Species composition and toxicity of by-catch crabs in the EEZ Sarawak

• Main Author: Siti Nur Ashieqa, binti Hasli
• Format: Final Year Project Report
• Language: English
• Published: Universiti Malaysia Sarawak, (UNIMAS) 2016
• Subjects: SH Aquaculture. Fisheries. Angling
• Online Access: http://ir.unimas.my/id/eprint/15481/4/Siti%20Nur%20Ashieqa%28fulltext%29.pdf; http://ir.unimas.my/id/eprint/15481/

One hundred and sixty four samples ofcrabs were collected by-catch from 35 stations in EEZ Sarawak., during cruises ofM. V. SEAFDEC 2, 18 August -17 September 2015. The crab samples were collected using otter trawl net with the depth ofcapture range from 22 m to 140 m depth. Seven different Families, composed of23 different species were identified based on morphology characteristics. The composition ofcrabs at each station were recorded. The species frequently found predominant in each Leg were Charybdis miles, Charybdis acutidens and Calappa spp. While for toxicity studies, 10 species were extracted and analyse to assess their toxin propertise. Among the ten species analysed for Saxitoxin (STX) using Thin Layer Chromatography (TLC) and High Performance Liquid Chromatography (HPLC) none of the samples showed positive results indicating these species does not contained STX as the major toxins. However, for tetrodotoxin (ITX) analysis using LC-MS/MS analysis, two of the species are classified as weakly toxic and one of the species being classified as moderately toxic. The data collected in this study will be the basis ofcrab composition that using trawl and provide useful toxicity data ofcrabs in Sarawak waters.