Sea urchins are marine benthos that live in different habitats available at shallow and deep waters. In Malaysia, Sabah is the only state that exploits sea urchins without knowing the status of natural stocks. This study identified the sea urchin species diversity at shallow subtidal zones in east coast of Borneo which is part of the Coral Triangle. Belt transects were deployed to quantify the species composition and qualitative observations on the habitat types were also noted. Simultaneously, documentation of species available in several wet markets was gathered through impromptu conversation with the sellers. In this study, a total of 10 species of sea urchin were recorded from 18 sampling sites, namely,
Sea urchins (local name: Landak Laut, Tayum, Tehe-tehe) are one type of benthos (phylum Echinodermata, class Echinoidea) which has spherical shape and is covered with long movable spines that live in different marine habitats, from intertidal [
About 1,000 species of sea urchins have been reported world wide [
In some Asian and Mediterranean countries, sea urchins are important marine resource due to the highly prized roe [
Thus, it is timely to make proper documentation about sea urchins’ resources for future research needs because collection of sea urchins in such a large amount could also pose a threat to the natural stocks. Therefore, this research was designed to identify species of sea urchins in shallow waters of Sabah. Data gathered will be useful in providing information on the natural populations of fisheries important species of sea urchins in Sabah, which can be used for conservation and sustainable resource management.
This research was conducted in Sabah shallow waters which involved 29 study sites in six districts (Figure
Sampling period according to district.
Sampling period | District (station number) |
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4 Dec. 2010 | Tawau (9–14) |
6-7 Dec. 2010 | Semporna (15–18) |
2 Feb. 2011 | Semporna (19) |
9 Dec. 2010 | Lahad Datu (20–25) |
11 Dec. 2010 | Sandakan (26–29) |
12-13 Dec. 2010 | Kudat (2 and 6) |
20 & 25 Nov. 2011 | Kudat (1) & Kudat (3, 4, and 5) |
3-4 Dec. 2011 | Kota Belud (7 and 8) |
(a) East coast of Borneo Island. (b) The study sites within six districts in Sabah, Malaysia, as follows: 1-Limau-Limauan Beach, 2-Bak-Bak Beach, 3-Suangpai Village Beach, 4-West Simpang Mengayau, 5-East Simpang Mengayau, 6-Kelambu Beach, 7-West Mantanani Island, 8-East Mantanani Island, 9-Udin River, 10-Bingkulan River, 11-Tiram River, 12-Pasir Puteh, 13-Batu Payong, 14-Indrasabah Village, 15-West Manampilik Island, 16-East Manampilik Island, 17-Omadal Island, 18-Bum-Bum Island, 19-Larapan Island, 20-Burung Island, 21-Babi Island, 22-Tiga Island, 23-Tengah Island, 24-West Sakar Island, 25-East Sakar Island, 26-Papan Jambatan, 27-Tikus Island Reef, 28-Tikus Island, and 29-Menangin Island.
Determination of sea urchin species composition (%) was carried out at selected study sites by snorkelers. Three to five belt transects (5 m × 25 m) were laid perpendicular to the coastline at 11 sampling sites (Stations 1, 3, 4, 5, and 6 in Kudat district; Stations 15, 16, and 18 in Semporna district; Stations 20, 22, and 25 in Lahad Datu district) and all sea urchins found within the transect area were counted. However, for study sites that experienced bad sea condition or exhibited patchiness in sea urchin population, the number of sea urchins encountered was counted randomly and included in reporting the species occurrence. Several specimens were collected for further species identification work in the laboratory using identification keys. The presence and absence of sea urchin for each district and sampling site were presented in table form. The total number of individuals for each sea urchin species was converted into percentage to show the species composition and presented in pie chart and table. Simultaneously, habitat description and seaweed existing at each site were also recorded. Through visits to several wet markets in each district, documentation of edible species was gathered through impromptu conversation with the sellers and local people.
Physicochemical parameters, namely, pH, dissolved oxygen, temperature, turbidity, and salinity, were recorded
Throughout this study, a total of 10 sea urchin species from four orders, five families, and nine genera had been identified (Table
The classification of sea urchin collected in Sabah.
Order | Family | Genera | Species |
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Cidaroida | Cidaridae |
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Diadematoida | Diadematidae |
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Temnopleuroida | Temnopleuridae |
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Echinoidea | Echinometridae |
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Toxopneustidae |
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In total, 13 sea urchins species were already identified in Malaysia (Table
Comparison of species lists between the present study and other records in Malaysia. (+): present and (−): absent.
Species | Present study | Other records in Malaysia [ |
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+ | − |
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+ | + |
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+ | + |
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+ | + |
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− | + |
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+ | − |
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+ | + |
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+ | + |
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+ | − |
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+ | + |
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+ | + |
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− | + |
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− | + |
The total number of sea urchins found in this study was 3,441 individuals. Based on the overall species composition (Figure
Species composition of sea urchins found in Sabah waters.
In terms of species occurrence based on 29 sampling sites, 18 sites recorded the presence of sea urchin which ranged from a minimum of one species to a maximum of seven species found (Table
The presence and absence of sea urchin species in each sampling site.
Species | District | ||||||||||||||||||||||||||||
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Kudat | Kota Belud | Tawau | Semporna | Lahad Datu | Sandakan | ||||||||||||||||||||||||
Site number | |||||||||||||||||||||||||||||
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | |
D. set |
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D. sav |
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P. imp |
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E. cal |
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M. glo |
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S. sph |
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E. mat |
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P. mac |
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T. pil |
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T. gra |
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Number of species | 1 | 1 | 3 | 2 | 3 | 4 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7 | 7 | 4 | 4 | 2 | 1 | 1 | 2 | 1 | 1 | 2 | 0 | 0 | 0 | 0 |
D. set:
The species abundance (%) of sea urchins according to districts showed that family Diadematidae which is composed of three species (
The species abundance (%) of sea urchins according to districts, (−): absent.
