EXPLOITATION STATUS AND FOOD PREFERENCE OF ADULT TROPICAL HORSESHOE CRAB, Tachypleus gigas BY MOHD RAZALI BIN MD RAZAK A thesis submitted in fulfilment of the requirement for the degree of Master of Science (Biosciences) Kulliyyah of Science International Islamic University Malaysia SEPT 2018 ABSTRACT According to this study, local in Malacca more preferred to apply the modern method (fishing net) (65.85%) than traditional method (hand-harvest) (34.15%) to harvest the T. gigas from the wild (p<0.05), while locals in Pahang more preferred to apply traditional (56.1%) than modern method (43.9%). Frequency of the modern harvesting method application in Malacca (25 ± 10.48 times) was higher than the traditional method (2 ± 0.73 times) and also higher compared to the modern method application in Pahang (6 ± 3.45 times) (p<0.05). Quantity of harvested crabs per month for one individual was higher in Malacca (16,860 T. gigas) compared to Pahang (4,180 T. gigas). Foods conditions would substantially influence their edibility. However, horseshoe crabs might have specific behaviour to manipulate the edibility of the foraged food. A total of 30 males and 30 females were introduced with five different natural potential feeds, namely, gastropods (Turritella sp.), crustacean (Squilla sp.), fish (Lates calcarifer), bivalve (Meretrix meretrix) and polychaete (Nereis sp.). The conditions of introduced feeds had been manipulated based on the natural foods condition in nature; decayed and protected in shell, hardened outer skin and host-tubed. Female crabs took shorter response period (3.42 ± 2.42 min) toward surrounding food compared to males (13.14 ± 6.21 min). Horseshoe crabs showed preference toward unshelled gastropods. The preference percentage of female (50%) toward unshelled gastropods was higher than males (36.67%). There is no preference behaviour showed by T. gigas on the shelled, hardened outer skin and host-tubed feed. Only the female crabs showed rejection toward decayed food. Different population of horseshoe crabs might have different food preferences. Stomach contents analyses were conducted on 60 samples of male and female; 10 males and 10 females were trapped in fishing net during the incoming high tide and 20 males and 20 females were hand-harvested at the spawning beach (10 samples during pre-mating and 10 during post-mating). This study found that