Coral Reef Sea Cucumbers In Malaysia - IIUM Repository (IRep)

Malaysian Journal of Science 28 (2): 171– 186 (2009)Tanjung Gemuk beach on 5th April 2005 aboutthree months after the big tsunami incident on 26thDecember 2004 has opened the eyes ofMalaysians about the possible environmentalthreatens to indigenous sea cucumbers. However,until now there is still no strong experimental testexplaining the real causes of such phenomenon.shared the same percentage of 12.5% (i.e. onespecies each). The above studies were done onSabah coral reef habitats. Besides, [8] reported theexistence of 23 species of sea cucumbers observedat few locations in Peninsular Malaysia with sixundetermined species yet to be identified.Furthermore, [9] described 37 species of seacucumbers from Peninsular Malaysia and Sabahwith six species requires further speciesidentification. In Pulau Besar, Johor Darul Takzim[10] observed three genera and seven species ofsea cucumbers with four species from the genusStichopus yet to be identified, and Stichopus wasconsidered as the most dominant genus. [11]Subsequently published the documentation of ninespecies of order Dendrochirotida from the NorthWest Coast of Borneo and Peninsular Malaysia.Accordingly, the general objective of this study isto document species presence and distribution ofsea cucumbers on several coral reef habitats ofMalaysia, covering Peninsular Malaysia, WestMalaysia and Sabah, East Malaysia. Findingsfrom previous studies on sea cucumbers inMalaysia were used as comparison to theoutcomes from this study. Topics on the speciespresence, distribution and issues related to theecology and economic aspects were correlated anddiscussed. The outputs from this present study areforeseen to be main guideline in future research inMalaysia, especially for studies involvingmolecular techniques as additional approaches.The species validation of Stichopus hermanni toStichopus horrens was highlighted by Zulfigarat.el [12] mentioning that the specimen that wasthought to be Stichopus variegatus for long timein Malaysia is actually Stichopus horrens, basedon its colour variation and body wall patterns.Stichopus variegatus was the old name forStichopus hermanni. Apart from that, furtherefforts had been carried out to verify and validatethe taxonomic status of sea cucumbers inMalaysia, e.g. an effort taken by Massin at.el [13]in describing two new species from genusStichopus found at the Johor Marine Park, JohorDarul Takzim, Malaysia - S. ocellatus n. sp. and S.rubermaculosus n. sp. Moreover, a report on thespecies presence and distribution of seacucumbers in Malaysia by Kamarul and Ridzwan[14] had indicated that a large number ofundetermined species of sea cucumbers (i.e. 19undetermined species out of total 39 speciesrecorded) were present in Sabah. They also foundthat southern part of Sabah, i.e. Semporna showedthe highest diversity of sea cucumbers, and theyspeculated that the proximity of Sabah to theWallace’s Line may be one of the factorscontributing to the high diversity. The abovestudies indirectly suggested and revealed theunclear and problematic taxonomic status of seacucumbers particularly in Malaysia, based on thedocumentation of a large number of undeterminedspecies. In views of environmental concern, thesudden appearance of a large number of brunokfrom order Molpadiida along few main beachareas in Port Dickson, Negeri Sembilan includingMATERIALS AND METHODSStudy SitesSea cucumbers from several coral reef habitats inPeninsular Malaysia, West Malaysia and Sabah,East Malaysia (Figure 1) were observed,photographed and sometimes collected withofficial permission. The samplings took place forapproximately 3 years, from August 2004 untilOctober 2007. The study sites were on intertidalzone, and most documentation was done duringthe low tide. No fixed or standard sampling hourswere allocated for all sites. Within PeninsularMalaysia, coral reef habitats of Pangkor Island,Perak Darul Ridzuan; Tanjung Gemuk, NegeriSembilan Darul Khusus and surrounding islandsin Langkawi, Kedah Darul Aman were chosen asstudy sites in the West Coast region. The studysites in the East Coast region were Kapas Island,Perhentian Island and Redang Island inTerengganu Darul Iman; and Tioman Island inPahang Darul Makmur. Two main study siteswere selected in Sabah i.e. Kota Kinabalu andTuaran in the northern part and Semporna in thesouthern part. Global Positioning System (GPS)was used to mark and to record the position ofeach sampling site (not shown specifically, referto Figure 1).173

