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(a) Location map of the Wakatobi Marine National Park in S.E. Sulawesi, Indonesia. (b) Areas of study; Sampela, Kaledupa, Pak Kasim's and Ridge 1 off the islands Kaledupa and Hoga respectively.
Source publication
Ecological and taxonomic study of the coral associate serpulid polychaetes within the genus Spirobranchus, on coral reefs within the Wakatobi Marine National Park, SE Sulawesi, Indonesia.
Contexts in source publication
Context 1
... Wakatobi Marine National Park (formerly Tukang Besi Islands) is a remote island group of ca. 2000 km 2 in S.E. Sulawesi, Indonesia (Fig. 1a). Established in 1996, the Wakatobi MNP contains ca. 500 km 2 of the most biodiverse coral reefs in the world (Scaps & Denis 2007), with 396 scleractinian coral species, a low incidence of disease (0.57% see Haapkylä et al. 2007) and relatively free of recent ENSO-induced bleaching events (Crabbe & Smith, 2003) likely due to local ...
Context 2
... sites were selected around the islands Kaledupa (ca. 17,000 people) and Hoga (<100 people, Fig. 1b) relative to their variability in natural and anthropogenic impact, and recovery. Sampela, an enclosed lagoon with an outer reef wall ca. 400 m from a Bajau (sea gypsy) village of ca. 1300 people, is subject to continuous exploitation through coral mining, fishing activities, and high sediment loading due to natural re-suspension, ...
Context 3
... soft coral dominated reef flat due to extensive blast fishing ( Fox et al. 2003) until 2005. Pak Kasim's, ca. 500 m offshore, is an intermediate topographically complex fringing reef, subject to coral mining and blast fishing on the reef flat and crest until 2004. Ridge 1, ca. 1 km offshore, is an exposed reef ridge with strong water currents (Fig. 1b) and upwelling with nominal blast fishing on the reef crest in 2004. All sites have a pronounced reef flat (< 3 m), reef crest (3 -6 m) and slope (> 6 m) with varying levels of sedimentation draining from the reef flats during spring tides (Smith pers. comm. 2006). ...
Context 4
... characteristic of heavily disturbed or overfished sites ( Fox et al. 2003). Greater abundance of both overall live coral cover and S. giganteus at Kaledupa, however, is probably an artifact of elevated wave activity, low turbidity and reduced human impact at this site. High water motion and localized upwelling at Ridge 1 (Smith pers. comm. 2006, Fig. 1b) provides elevated nutrients for primary productivity, thus enhanced substrate and food availability (Jokiel 1978, Floros et al. 2005. Spirobranchus giganteus typically colonizes prominently positioned corals ( Strathmann et al. 1984, Hunte et al. 1990b, Martindale 1992, Dai & Yang 1995) in moderate-high wave exposure (Martindale 1992, ...
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Citations
... At the moment, genus Spirobranchus consists of 37 species and can be found in all coral reef regions in the world (Polychaeta 2021). Spirobranchus is considered a host generalist; the worms can live in almost all stony corals, including Scleractinia (anthozoan) and Hydrozoa (Millepora) (Rowley 2008;Hoeksema et al. 2020). Nevertheless, recent studies also reported that CTW could also live in various secondary hosts including mushroom coral, zoantharian, ascidian, octocorallia (soft coral), sponges, and live bivalve shells ten Hove 2014, 2017;van der Schoot et al. 2016;García-Hernández and Hoeksema 2017;Hoeksema et al. 2020). ...
... In this study, no CTW was found as a symbiont with staghorn coral Acropora sp. and other secondary hosts such as zoanthids, ascidians and soft corals. The absence of CTW on Acropora sp. is expected as other recent studies also exempting Acropora species among the list of CTW host (Song 2006;Rowley 2008;Perry et al. 2018) or recorded a very low number of individuals (Dai and Yang 1995). Interestingly, a high number of S. corniculatus larvae was recorded on live Acropora prolifera compared to other substrates (Marsden 1987). ...