echinoderm served as a main food composition in the gut of males (50%) and females (51.94%) during the open sea migration phase. The main composition was substituted by macrophyte (males: 59.51% to 65.15%; females: 36.36% to 58.10%) as they arrived to the spawning area. Based on Electivity Index, male crabs showed positive preference toward polychaete (EI: 0.04) and macrophyte (EI: 0.19) at the spawning site while, the females showed positive preference toward bivalve (EI: 0.46). In this study, 30 males and 30 females were introduced with gastropod, crustacean and bivalve in different percentage (0.2%, 0.6%, 1.0%, 1.4%, 1.8%, and 2.2%) that expressed from horseshoe crabs body mass to determine the level of the satiation. After being harvested from the wild, male crabs did not significantly eat until two weeks in captivity while, females (51.43% ± 25.54) started to eat during the early first week. Two-way ANOVA study found that females T. gigas’ satiation levels (crustacean: 1.7% ± 0.08; bivalve: 1.8% ± 0.06; gastropods: 1.8% ± 0.04) were significantly higher than males (crustacean: 1.4% ± 0.02; bivalve: 1.6% ± 0.05; gastropods: 1.7% ± 0.08) for all feed types (F = 13.98, p<0.05). Gut transit times of males (crustacean: 17 ± 1.7 hrs; bivalve: 17 ± 1.7 hrs; gastropods: 23 ± 4.6 hrs) were significantly longer than females (crustacean: 10 hrs ± 1.7; bivalve: 12 hrs ± 0; gastropods: 19 hrs ± 1.7)(F = 3.72, p<0.05). Male crabs took shorter time (1 ± 0 hr) to achieve their satiation compared to female crabs (2 ± 0 hrs). ii خﻻصة البحث ABSTRACT IN ARABIC إْ اٌص١ادْٚ اٌّحٛ١ٍْ فٚ ٟﻻ٠ت ِﻻوا، ٚفماً ٌٙزٖ اٌذساصت، ٠فضً اصخؼّاي اٌطش٠مت اٌحذ٠زت، أٞ اٌص١ذ باٌشبىت )ٍٝػ )٪98.;8 اٌطش٠مت ا١ٌذ٠ٚت اٌخم١ٍذ٠ت )67.48٪( ﻻصط١اد صشطاْ حذٚة اٌحصاْ )Tachypleus gigas( ِٓ اٌبحش )p<0.05(، ب١ّٕا ٠فضً اٌص١ادْٚ اٌّحٛ١ٍْ فٚ ٟﻻ٠ت با٘أغ اصخؼّاي اٌطش٠مت اٌخم١ٍذ٠ت )ٍٝػ )٪89.4 اٌطش٠مت اٌحذ٠زت )>.76٪(. واْ حىشاس اصخؼّاي طش٠مت اٌص١ذ اٌحذ٠زت فٟ ِﻻوا )58±;44.7 ِشة( أٍٝػ ِٓ اٌطش٠مت اٌخم١ٍذ٠ت )5±6:.4 ِشة( ٚوأج أٍٝػ وزٌه فٚ ٟﻻ٠ت با٘أغ ِماسٔت باٌطش٠مت اٌحذ٠زت )9±6.78 ِشة( )p<0.05(. وأج و١ّت صشطأاث حذٚة اٌحصاْ اٌّصطادة شٙش٠ا ٌٍفشد اٌٛاحذ أٍٝػ فٚ ٟﻻ٠ت ِﻻوا )94;،49 صشطأا( ِماسٔت بخٍه فٚ ٟﻻ٠ت با٘أغ )4;7،4 صشطأا(. حؤرش اٌظشٚف اٌغزائ١ت بشىً وب١ش ٍٝػ صﻻح١ت اٌضشطأاث ٌﻻصخٙﻻن، ِٚغ رٌه لذ ٠ىْٛ ٌذٜ صشطاْ حذٚة اٌحصاْ صٍٛن ِحذد ٌٍخﻻػب فٟ ِذٜ صﻻح١ت اٌغزاء اٌّجّّغ. حُ حمذ٠ُ خّش أغز٠ت طب١ؼ١ت ِخخٍفت إٌٝ 64 ِٓ روٛس اٌضشطاْ 64ٚ ِٓ اﻹٔاد. اﻷغز٠ت وأج= بط١ٕاث اﻷلذاَ ).