Malaysian Journal of Science 28 (2): 171– 186 (2009)Figure 1. Study area with the 10 main sampling sites (with numbers).RESULTSSampling and Species IdentificationSea cucumbers were sampled with the assistanceof professional divers and local residents. Speciesidentification of sea cucumbers by morphologywas done by referring to the previous studies,supporting references and also through theinformationgivenbylocalresidents.Undetermined species are designated temporarilyas sp. (e.g. Stichopus sp.4; Table 1) with providedlocal names. Photographs were also taken asbackup and further references.As many as 50 species of sea cucumbers werefound to date in several coral reef habitats ofPeninsular Malaysia, West Malaysia and Sabah,East Malaysia (Table 1) with 34 species (Table 2)require further species identification. Of the totalnumber of species, 18 species (i.e. 36%) recordedwere from genus Holothuria, indicating thehighest percentage of species diversity;subsequently followed by genus Actinopyga with15 species (i.e. 30%), and genus Stichopus withnine species (i.e. 18%). Percentage of 8% (i.e.four species) was shown by genus Bohadschia and4% (i.e. two species) by genus Synapta. Thelowest percentage of diversity was shared bygenera of Molpadia and Pearsonothuria with 2%each (i.e. one species each).Storage and PreservationFor short-term storage, fresh specimens of deadsea cucumbers were stored in ice boxes containingice cubes or seawater during sampling. In thelaboratories, specimens were transferred into 20oC fridge or -80oC freezer for long-term storage.Specimens are also preserved in 70% ethanol,with proper cataloging.The present study showed that 10 species wereobtainable from both Peninsular Malaysia andSabah. In terms of undetermined species, 14174

Malaysian Journal of Science 28 (2): 171– 186 (2009)species sampled were from genus Actinopyga,nine species from genus Holothuria, six speciesfrom genus Stichopus, two species from genera ofBohadschia and Synapta; and one species fromgenus Molpadia (Table 2). Interestingly, 13undetermined Actinopyga species were foundaround coral reef habitats of Binawan Island,Semporna and one undetermined species wasrecorded in Redang Island, Terengganu DarulIman, East Coast of Peninsular Malaysia. All the34 undetermined species greatly need furtherverification based on ossicle characters, behaviourand molecular phylogeny. It is foreseen that asmall number of the undetermined species,especially among Actinopyga species observed inSabah, are new species. With respect tobiogeography, the proximity of Sabah region tothe Wallace’s line may contribute to such possiblephenomenon.progressive with the continuous and consecutiveattempts by local scientists and outsiders. Thetaxonomic revision has become more challengingwith the current findings of 34 undeterminedspecies in Malaysia, as well as the previousfindings [5], [8], [10] and [13]. In spite of that, thepresent study along with previous research arelikely manageable to provide up-to-date view ofspecies presence and distribution of seacucumbers in Malaysia, making such update thehead start for subsequent future research,particularly in using molecular approaches torevise the taxonomic validity. In fact, organismgroups with well-known taxonomies are importantto ease the difficulties in listing existing species ina population [15].In total, three orders of sea cucumbers werecurrently found in Malaysia i.e. Aspidochirotida,Molpadiida and Apodida; with seven genera and50 species distributed among the orders. Thepresent findings showed high diversity of seacucumber in Malaysia. The total number ofspecies recorded is higher than the records by [9],whereby they described 37 species with sixspecies requiring further species identification.The presence of other species had also beenrecorded previously, [11] recorded the presence ofnine species from order Dendrochirotida from theNorth West Coast of Borneo and PeninsularMalaysia. Furthermore, Colochirus robustus (thesynonym of Colochirus luteus) was likely to be acommon species around the Bodgaya Islands inSabah, East Malaysia [16]. Apart from that, [8]recorded the presence of other species in Malaysiasuch as Thelenota ananas, Actinopyga