... Also, the current around Bidong Island moves from north to south with the maximum speed of 0.22 m/s (Daud and Akhir 2015), which may reduce the opportunity for trochophore larvae of S. corniculatus to settle on a potential host at 8-10 m. Thus, the 'Goldilock' depth (5-7 m) for CTW to live is characterised by moderate wave action, lower water temperature compared to the shallow depth and less abrasive sediment presence with The outcome is slight contradict from a study done by Rowley (2008) in Indonesian reefs at Wakatobi Marine National Park, Indonesia. However, all sampling sites in the Indonesian study are located at the exposed fringing reefs subjected to high sedimentation, moderate-high wave action and strong current. ...
To understand the effect of lunar phase on nocturnal variation of zooplankton from coral-reef of Bidong Island, zooplankton was obtained during full moon (31th, August–3 September 2016) and new moon phases (17–20th September 2016) at three hour intervals for a 72 period. The zooplankton was hauled vertically with a Kitahara net (mesh size of 100 µm). The variation pattern of zooplankton density showed a significant nocturnal increase with the highest peak in abundance at 3 a.m and the lowest density observed at 3 p.m (p < 0.05). Overall zooplankton density was higher during the new moon compared with that of the full moon (p < 0.05). The density difference between lunar phases has significant difference (p < 0.01) during night-to-night comparison while no significant difference noted during day-to-day comparison which indicates variability during the night and suggesting lunar phase would likely induce such variation. In addition, the migration pattern of zooplankton is suggested to be driven by adult copepods which show significant differences in density between day and night (p < 0.05) due to their ability for strong active movement. Future research on the differences in zooplankton density at genus or species level at different depth depending on lunar light level and seasonal variation should be carried out to provide further insights on the mechanism of zooplankton migration occurring in Bidong Island.KeywordsDiel migrationFull and new moonNocturnalZooplanktonSouth China Sea
... At the moment, genus Spirobranchus consists of 37 species and can be found in all coral reef regions in the world (Polychaeta 2021). Spirobranchus is considered a host generalist; the worms can live in almost all stony corals, including Scleractinia (anthozoan) and Hydrozoa (Millepora) (Rowley 2008;Hoeksema et al. 2020). Nevertheless, recent studies also reported that CTW could also live in various secondary hosts including mushroom coral, zoantharian, ascidian, octocorallia (soft coral), sponges, and live bivalve shells ten Hove 2014, 2017;van der Schoot et al. 2016;García-Hernández and Hoeksema 2017;Hoeksema et al. 2020). ...
... In this study, no CTW was found as a symbiont with staghorn coral Acropora sp. and other secondary hosts such as zoanthids, ascidians and soft corals. The absence of CTW on Acropora sp. is expected as other recent studies also exempting Acropora species among the list of CTW host (Song 2006;Rowley 2008;Perry et al. 2018) or recorded a very low number of individuals (Dai and Yang 1995). Interestingly, a high number of S. corniculatus larvae was recorded on live Acropora prolifera compared to other substrates (Marsden 1987). ...
... Also, the current around Bidong Island moves from north to south with the maximum speed of 0.22 m/s (Daud and Akhir 2015), which may reduce the opportunity for trochophore larvae of S. corniculatus to settle on a potential host at 8-10 m. Thus, the 'Goldilock' depth (5-7 m) for CTW to live is characterised by moderate wave action, lower water temperature compared to the shallow depth and less abrasive sediment presence with The outcome is slight contradict from a study done by Rowley (2008) in Indonesian reefs at Wakatobi Marine National Park, Indonesia. However, all sampling sites in the Indonesian study are located at the exposed fringing reefs subjected to high sedimentation, moderate-high wave action and strong current. ...