ٚ ،)Turritella spاٌمشش٠اث ).ٚ ،)Squilla spاﻷصّان (ٚ ،(Lates calcariferرٚاث اٌصذفخ١ٓ (ٚ ،(Meretrix meretrixوز١شاث اﻷشؼاس ).Nereis sp(. حُ حمذ٠ُ اﻷغز٠ت اٌّمذِت ٍٝػ حضب طبؼ١ت اﻷغز٠ت فٟ اٌطبؼ١ت؛ ِزً حٍه اٌّخؼفٕت، ٚاٌّصذّفت، ٚاٌضاوٕاث فٟ اﻷٔاب١ب، ٚحٍه بجٍذ خاسجٟ لاس. أخزث إٔاد اٌضشطاْ فخشة اصخجابت ألصش )6.75±5.75 دل١مت( حجاٖ اﻷغز٠ت اٌّح١طت ِماسٔت باٌزوٛس )46.47±9.54 دل١مت(. أظٙشث صشطأاث حذٚة اٌحصاْ حفضٍٙ١ا ٌبط١ٕاث اﻷلذاَ ػذ٠ّت اﻷصذاف، ح١ذ وأج ٔضبت حفض١ً اﻹٔاد )84٪( ٌبط١ٕاث اﻷلذاَ ػذ٠ّت اﻷصذاف أٍٝػ ِٓ اٌزوٛس ):69.9٪(. ٌُ ٠ىٓ ٕ٘ان أٞ صٍٛن حفضٍٟ١ ِٓ صشطأاث حذٚة اٌحصاْ حجاٖ اﻷغز٠ت اٌّصذّفت، ٚاٌضاوٕاث فٟ اﻷٔاب١ب، ٚحٍه بجٍذ خاسجٟ لاس. سفضج إٔاد اٌضشطأاث فمط اﻷغز٠ت اٌّخؼفٕت. ٌٚزٌه لذ ٠ىْٛ ٌٍّجػّٛاث اٌّخخٍفت ِٓ صشطأاث حذٚة اٌحصاْ حفض١ﻻث غزائ١ت ِخخٍفت. أجش٠ج ححا١ًٌ ٌّحخ٠ٛاث اؼٌّذة ١ػ 94 ٍٝػٕت ِٓ اٌزوٛس ٚاﻹٔاد، ح١ذ حُ ص١ذ 44 روٛس ٚ 44 إٔاد بشبان اٌص١ذ خﻻي اٌّذ اؼٌاٌٟ اٌّٛاجٗ، ٚحُ ص١ذ 54 ِٓ اٌزوٛس ٚ 54 ِٓ اﻹٔاد فٟ شاطٝء ٚضغ اٌبٛ١ض ١ػ 44ٕاث خﻻي فخشة ِا لبً اٌخىارش ١ػ 44ٕٚاث أرٕاء اٌخىارش(. ٚجذث ٘زٖ اٌذساصت أْ شٛو١اث اٌجٍذ وأج اٌّىْٛ اٌغزائٟ اٌشئ١ضٟ فٟ أؼِاء اٌزوٛس )ٚ )٪84اﻹٔاد )7>.84٪( خﻻي ِشحٍت اٌٙجشة فٟ اٌبحش اٌّفخٛح، ٚبؼذ٘ا أصبحج إٌباحاث اٌّائ١ت اٌّىْٛ اٌشئ١ضٟ )اٌزوٛس= 8.>8٪ إٚ ، ٪98.4 ٌٝاﻹٔاد= 69.6٪ إػ )٪8;.44 ٌٕٝذ ٚصٛي اٌضشطأاث إٌٝ ِٕطمت ٚضغ اٌبٛ١ض. اصخٕاداً إٌٝ ِؤشش اﻻخخ١اس، أظٙش اٌزوٛس حفض١ﻻ ٚصٍٛوا إ٠جاب١ا حجاٖ ِخؼذداث اﻷشٛان )ٚ )4.4<=EIإٌباحاث اٌّائ١ت )EI=4.79( فِٛ ٟلغ ٚضغ اٌبٛ١ض، فٟ ح١ٓ أظٙشث اﻹٔاد حفض١ًٍا صٍٛوا إ٠جاب١ًا حجاٖ رٚاث اٌضذفخ١ٓ )EI=>4.4(. حُ فٟ ٘زٖ اٌذساصت حمذ٠ُ بط١ٕاث اﻷلذاَ، ٚاٌمشش٠اث، ٚرٚاث اٌصذفخ١ٓ إٌٝ 64 ِٓ اٌزوٛس 64ٚ ِٓ اﻹٔاد بٕضب ِخخٍفت )٪4.5، 5.5ٚ ،٪4.;ٚ ،٪4.7ٚ ،٪4.4ٚ ،٪4.9ٚ٪( اٌخٟ حُ اشخمالٙا ِٓ وخً أجضاَ صشطأاث حذٚة اٌحصاْ ٌخحذ٠ذ ِضخٜٛ اٌشبغ. بؼذ اﻻصط١اد ِٓ اٌبحش، ٌُ ٠أوً روٛس اٌضشطاْ بشىً ٍِحٛظ حخٝ أصب١ػٛٓ فٟ اٌحجز، ب١ّٕا بذأث اﻹٔاد )84.76٪ ± 58.87( بخٕاٚي اٌطؼاَ خﻻي اٌفخشة اٌّبىشة ِٓ اﻷصبٛع اﻷٚي. ٚجذث دساصت ANOVA اﻹحصائ١ت راث اﻻحجا١٘ٓ أْ ِضخ٠ٛاث شبغ إٔاد صشطأاث حذٚة اٌحصاْ )لشش٠اث= :.4٪ ± ;4.4؛ ٚرٚاث اٌصذفخ١ٓ= ;.4% ± 0.06؛ ٚبط١ٕاث اﻷلذاَ= ;.4٪ ± 4.47( وأج أٍٝػ بشىً ٍِحٛظ ِٓ اٌزوٛس )لشش٠اث= 4.7٪ ± 4.45؛ ٚرٚاث اٌصذفخ١ٓ= 4.9% ± 4.48؛ ٚبط١ٕاث اﻷلذاَ= :.4٪ ± ;4.4( ٌج١ّغ أٛٔاع اﻷغز٠ت )p<0.05 ،13.98 =F(. أٚلاث ػبٛس اٌمٕاة اٌٙض١ّت ٌٍزوٛس )اٌمشش٠اث= :4 ± :.4 صاػت؛ رٚاث اٌمششح١ٓ= :4 ± :.4 صاػت ؛ بط١ٕاث اﻷلذاَ= 56 ± 7.9 صاػت( وأج أطٛي بىز١ش ِٓ اﻹٔاد )اٌمشش٠اث= 44 ± :.4 صاػت؛ رٚاث اٌصذفخ١ٓ= 45 ± 4 صاػت؛ بط١ٕاث