FACTORS AFFECTING FEEDING CHARACTERISTICS ORANGE MUD CRAB, Scylla olivacea IN PATTANI BAY, THAILAND

 Sofiyudin Maae¹, Sukree Hajisamae², Pornpimon Chuaduangpui¹, Husneya Rensep², Saweit Chaimongkol²

¹Aquatic Science and Innovative Management Division, Faculty of Natural Resources, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand

²Department of Agricultural and Fishery Science, Faculty of Science and Technology, Prince of Songkla University, Pattani 94000, Thailand

*Corresponding author: fee0883@gmail.com

The purpose of this study is to investigate the impacts sex, size and habitat on feeding characteristics of orange mud crab, Scylla olivacea. Samples were collected from four study sites along Pattani bay, Thailand during March 2022 to July 2022 using crab traps. The crab samples were soaked immediately in cold water and immediately frozen. They were later identified, weighted and measured. The stomachs were dissected, preserved in 70% alcohol. Stomach contents were identified and measured. It was found that fish was the major food component in the stomachs (55.30%) followed by bivalve (12.49%), crab (9.09%), gastropod (4.98%) and shrimp (3.03%). The fullness indices varied significantly between size class and study site (P<0.05). The average number of food items were not affected by sex, size class and habitats (P>0. 05). Result from this study indicates that small size crab fed more intensively, followed by medium and large sizes. Habitats is another factor controlling feeding intensity of this crab species in Pattani bay. This study contributes to the knowledge on feeding characteristics of this crab in this area and can be applied for the management of this species.

Keyword: Feeding, Habitats, Orange mud crab, Pattani bay, Scylla olivacea

ABUNDANCE AND DISTRIBUTION OF FOUR-FINGERED THREADFIN FISH, ELEUTHERONEMA TETRADACTYLUM AND ITS RELATIONSHIP WITH OTHER FISH SPECIES IN PATTANI BAY, THAILAND

 Teuku Haris Iqbal^1*, Sukree Hajisamae¹, Apiradee Lim¹, Sitisak Jantarat¹, Wen-Xiong Wang², Karl W. K. Tsim^,3

 ¹Faculty of Science and Technology, Prince of Songkla University, Pattani, 9400 Thailand

²School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, 999077 China

³Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077 China

^*Corresponding author: teukuharisiqbal@gmail.com

Pattani Bay is located in the lower part of Gulf of Thailand and known as an important fishing ground for many fish species, including the four-fingered threadfin fish, Eleutheronema tetradactylum. The study was conducted to determine distribution of four-fingered threadfin fish, and its relationship with other fish community residing in Pattani Bay, Thailand. Fishes were collected from three different habitats; outer, middle, and inner of the bay’s mouth, from January 2021 to January 2022 by a traditional threadfin fish’s gill net. A total of 194 individuals of E. tetradactylum and 1,034 of the other 42 species were caught. It was found that Hilsa kelee was the most dominant fish caught together with threadfin fish (42.33%), followed by E. tetradactylum (14.88%) and Otolithes ruber (11.20%). Spatially, E. tetradactylum was found abundantly in the outer part of the bay together with O. ruber, H. kelee was found mainly in the inner bay. Seasonally, E. tetradactylum was found abundant in dry season together with H. kelee and, while O. ruber was in moderate season. However, Analysis of Variance (ANOVA) indicated that there was no significant difference between number and biomass of all fish collected based on neither season nor study site (P>0.05). The diversity index (H’) varied between habitat, where highest in the middle part (2.29) and lowest in the inner part (1.75). Seasonally, the highest H’ was in moderate rainy season (2.22) and lowest in the rainy season (2.00). Additionally, size of E. tetradactylum and other 10 dominant fish species varied among habitat and season (p<0.01). This data can be served as basic information for further management of fish community caught by a threadfin fish net.

Keywords: Pattani Bay, fish composition, fish diversity, fish community, water parameter

SPECIES DIVERSITY OF ECHINODERM IN PATTANI BAY, THAILAND

 Jitima Suwanmala*, Supat Khongpuang, Amarin Thongwaan, Sofiyudin Maae

Department of Agricultural and Fishery Science, Faculty of Science and Technology, Prince of Songkla University, Pattani, Thailand