This study provides a list of decapod crustacean families from Bidong Island retrieved from the collections of South China Sea Repository and Reference Centre (RRC), Institute of Oceanography and Environment. Three infraorders are present based on the collections, namely Anomura, Brachyura, and Caridea, and are constituted by 15 families. Based on the collections, the most abundant family within the infraorder Anomura is mainly composed of the porcelain crabs Porcellanidae (28%). Of the three infraorders, nine families were listed for the Brachyura (the true crabs) with the highest representation from the coral crabs Xanthidae (14%) and swimming crabs Portunidae (11%). Five families that were recorded for the infraorder Caridae, (caridean shrimps) based on dominance are Alpheidae, Pasiphaeidae, Thoridae, Palaemonidae, and Pandalidae. This infraorder of shrimp contains most of the commercial shrimp species from Family Palaemonidae and Pandalidae. This research is one of the many efforts to provide a baseline study for future identifications on decapods of Malaysia that can aid in future research with regards to conservation, population genetics, phylogenetics, biogeography and ecological understanding. This available inventory from RRC well serves as a platform for accessibility of specimens that has the perspective of being new species and new records, deeming it necessary for future investigations.KeywordsAnomuraBidong IslandFamilial checklistMalaysiaTerengganu
... At the moment, genus Spirobranchus consists of 37 species and can be found in all coral reef regions in the world (Polychaeta 2021). Spirobranchus is considered a host generalist; the worms can live in almost all stony corals, including Scleractinia (anthozoan) and Hydrozoa (Millepora) (Rowley 2008;Hoeksema et al. 2020). Nevertheless, recent studies also reported that CTW could also live in various secondary hosts including mushroom coral, zoantharian, ascidian, octocorallia (soft coral), sponges, and live bivalve shells ten Hove 2014, 2017;van der Schoot et al. 2016;García-Hernández and Hoeksema 2017;Hoeksema et al. 2020). ...
... In this study, no CTW was found as a symbiont with staghorn coral Acropora sp. and other secondary hosts such as zoanthids, ascidians and soft corals. The absence of CTW on Acropora sp. is expected as other recent studies also exempting Acropora species among the list of CTW host (Song 2006;Rowley 2008;Perry et al. 2018) or recorded a very low number of individuals (Dai and Yang 1995). Interestingly, a high number of S. corniculatus larvae was recorded on live Acropora prolifera compared to other substrates (Marsden 1987). ...
... Also, the current around Bidong Island moves from north to south with the maximum speed of 0.22 m/s (Daud and Akhir 2015), which may reduce the opportunity for trochophore larvae of S. corniculatus to settle on a potential host at 8-10 m. Thus, the 'Goldilock' depth (5-7 m) for CTW to live is characterised by moderate wave action, lower water temperature compared to the shallow depth and less abrasive sediment presence with The outcome is slight contradict from a study done by Rowley (2008) in Indonesian reefs at Wakatobi Marine National Park, Indonesia. However, all sampling sites in the Indonesian study are located at the exposed fringing reefs subjected to high sedimentation, moderate-high wave action and strong current. ...
Polychaetes from genus Spirobranchus is one of the distinctive organisms in the coral reef ecosystem due to a unique, colourful ‘Christmas tree’ shape of radiolar crown. The presence of Christmas Tree Worm (CTW) on hard coral species and its colour variations can be potentially used to determine the coral health status and tourism attractions. Nevertheless, information on CTW in Malaysia is lacking; thus, the specific habitat and colour variety for CTW, particularly at the east coast of Peninsular Malaysia are not well understood. Hence, the objectives of this study are to investigate the coral preferences and colour variety of Pacific CTW, Spirobranchus corniculatus at Pantai Pasir Cina, Bidong Island, South China Sea. Underwater surveys were done using a belt transect technique by SCUBA divers in three depth ranges, i.e. 2–4 m, 5–7 m, and 8–10 m during high tide. Numbers of S. corniculatus per coral colony and coral species were recorded. Everted CTWs were digitally photographed and colour corrected to reveal the true colour. A total of 274 S. corniculatus were found along the belt transects on the coral reef at Pantai Pasir Cina. The major percentage (60.2%) of S. corniculatus was found in depth between 5 and 7 m and live on hermatypic coral from genus Porites. However, only a small number of CTW were recorded living on other coral genera including Astreopora spp., Montastrea spp. and Montipora sp., and no CTW was recorded live as a symbiont with Acropora species. The CTW at Pantai Pasir Cina has five plain and four patterns of colours dominated by blue, followed by yellow, orange, green, white, striped blue, striped purple, striped white and striped brown. This study revealed the importance of massive coral in particular Porites species as CTW host at Pantai Pasir Cina, Bidong Island. The information could be beneficial for determining the coral reef status using CTW as indicator species and for proper underwater tourism management.KeywordsChristmas tree worm
Spirobranchus corniculatus
Coral reefBidong IslandSouth China Sea
... At the moment, genus Spirobranchus consists of 37 species and can be found in all coral reef regions in the world (Polychaeta 2021). Spirobranchus is considered a host generalist; the worms can live in almost all stony corals, including Scleractinia (anthozoan) and Hydrozoa (Millepora) (Rowley 2008;Hoeksema et al. 2020). Nevertheless, recent studies also reported that CTW could also live in various secondary hosts including mushroom coral, zoantharian, ascidian, octocorallia (soft coral), sponges, and live bivalve shells ten Hove 2014, 2017;van der Schoot et al. 2016;García-Hernández and Hoeksema 2017;Hoeksema et al. 2020). ...