echinites,Actinopyga miliaris, Synapta recta and Stichopushermanni (formerly known as Stichopusvariegatus). Some local residents also claimed thepresence of large conspicuous Thelenota anax andother Synaptids (e.g. Synapta maculata andEuapta godeffroyi) on Malaysian coral reefhabitats. Besides, Siti et al. [10] documented threegenera and seven species of sea cucumber inBesar Island, Johor Darul Takzim with fourspecies from the genus Stichopus yet to beidentified. As the species identification becamecomplicated, further effort had been taken byMassin et al. [13] in describing two new speciesfrom genus Stichopus found at the Johor MarinePark, Johor Darul Takzim, Malaysia - Stichopusocellatus n. sp. and Stichopus rubermaculosus n.In the West Coast of Peninsular Malaysia, lowlevel of sea cucumber diversity was measuredaround the coral reef habitats of Pangkor Island,Perak Darul Ridzuan and surrounding islands inLangkawi, Kedah Darul Aman. Only three species- Holothuria leucospilota, Holothuria atra and bathati or brunok from order Molpadiida - wereobserved in Langkawi after two surveys, e.g.around Selat Bagan Pauh, Tanjung Pandan andIntan Besar Island (previously known as KentutBesar Island); while only Stichopus horrens andHolothuria leucospilota were documented oncoral reef habitats of Teluk Nipah and PasirBogak, Pangkor. However, the individual numberof Stichopus horrens was recorded high aroundTeluk Cina, Pasir Bogak in Pangkor. In contrast,coral reef habitats of the East Coast, for instancein Terengganu Darul Iman, indicated higherdiversity level of sea cucumber (i.e. 11 species),including the findings of eight undeterminedspecies. Furthermore, higher diversity level of seacucumbers was also shown by Tioman Island,Pahang Darul Makmur. Tioman Island indicatedthe existence of 15 species of sea cucumbersincluding seven undetermined species requiringfurther species identification.DISCUSSIONGenerally, the process of establishing taxonomicupdate for sea cucumbers (Echinodermata:Holothuroidea) in Malaysia was challenging but175

Malaysian Journal of Science 28 (2): 171– 186 (2009)sp. Accordingly, it is estimated that more than 80species of sea cucumbers are present in Malaysia.Relatively, the number of Actinopyga speciescurrently recorded was larger in comparison withthe overall findings by [5], [8] and [9].Furthermore, [8] recorded the existence of twoSynapta species (i.e. Synapta recta and Synaptasp.1) in Tioman Island and Payar Island,Langkawi. These showed that Synaptids were alsopresent in both Peninsular Malaysia and Sabah.On top of that, proper management of marine parkzone, e.g. Tunku Abdul Rahman Park, KotaKinabalu may have also contributed to the greatspecies richness in Sabah. Recreational zone andreserve zone are being implemented in coral reefhabitat of Manukan Island, Kota Kinabalu, Sabahfor instance in order to ensure that the gene pool isretained while the eco-tourism is developing.However, some issues brought by [18] pertainingto the lack of manpower in Sabah FisheriesDepartment and weak monitoring proceduresrequire great concern and immediate action indeveloping a workable strategy towardsmanagement of sea cucumber fisheries.In the present study, the greatest diversity of seacucumbers was shown by order Aspidochirotida.This finding is supported by Ridzwan [5] andBaine [8] who identified five genera of orderAspidochirotida namely Holothuria, Stichopus,Thelenota, Bohadschia and Actinopyga - makingthis order the most abundant and in the front rankof top species diversity within Malaysian coralreef habitats. As there are many previous researchand personal comments showing the presence ofother species such as Thelenota anax, Thelenotaananas, Stichopus hermanni, and species fromorder Dendrochirotida [11] that were not recordedin the present study, further research especially onmolecular approaches and more study sitesincluding Sarawak, East Malaysia need to beincluded in the future. Recent developments inDNA research could ease the difficulties inidentifying closely related species whentraditional characters have been proveninconclusive [1]. In general, current speciesabundance of sea cucumbers in Malaysia hasdisplayed patchiness, even if it was relatively highin few study sites.With respect to biogeography, the proximity ofSabah region to the Wallace’s line may alsocontribute to the high level of species