*Corresponding author: jitima.s@psu.ac.th

Species diversity of Echinoderm in Pattani Bay, Thailand. Samples were collected from 8 sampling stations with 3 replications during September 2018 to February 2020. Geological position of all stations was recorded by a handheld GPS. Additional samplings were also collected from local fishing gears. The study results founded 9 families of echinoderm, composed of 11 genus and 12 species, which were Phyllophorus sp. (sea cucumber), Thyone okeni (sea cucumber), Molpadia roretzi (sea cucumber), Acaudina leucoprocta (sea cucumber) Temnopleurus toreumaticus (sea urchin), Amphiura sp. (brittle star), Ophiactis sp. (brittle star), Ophiocnemis marmorata (brittle star), Macrophiothrix sp. (brittle star) Astropecten indicus (sea star), Anthenea regalis (sea star) and Anthenea pentagonula (sea star). Some water parameters including water temperature, salinity, depth, dissolve oxygen and pH were analyzed. Those parameters values varied from 27.30-33.37 ^oC, 4-33 ppt, 30-260 cm, 4.13-11.07 mg/l and 7.41-9.07, respectively. Two-way ANOVA showed no interaction effects (p>0.05) of month and station (Month*Station) on the number of species, but significant different (p<0.05) among stations. Abundance of echinoderm (individual/1000m²) in each month and station was highly significant statistical difference (p<0.001). The abundance of T. toreumaticus, the dominant species, was highly significance among (p<0.01) different months. The abundant of sea cucumber (Phyllophorus sp.), the second dominant species, was found highly significant statistical difference (p<0.001) among months. Therefore, echinoderms surveys are useful in utilization management planning. These is an important database in further research in echinoderm leading to aquaculture development, conservation and distributing knowledge to the fishermen considering on the importance of echinoderms to the Pattani Bay.

Keywords: Species diversity, abundance, Echinoderm, Pattani Bay

SPECIES COMPOSITION, ABUNDANCE, DISTRIBUTION, AND DIVERSITY OF SEAWEEDS IN BANATE, ILOILO

 Allen Patrick Araneta¹, Jonalyn P. Mateo^1,2*, Anicia Q. Hurtado², Maria Rovilla J. Luhan²

 ¹Institute of Marine Fisheries and Oceanology, University of the Philippines Visayas Miagao, Philippines 5023

²Institute of Aquaculture, University of the Philippines Visayas Miagao, Philippines 5023

*Corresponding author: jpmateo@up.edu.ph

The municipality of Banate is strategically located in Banate Bay, one of the significant bodies of water in Iloilo, which is known to be rich in marine resources. Marine macrophyte composition in the area is poorly documented which contributes to the inadequacy of knowledge of the identities and varieties of relevant seaweed species. This study was conducted to determine the species composition, abundance, distribution, and diversity of seaweeds in Banate, Iloilo. The line transect-quadrat method was used to identify and quantify the seaweeds abounding the 8-kilometer coast of the municipality. Representative voucher specimens were also taken, whether within or outside the transect line, for herbarium documentation and archiving. A total of 9 different species of seaweeds were identified in the study area belonging to Chlorophyceae (Ulva clathrata and Codium arabicum), Rhodophyceae (Gracilaria salicornia, Acanthophora specifera, Acanthophora sp., Amphiroa fragilisima, and Hypnea sp.), and Phaeophyceae (Padina minor and Sargassum sp.). Percentage cover (C), percentage contribution, Shannon’s Diversity Index (H), and Pielou’s Measure of Species Evenness (J) were calculated to determine species composition, abundance, and diversity in the area. Of the 17 study stations, only eight showed seaweed cover with station 1 obtaining the highest cover. The dominant species is Gracilaria salicornia occupying 87.15% of the total cover in the area. Banate has extremely low marine seaweed diversity (H = 0.05). Of all the stations, only two showed diversity indices, both of which are located in San Salvador. However, diversity values for Stations 15 and 16 are considered extremely low at H = 0.21 and H = 23, respectively. The presence of possible bioindicator species at several of the sites may potentially be utilized as possible indicators of eutrophication and coastal pollution since the specimens were collected during summer.

Keywords: Seaweed diversity, Banate, Assessment

CARBON SEQUESTRATION IN SEAGRASS BED: A CASE STUDY IN TANGKHEM BAY, PHUKET, THAILAND

 Fadeelah Saewaeng¹, Suphasit Bunphienphon², Peeradon Kirdpol², Supat Khongpuang¹*

¹Department of Agricultural and Fishery Science, Faculty of Science and Technology, Prince of Songkla University, Pattani, Thailand

²Phuket Marine Biological Center (PMBC), Department of Marine and Coastal Resources, Phuket, Thailand