... In this study, no CTW was found as a symbiont with staghorn coral Acropora sp. and other secondary hosts such as zoanthids, ascidians and soft corals. The absence of CTW on Acropora sp. is expected as other recent studies also exempting Acropora species among the list of CTW host (Song 2006;Rowley 2008;Perry et al. 2018) or recorded a very low number of individuals (Dai and Yang 1995). Interestingly, a high number of S. corniculatus larvae was recorded on live Acropora prolifera compared to other substrates (Marsden 1987). ...
... Also, the current around Bidong Island moves from north to south with the maximum speed of 0.22 m/s (Daud and Akhir 2015), which may reduce the opportunity for trochophore larvae of S. corniculatus to settle on a potential host at 8-10 m. Thus, the 'Goldilock' depth (5-7 m) for CTW to live is characterised by moderate wave action, lower water temperature compared to the shallow depth and less abrasive sediment presence with The outcome is slight contradict from a study done by Rowley (2008) in Indonesian reefs at Wakatobi Marine National Park, Indonesia. However, all sampling sites in the Indonesian study are located at the exposed fringing reefs subjected to high sedimentation, moderate-high wave action and strong current. ...
Geological characteristic provides an understanding of the geological evolution of island's landscapes. The geology of Bidong Island is defined based on the tectonic framework, rock formation and geomorphology. The tectonic setting of Bidong Island is related to the subduction of Paleo-Tethys beneath East Malaysia and Indochina which form the mountains and hills in Peninsular Malaysia. The rock formation of Bidong Island is a granitic rock as part of the Eastern Granite Province of the Southeast Asian Tin Belt. It is characterized by non-porphyritic to porphyritic granodiorite thus illustrate significant plutonic events in the region. The geomorphology features observed are rocky shore, headland, and sandy beach. Overall, this study suggested that Bidong Island presents a signature tectonic evolution that involved geological processes such as plutonism and volcanism, uplift and sea-level phenomenon. The geological value of Bidong Island provides scientific value for economic potential as an aspiring geopark for sustainable management of marine resources.KeywordsPlutonic-granitic rockEastern Granite ProvinceHolocene sea-level changes
... At the moment, genus Spirobranchus consists of 37 species and can be found in all coral reef regions in the world (Polychaeta 2021). Spirobranchus is considered a host generalist; the worms can live in almost all stony corals, including Scleractinia (anthozoan) and Hydrozoa (Millepora) (Rowley 2008;Hoeksema et al. 2020). Nevertheless, recent studies also reported that CTW could also live in various secondary hosts including mushroom coral, zoantharian, ascidian, octocorallia (soft coral), sponges, and live bivalve shells ten Hove 2014, 2017;van der Schoot et al. 2016;García-Hernández and Hoeksema 2017;Hoeksema et al. 2020). ...
... In this study, no CTW was found as a symbiont with staghorn coral Acropora sp. and other secondary hosts such as zoanthids, ascidians and soft corals. The absence of CTW on Acropora sp. is expected as other recent studies also exempting Acropora species among the list of CTW host (Song 2006;Rowley 2008;Perry et al. 2018) or recorded a very low number of individuals (Dai and Yang 1995). Interestingly, a high number of S. corniculatus larvae was recorded on live Acropora prolifera compared to other substrates (Marsden 1987). ...