presenceand distribution of sea cucumbers on Sabah coralreef habitats. It is postulated that sea cucumberspecies from both Oriental and Australian regionsmay have mingled within the Wallace’s line,causing the high species diversity within Sabahcoral reef habitats. However, the existing data arestill considered inadequate and further studies aregreatly needed in the future for better view andconfirmation. It is further postulated that theconnection of Peninsular Malaysia to Sabah, EastMalaysia by Sunda Shelf during the Pleistocenemaximum lowering of seawater [19] has led to therelatively high difference of species diversitybetween the two regions, as indicated mainly byspecies from genus Actinopyga.In Sabah, East Malaysia comprising Bodgaya andLigitan groups of islands, the coral reef formationis well-developed in seawater region of SulawesiSea [17]. Coral reef area in tropical region is thebest habitat for sea cucumbers due to the abundantsource of organic particles as food [5]. Bothstatements are in congruence with the currentfindings of diverse species of sea cucumbers oncoral reef habitats of Semporna, Sabah e.g. inMaiga Island (part of Bodgaya group) and MabulIsland (part of Ligitan group). Such uniquenessand privilege have made Sabah the mostsignificant state in Malaysia for sea cucumberfisheries, with the dominant product fromprocessing is beche-de-mer. Around 155 tonnes ofsea cucumbers were landed in 1995 as estimatedby the Sabah Fisheries Department, by which awide variety of species are targeted mainly forfood industry of beche-de-mer in Sabah. Thecurrent observation of 37 species inclusive of 13undetermined Actinopyga species in Sabah alsoindicated that Sabah in general and Semporna inparticular had the best and the most interestingspecies diversity of sea cucumbers in Malaysia.There was no clear and up-to-date information onthe distribution of sea cucumbers in Sarawak, EastMalaysia. Biogeographically, Sarawak is situatedclose to the lowland centre of historic SundaPlatform. According to Ho S.L [20], the growth ofcoral reefs in seawater region of Sarawak, EastMalaysia e.g. coral reef habitats surroundingTalang-Talang Besar Island, Talang-TalangKechil Island, Sampadi Island, Satang BesarIsland and Satang Kechil Island were limited due176

Malaysian Journal of Science 28 (2): 171– 186 (2009)to the high turbidity and influx of fresh water fromthe rivers of Sarawak mainland. Thedevelopments in tourism as well as the proximityof surrounding islands to the mainland have alsoworsened the condition. Only the use of brunokfrom order Molpadiida as fishing bait amongSarawak residents was mentioned by Ridzwan [5].In Sabah, brunok is commonly known as bat hati(Table 1). In Brunei Darussalam, Lane [6]reported a wide diversity of sea cucumbers on thecoral reef habitats, whereby 14 species wereobserved. Holothuria atra, Holothuria edulis andspecies from genus Bohadschia were among thespecies present on Brunei Darussalam coral reefhabitats. However, it was mentioned that thesources of sea cucumbers in Brunei Darussalamare not fully explored and relatively unexploitedas compared to most Indo-Pacific reef habitats [7].Furthermore, Lane [6] also stated that two of thefour Bohadschia species in Brunei Darussalamwere considered new to science. This findingseems further strengthening the proposal that newspecies could be present on the coral reef habitatsof Borneo Island. As Brunei Darussalam issituated next to Sarawak and Sabah within theBorneo Island, it is foreseen that Sarawak mayhave the same or greater diversity of seacucumber, even if some observation [17] could bea major contribution to low species diversity.recorded high in this study around Pasir Bogak,Pangkor. As a result, Stichopus horrens hasbecome the major target by a fisher of PangkorIsland for gamat oil and gamat water, as stated by[18]. However, the latter statement is contrary toother findings [8] that mentioned the presence ofStichopus hermanni (previously accepted asStichopus variegatus) instead. There are also otherstatements mentioned by [8] contradicting with[18]. It is believed that [18] had made verificationand correction to the species identification by [8],as [21] further verified the findings from [18].Furthermore, [20] found that the distribution ofcoral reefs along the West Coast of PeninsularMalaysia was deemed poor and the underwatervisibility