*Corresponding author: supat.k@psu.ac.th

Study on carbon sequestration of a 16-hectare seagrass bed in Tangkhem Bay, Phuket, Thailand, was conducted during November 2021-March 2022. Thirteen sampling stations were adopted. Nine stations were on 3 line transects in seagrass cover area while the rests were randomly selected in non-seagrass cover site. Seagrass samples were collected using a 25*25 cm² quadrat. Sediment samples were collected by coring. Organic carbon (OC) in seagrass and sediment were investigated using lost on ignition (LOI) approach. The results found that the average biomass of seagrass was 2.29±0.10 Mg.ha^-1. Average OC in seagrass was 0.73±0.08 MgC.ha^-1, dividing into aboveground OC of 0.33±0.03 MgC.ha^-1 and belowground OC of 0.40±0.05 MgC.ha^-1. Total OC absorbed by seagrass in the bay was 11.68 MgC. Average OC in sediment was 26.91±8.72 MgC.ha^-1; calculated from 27.90±9.86 MgC.ha^-1 in the seagrass cover area and 24.68±5.94 MgC. ha^-1 in the non-seagrass cover site. The mean OC values of the aforementioned areas were not significant difference (p<0.05). Total OC absorbed by sediment was 446.40 MgC. The sediment within a 60-cm depth was divided into 12 identical layers to investigate OC along the depth profile. Average OC values of each layer varied from 1.33±0.63 to 4.60±3.45 MgC.ha^-1 with significant difference (p<0.05). The average OC in sediment increased from the sediment surface, reached the maximum value at the sediment depth of 35 cm and then gradually decreased. Polynomial function of Y (average OC in sediment; MgC ha^-1) and X (sediment depth; cm) can be illustrated as Y = -0.0011X² + 0.1359X + 3.1091; R² = 56.41%. In summary, the total OC sequestration by seagrass bed in the study area was 458.08 MgC., shared mainly by the OC in sediment. Moreover, the OC accumulation in sediment can be moderately predicted by using sediment depth as a predictor.

Keywords: Carbon sequestration, Seagrass, Seagrass bed, Tangkhem Bay, Phuket

CARRAGEENAN QUALITIES OF DIFFERENT FARMED KAPAPPHYCUS VARIANTS IN SAN DIONISIO, ILOILO

 Yessamin T. Lebaquin¹, Jonalyn P. Mateo^1,2*, Anicia Q. Hurtado²

¹Institute of Marine Fisheries and Oceanology, University of the Philippines Visayas Miagao, Philippines 5023

²Institute of Aquaculture, University of the Philippines Visayas Miagao, Philippines 5023

*Corresponding author: jpmateo@up.edu.ph

Philippines is one of the major producers of the red seaweed Kappaphycus, which is a source of carrageenan used mainly as food ingredient in beverages, dairies, pastries. Although there are different species and color morphotypes of Kappaphycus, most studies have focused on two species without comparing the carrageenan qualities of the different varieties. Basic knowledge on the identification of the variants and correlating it to its morphological characteristics and carrageenan quality can help the seaweed industry focus on varieties with good qualities. This study evaluated the morphological differences and carrageenan quality of four cultivars of Kappaphycus (K. alvarezii var. Rafael and Tambalang, and K. striatus var. Barako and Rafael) from San Dionisio, Iloilo. Seaweed samples were collected from Brgy. Tiabas, San Dionisio, Iloilo during wet season. Morphological features were noted, and the key distinctions were all observed. For the carrageenan quality, semi-refined extraction method was used. Moisture content (%), carrageenan yield (%), viscosity (cPs), and gel strength (g cm^-2) were measured and obtained using Brookefield Synchro-lectic viscometer and El Shimadzu gel tester. Results showed that moisture content ranged from 8.48-21.03% which has passed the PNS 85:2021 and are classified to be class A in terms of moisture with the highest value obtained by K. alvarezii var. Tambalang. Carrageenan yield ranges from 38.57-47.89%, although, the yield could still increase if the seaweeds were cultivated even further based on optimum cultivation duration. For the viscosity, the value ranges from 17.33 to 58.39 cP which are within the FAO’s standard and PNS 601:2008. Meanwhile, the gel strength ranges from 330.42-587.19 g cm⁻², and highest gel strength values were exhibited by K. alvarezii var. Rafael. To summarize, K. alvarezii var. Rafael has better carrageenan quality during wet season in Brgy. Tiabas, San Dionisio than the var. Tambalang and K. striatus var. Barako and Rafael. Thus, recommending its cultivation to help seaweed farmers gain profit.

Keywords: Kappaphycus sp., wet season, carrageenan quality, sustainability