... Also, the current around Bidong Island moves from north to south with the maximum speed of 0.22 m/s (Daud and Akhir 2015), which may reduce the opportunity for trochophore larvae of S. corniculatus to settle on a potential host at 8-10 m. Thus, the 'Goldilock' depth (5-7 m) for CTW to live is characterised by moderate wave action, lower water temperature compared to the shallow depth and less abrasive sediment presence with The outcome is slight contradict from a study done by Rowley (2008) in Indonesian reefs at Wakatobi Marine National Park, Indonesia. However, all sampling sites in the Indonesian study are located at the exposed fringing reefs subjected to high sedimentation, moderate-high wave action and strong current. ...
Crown-of-Thorns starfish (COTs), Acanthaster cf solaris is known as one of the most significance threats in coral reef ecosystem. During the COTs outbreak it caused extensive coral mortality and consequently lead to loss of habitat in other reef-associated organisms. It is important to investigate the environmental tipping point on COTs early life history stages to understand the limits for normal development of this starfish. In this study, the effects of projected ocean acidification conditions (pH: 7.4 and 7.8) were tested on fertilization success and larvae development rate of the COTs. The larvae development rate was investigated by measured the length and width of the larvae on 4th and 14th day of the experiment. The results showed that lowered seawater pH has no significance impact on the fertilization success rate. However, larvae size in the lowered pH treatments were significantly smaller than the control treatment (pH: 8.1). Length and width of COTs in lowered pH treatments were 40–46% and 28–47% smaller than the samples in control treatment, respectively. These findings indicated that COTs’ larvae may survived ocean acidification conditions. But larvae growth rate may delayed and their size reduced in the lowered pH seawater conditions.KeywordsBidong IslandOcean acidificationCoral reefsCrown-of-thorns starfishSeawater pHSouth China Sea
... At the moment, genus Spirobranchus consists of 37 species and can be found in all coral reef regions in the world (Polychaeta 2021). Spirobranchus is considered a host generalist; the worms can live in almost all stony corals, including Scleractinia (anthozoan) and Hydrozoa (Millepora) (Rowley 2008;Hoeksema et al. 2020). Nevertheless, recent studies also reported that CTW could also live in various secondary hosts including mushroom coral, zoantharian, ascidian, octocorallia (soft coral), sponges, and live bivalve shells ten Hove 2014, 2017;van der Schoot et al. 2016;García-Hernández and Hoeksema 2017;Hoeksema et al. 2020). ...
... In this study, no CTW was found as a symbiont with staghorn coral Acropora sp. and other secondary hosts such as zoanthids, ascidians and soft corals. The absence of CTW on Acropora sp. is expected as other recent studies also exempting Acropora species among the list of CTW host (Song 2006;Rowley 2008;Perry et al. 2018) or recorded a very low number of individuals (Dai and Yang 1995). Interestingly, a high number of S. corniculatus larvae was recorded on live Acropora prolifera compared to other substrates (Marsden 1987). ...
... Also, the current around Bidong Island moves from north to south with the maximum speed of 0.22 m/s (Daud and Akhir 2015), which may reduce the opportunity for trochophore larvae of S. corniculatus to settle on a potential host at 8-10 m. Thus, the 'Goldilock' depth (5-7 m) for CTW to live is characterised by moderate wave action, lower water temperature compared to the shallow depth and less abrasive sediment presence with The outcome is slight contradict from a study done by Rowley (2008) in Indonesian reefs at Wakatobi Marine National Park, Indonesia. However, all sampling sites in the Indonesian study are located at the exposed fringing reefs subjected to high sedimentation, moderate-high wave action and strong current. ...