was not good; and these findings werelikely related to the low level of sea cucumberdiversity currently observed in the West Coastregion. Such statement was further supported by[18] referring to the regular importation of seacucumbers from Adang, Thailand during the1990s. Limited coral growth is believed to affectthe marine-living organisms such as seacucumbers that depend on the coral reefs as mainhabitat and food source. Likewise, the presentobservation also revealed the poor distribution ofcoral reefs on few coral reef habitats of PeninsularMalaysia, especially in Langkawi Island, possiblydue to the negative impacts originated fromanthropogenic threats. Direct exploitation,introduced species, extinction cascades, habitatloss and degradation are factors leading to speciesdeclines [22]. Hence, it is clear that coral reefdestruction is proportional to the reduction ofspecies richness and ecological diversity of seacucumbers. [9] found that Stichopus horrens wasrare at Langkawi Island, supporting the possibilityof declination in sea cucumber processing andtrade industry of the traditional fishery site. Inorder to help maintaining the stock for seacucumber trade in Langkawi, [18] suggested thatthe demand in Langkawi may be supplied fromthree directions: from within through restockinginitiatives, from Thailand in a trade agreement andfrom Pangkor Island, Perak Darul Ridzuan,Malaysia as part of a managed fishery.Interestingly, Payar Island within Langkawi groupshowed the presence of 10 species [8] thusmaking it the prospective study site in futurestudies.There are two main regions of coral reefs inPeninsular Malaysia - the East Coast and the WestCoast. In present study, the level of sea cucumberdiversity in the West Coast of Peninsular Malaysiawas considered low, due to the small number ofsea cucumber species currently observed inPangkor Island, Perak Darul Ridzuan; TanjungGemuk, Negeri Sembilan Darul Khusus andLangkawi Island, Kedah Darul Aman. Only fourspecies were documented - Stichopus horrens,Holothuria atra, Holothuria leucospilota and bathati from order Molpadiida. [8] showed thealmost similar records as from this present studyabout the species presence in Pangkor Island.However, local residents in Pangkor Islandclaimed that other species like Stichopuschloronotus,Thelenota ananas and anundetermined Stichopus species were also presenton the coral reef habitats of Pangkor Island, PerakDarul Ridzuan. Stichopus horrens was rare atLangkawi Island as supported by [9] but theindividual number of the same species was177

Malaysian Journal of Science 28 (2): 171– 186 (2009)Until nowadays, sea cucumbers are not includedin the list of endangered species in Malaysia,neither it is considered endangered by the WorldConservation Union (IUCN) which maintains aglobal list of endangered species. In terms of theconservation of sea cucumber in Malaysia, [23]emphasized the need to support the inclusion ofsea cucumber species from the families ofHolothuridae and Stichopodidae into theAppendices of the Convention on InternationalTrade in Endangered Species of Wild Fauna andFlora (CITES) as protected species. Theysuggested that few considerations must beaddressed and put into account before suchinclusion is made especially issues pertaining tolegislation and administration, the status of seacucumber as a protected species, and research intothe status and level of exploitation of seacucumber resources.in the front rank of top 12 megadiversity countriesin the world.SUMMARYIn summary, the present study showed thepresence of three orders of sea cucumber(Echinodermata: Holothuroidea) in Malaysiacomprising seven genera and 50 species. OrderAspidochirotida had shown the highest diversityof sea cucumbers (i.e. 47 species; 94%). Largenumber of diverse sea cucumber species wasrecorded in Sabah (i.e. 37 species) whilePeninsular Malaysia indicated the presence of 21species. Furthermore, 10 species were obtainablefrom both regions. Biogeographical factors mayhave influenced the high diversity of seacucumber observed on Sabah coral reef habitat

Several coral reef habitats in Peninsular Malaysia, West Malaysia and Sabah, East Malaysia were selected as study sites. In summary, the present data showed the presence of 50 species of sea cucumbers from three orders and seven genera, with 34 species require further species identification. .