Species | Abundance (%) | ||
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Kudat | Lahad Datu | Semporna | |
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− | − | 0.74 |
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98.38 | 98.62 | 54.21 |
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− | 1.25 | 32.64 |
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0.94 | 0.13 | 6.65 |
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0.34 | − | 0.15 |
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− | − | 0.44 |
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− | − | 0.30 |
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− | − | 0.44 |
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− | − | 1.92 |
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0.34 | − | 2.51 |
The reasons for the difference of species composition, species abundance, and species occurrence at each study site could be related to the physicochemical parameters of water (Table
Range of mean values of
District | Range of mean value | ||||
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pH | Temperature |
Turbidity |
Salinity |
DO | |
Kudat | 7.34–8.18 | 31.00–33.00 | 0.79–2.37 | 30.00–31.00 | 9.75–12.81 |
Kota Belud | 7.18–7.31 | 30.10–30.60 | 4.59–8.72 | 31.00–34.00 | 7.04–7.47 |
Tawau | 6.10–7.89 | 29.50–31.00 | 4.40–53.50 | 30.00–33.00 | 4.95–7.97 |
Semporna | 7.96–8.19 | 27.50–29.60 | 0.34–1.06 | 33.00–35.00 | 7.02–7.73 |
Lahad Datu | 7.83–8.10 | 29.60–31.70 | 0.00–0.63 | 32.00–35.00 | 7.07–11.75 |
Sandakan | 7.60–7.82 | 28.90–29.40 | 3.85–17.34 | 34.00–35.00 | 6.23–6.89 |
Seagrass and seaweed are the main diet for most sea urchins such as
Results showed that the species occurrence of sea urchins seems to be influenced by availability of suitable habitats such as coral reef, sea grass, and seaweed at the four districts. General description of each sampling site involved was recorded in order to know the habitat of sea urchin (Tables
The description of habitat at each sampling site by districts.
District | Sampling site | Description |
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Kudat | Limau-Limauan Beach | Rocky areas, coral rubbles |
Bak-Bak Beach | Rocky areas, seagrass bed, seaweed | |
Suang Pai Beach | Coral reef, seaweed, seagrass | |
West Simpang Mengayau | Rocky areas (big rocks), seaweed, coral reef | |
East Simpang Mengayau | Seagrass, seaweed, coral reef, rocky areas (small rocks) | |
Kelambu Beach | Rocky areas, coral reef, coral rubbles, debris | |
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Kota Belud | North Mantanani | Reef ball, seagrass, seaweed, coral reef |
South Mantanani | Seagrass, seaweed, debris | |
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Tawau | Udin Estuary | Seaweed ( |
Bingkulan Estuary | — | |
Tiram Estuary | — | |
Pasir Puteh Estuary | Rocky areas | |
Batu Payong | Rocky areas | |
Inderasabah Village | Fishing village | |
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Semporna | West Manampilik Island | Coral reef, rocky areas, seagrass, less seaweed |
East Manampilik Island | Coral reef, rocky areas, seagrass, seaweed, coral rubble | |
Omadal Island | Coral reef, seaweed, rocky areas | |
Bum-Bum Island | Coral reef, seaweed, seagrass | |
Larapan Island | Coral reef, seaweed | |
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Lahad Datu | Burung Island | Less coral, rocky areas, sandy area, coral rubbles, seaweed |
Babi Island | Rocky areas, coral rubble | |
Tiga Island | Coral reef | |
Tengah Island | Coral reef | |
West Sakar Island | Coral reef, rocky areas, sandy area | |
East Sakar Island | Coral reef, rocky areas, sandy area | |
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Sandakan | Papan Jambatan | Rocky areas |
Menangin Island | Rocky areas, sandy area | |
Tikus Island Rocky Areas | Rocky areas | |
Tikus Island | Rocky areas, sandy area |
List of main seaweeds genera available at each district.
District | Seaweed genera |
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Kudat |
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Kota Belud | Not collected |
Tawau | Not collected |
Semporna |
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Lahad Datu |
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Sandakan |
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Pristine or less disturbed natural habitats offer ample food sources to sea urchins and also play important role in specific behaviour of sea urchins towards their survival [
Furthermore, habitat specific cues also play an important role in sea urchin larval settlement and population recruitment [
Sea urchin resources in Sabah are being exploited for local consumption without any regulation. Simple traditional method was used for sea urchin collection by Bajau Semporna and Ubian ethnics. Semporna has been identified as the main district in Sabah that harvests and markets sea urchin the most. A total of six species of edible sea urchin have been identified:
Overall, specific factors associated with sea urchin species diversity in the east coast of Borneo are not clear yet and may involve very complex abiotic-biotic interactions which need to be addressed in future. Nevertheless, findings of this study managed to give partial information on sea urchin resources of Sabah which is part of the Coral Triangle since the species checklist documented did not cover the deeper waters (>4 m) and the west coast of Sabah and thus may underestimate the real sea urchin diversity. However, these findings are useful in providing ecological information on the natural populations of fisheries important species of sea urchins in Sabah, which can be used for conservation and sustainable resource management.
A total of 10 species of sea urchin were recorded from 18 sampling sites, namely,
The authors declare that there is no conflict of interests regarding the publication of this article.
This project was supported by MOHE Fundamental Research Grant Scheme [07(02)/759/2010(45)]. Thanks are due to all support staffs and local people involved in this study for unlimited assistance during the field trips and data collection.