An assessment of modern benthic foraminiferal species occurrences was carried out in the coral reefs environment of Bidong Island, Terengganu. Foraminiferal samples were collected by SCUBA divers at 12 transects around the island. Rose Bengal dye was mixed into formalin (10%) during the preservation process. It was used to distinguish living specimens from empty tests in the samples. There were 32 species of benthic foraminifera found in the study area. These species belong to two orders (Rotaliida and Miliolida), ten families and 15 genera. Amphistegina was the most dominant genus that occurred in all sampling stations. This study is the first record of benthic foraminiferal occurrence in Bidong Island, Terengganu. Fossil benthic foraminifera are used as proxies in interpreting past environments especially in the fields of paleobathymetry, paleoenvironment and paleoclimate. Modern benthic foraminiferal assemblages are useful in aiding the interpretations of past environments using these proxies. Modern benthic foraminifera can also be applied as bioindicators in environmental monitoring studies.KeywordsBidong IslandCoral reefsDistributionMalay basinModern benthic foraminifera
... At the moment, genus Spirobranchus consists of 37 species and can be found in all coral reef regions in the world (Polychaeta 2021). Spirobranchus is considered a host generalist; the worms can live in almost all stony corals, including Scleractinia (anthozoan) and Hydrozoa (Millepora) (Rowley 2008;Hoeksema et al. 2020). Nevertheless, recent studies also reported that CTW could also live in various secondary hosts including mushroom coral, zoantharian, ascidian, octocorallia (soft coral), sponges, and live bivalve shells ten Hove 2014, 2017;van der Schoot et al. 2016;García-Hernández and Hoeksema 2017;Hoeksema et al. 2020). ...
... In this study, no CTW was found as a symbiont with staghorn coral Acropora sp. and other secondary hosts such as zoanthids, ascidians and soft corals. The absence of CTW on Acropora sp. is expected as other recent studies also exempting Acropora species among the list of CTW host (Song 2006;Rowley 2008;Perry et al. 2018) or recorded a very low number of individuals (Dai and Yang 1995). Interestingly, a high number of S. corniculatus larvae was recorded on live Acropora prolifera compared to other substrates (Marsden 1987). ...
... Also, the current around Bidong Island moves from north to south with the maximum speed of 0.22 m/s (Daud and Akhir 2015), which may reduce the opportunity for trochophore larvae of S. corniculatus to settle on a potential host at 8-10 m. Thus, the 'Goldilock' depth (5-7 m) for CTW to live is characterised by moderate wave action, lower water temperature compared to the shallow depth and less abrasive sediment presence with The outcome is slight contradict from a study done by Rowley (2008) in Indonesian reefs at Wakatobi Marine National Park, Indonesia. However, all sampling sites in the Indonesian study are located at the exposed fringing reefs subjected to high sedimentation, moderate-high wave action and strong current. ...
Forests not only function as habitat but also provides food sources to various terrestrial communities so that this ecosystem can sustain its function. With trees, forest ecosystems can support various flora, microbes, insects, birds, reptiles and mammals. Unfortunately, since in 1975, the trees of forested islands are suffering from land-clearing due to human inhabitation and this similar incidence is witnessed at Bidong Island. To update a checklist of plants on this island, a series of field surveys which includes new and former locations were held in 2009, 2015 and 2019. Bidong Island harbours a total of 201 plant species, representing 66 family and 142 genera. It includes shrub, medicinal plants, timber and plants that are heritage to Malaysia as food. To secure ecological functions of Bidong Island, particularly in forest conservation management, it is recommended that monitoring and legal protection of the remaining forested areas are needed.KeywordsBiodiversityBiogeographyDipterocarpEcosystem serviceSouth China SeaTropical island
The primary objective of this study was to investigate the densities and age structure of Christmas tree worms Spirobranchus sp. (Serpulidae, Polychaeta), on colonies of massive stony corals of the genus Porites, which have not been reported before in the region. Pulau Sempu, East Java, Indonesia. Pulau Sempu is a small island and also the sole remaining nature reserve within the region of. This small island is encompassed by shallow and narrow fringing reefs, characterized by a composition of algae and an occurrence of hard corals, specifically from genera Porites, Pocillopora, and Coelastrea (formerly known as Goniastrea). The majority of Porites specimens creating a narrow reef encompassing the island is colonized by boring polychaets known as the Christmas tree worms, Spirobranchus sp., which inhabit the interior of coral skeletons. Studies were carried out in two specific locations within the nature reserve Pulau Sempu, i.e., Watu Mejo and Waru-Waru. Two species: Spirobranchus corniculatus and Spirobranchus cruciger, have been identified dwelling on corals. Our findings indicated that the density of the worms residing in large Porites was 8.62 individuals/ m2 in Watu Mejo and 9.02 individuals/m2 in Waru-Waru. The age of the worms found on Pulau Sempu, as determined by operculum size, ranged between 14 and 22 years. Worm age differ among study sites with older individuals observed at Waru-Waru.
