. The Rational Use of Dyes in Biology. Williams and Wilkins.

John, B.A., Jalal, K.C.A., Kamaruzzaman, Y.B. & Zaleha, K. 2010. Mechanism in the clot formation of horseshoe crab blood during bacterial endotoxin invasion. J. App. Sci. 10: 1930-1936.

Kamaruzzaman, B.Y., Akbar John, Jalal, K.C.A., Zaleha, K. 2011c.The Living Fossil (Horseshoe crab). Kuala Lumpur: IIUM Publisher.

Kamaruzzaman, B.Y., Akbar John, B., Aqilah Megat, M.H. & Zaleha, K. 2011b. Bioaccumulation of heavy metals in Horseshoe crabs (Tachypleus gigas) from Pekan, Pahang, Malaysia. Res. J. Environ. Toxicol. 5 (3): 222-228.

Kamaruzzaman, B.Y., John, B.A., Zaleha, K. & Jalal, K.C.A. 2011a. Molecular phylogeny of horseshoe crab. Asian J. Biotechnol. 3: 302-309.

Kassim, Z., Shahuddin, H., Shaharom, F. & Chatterji, A. 2008. Abundance of three species of the horseshoe crab along the coast of Malaysia. J. Bombay Nat. History Soc. 105: 209-211.

Lee, S.Y. 2008. Mangrove macrobenthos: Assemblages, services and linkages. J. Sea Res. 59(1-2): 16-29.

Lockwood, S. 1970. The horseshoe crab. American Narualist. 4:257-274.

Mishra, A. & Choudhury, A. 1985. Polychaetes annalids from the mangrove swamps of Sundarbans, India. Proceedings on the National Symposium on Biological Utilization and Conservation of Mangroves pp. 448–452.

Novitsky, T.J. 1982. Limulus amoebocyte lysate: Live saving extract from horseshoe crab. J. New England Aquarium (A quasphere) 16: 26-31

Novitsky, T.J. 1984. Discovery to commercialization: The blood of the horseshoe crab. Oceanus 27(1): 13-18

Samidurai, K., Saravanakumar, A. & Kathiresan, K. 2011. Spatial and temporal distribution of macrobenthos in different mangrove ecosystems of Tamil Nadu Coast, India. Environ. Monitor Assessment pp. 1-18.

Sekiguchi, K. 1988. Biology of Horseshoe Crabs. Tokyo: Science House Co., Ltd.

Sekiguchi, K. & Shuster, C.N. 2009. Limits on the Global Disrribution of Horseshoe Crabs (Limulacea): Lessons Learned from Two Lifetimes of Observations: Asia and America. In Biology and Conservation of Horseshoe Crabs, edited by Tanacredi, J.T., Botton, M.L., Smith, D.R., Earle, S.A. Springer US pp. 5-24.

Shuster, C.N., Jr. 1982. A pictorial review of the natural history and ecology of the horseshoe crab, Limulus polyphemus, with reference to other Limulidae. In Physiology and Biology of Horseshoe Crabs: Studies on Normal and Environmentally Stressed Animals, edited by J. Bonaventura, C. Bonaventura, and S. Tesh New York: Alan R. Liss, Inc.

Squires, H. & Dawe, E. 2003. Stomach Contents of Snow Crab (Chionoecetes opilio, Decapoda, Brachyura) from the Northeast New found land Shelf. J. Northw. Atl. Fish. Sci. 32: 27-38.

Suzuki, K., Shiho, O., & Imahori, K. 1975. Fructose-diphophate Aldolase of Horseshoe Crab (Tachypleus tridentatus). J. Biochem. 77(2): 281-289.

Uys, W., Hecht, T. & Walters, M. 1987. Changes in digestive enzyme activities of Clarias gariepinus (Pisces: Clariidae) after feeding. Aquaculture 63(1-4): 243-250.

Yamasaki, T., Makioka, T., Saito, J. 1988. Morphology. In Biology Of Horseshoe Crabs, edited by K. Sekiguchi. Tokyo: Science House.

Zaleha, K., Kamaruzzaman, B.Y., John, B.A. & Ong, M.C. 2010. Cd, Cu and Pb Concentration Levels in Horseshoe Crab Nesting Grounds of Pahang Coast, Malaysia. J. Biol. Sci. 10: 790-794.

*Pengarang untuk surat-menyurat; email: kama@iium.edu.my