اﻷلذاَ >4 ± :.4 صاػت( )p<0.05 ،3.72 =F(، ٚاصخغشق اٌزوٛس ٚلخا ألصش )4 ± 4 صاػت( ٌخحم١ك شبٙؼا ِماسٔت باﻹٔاد )5 ± 4 صاػت(. iii APPROVAL PAGE I certify that I have supervised and read this study and that in my opinion; it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a thesis for the degree of Master of Science (Biosciences). ………………………………….. Zaleha binti Kassim Supervisor ………………………………….. Mohd Armi bin Abu Samah Co-Supervisor ………………………………….. Asnor Azrin bin Sabuti Co-Supervisor I certify that I have read this study and that in my opinion; it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a thesis for the degree of Master of Science (Biosciences). ………………………………….. Mohammad Mustafizur Rahman Internal Examiner ………………………………….. Samsur bin Mohamad External Examiner This thesis was submitted to the Department of Biotechnology and is accepted as a fulfilment of the requirement for the degree of Master of Science (Biosciences). ………………………………….. Mardiana binti Mohd Ashaari Head, Department of Biotecnology This thesis was submitted to the Kulliyyah of Science and is accepted as a fulfilment of the requirement for the degree of Master of Science (Biosciences). ………………………………….. Shafida binti Abd Hamid Dean, Kulliyyah of Science iv DECLARATION I hereby declare that this thesis is the result of my own investigations, except where otherwise stated. I also declare that it has not been previously or concurrently submitted as a whole for any other degrees at IIUM or other institutions. Mohd Razali Bin Md Razak Signature ........................................................... Date ......................................... v COPYRIGHT PAGE INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA DECLARATION OF COPYRIGHT AND AFFIRMATION OF FAIR USE OF UNPUBLISHED RESEARCH EXPLOITATION STATUS AND FOOD PREFERENCE OF ADULT TROPICAL HORSESHOE CRAB, Tachypleus gigas I declare that the copyright holders of this thesis are jointly owned by the student and IIUM. Copyright © 2017 Mohd Razali bin Md Razak and International Islamic University Malaysia. All rights reserved. No part of this unpublished research may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without prior written permission of the copyright holder except as provided below 1. Any material contained in or derived from this unpublished research may be used by others in their writing with due acknowledgement.