UMTAS 2013 Advancements in Marine and Freshwater Sciences 426 An Assessment of Coastal Fish Community Adjacent to Prawn Farms at Kuala Selangor, Selangor Harinder Rai Singh 1,2,* , Mohd Azham Yahya 1 and Mohd Farid Ismail 1 1 Faculty of Applied Sciences, 2 Centre for Biodiversity and Sustainable Development, Universiti Teknologi MARA 40450 Shah Alam, Malaysia *Email: harinderrai.singh@gmail.com Abstract Mangrove forests are among the world’s most productive ecosystems. They enrich coastal waters, yield commercial forest products, protect coastlines, and support coastal fisheries. Anthropogenic activities such as illegal logging, prawn aquaculture, land reclamation industrial and domestic use and pollutant runoff are threats to mangroves. This paper reports on the coastal fish community sampled adjacent to land based (previously mangroves) prawn pond farms stretching some 10 kilometers along the Kuala Selangor coast. The objectives of the study were to determine the species richness, diversity and community indices of the sampled fish community. A total of 22 families comprising 42 fish species were sampled from the study area by utilising gill nets and barrier nets. The Engraulidae were the most represented and made up 46% of the total catch, followed by the Mugilidae (13%), Clupeidae (12%), Leiognathidae (10%), Ariidae (9%) and the remaining 17 families made up 10% of total population. Thryssa kammalensis (n=839), was the most abundant fish species sampled. The species richness (Margalef’s D) was 5.17, Shannon Weiner Diversity (H’) was 2.34, while species evennes (J) was 0.62. Size distribution of the ten most dominant fishes showed that five fish species can be considered as juveniles (Arius maculatus, Liza vaigiensis, Liza subviridis, Arius sp. and Johnius carutta) while the rest were either sub adults or adults. The loss of mangroves through human enroachment especially prawn aquaculture if not checked can lead to lowering of fish stocks in coastal waters. Introduction Mangroves are example of natural resources that promote coastal habitat complexity, enrich coastal waters, yield commercial forest products, protect coastline and supports coastal fisheries (Kathiresan & Bingham, 2001). Notwithstanding their importance, global mangrove area declined from 18.8 million hectares (ha) in 1980 to 15.6 million ha in 2005 but there has been a slowdown in the rate of mangrove loss from the same period (FAO, 2007). Asia suffered the largest net loss due to change in land use since 1980’s with more than 1.9 million ha destroyed while in in Malaysia, losses have been estimated at 128,000 hectares from 1975 (700,000 ha) to 2000 (572,000 ha) (Aizpuru e al., 2000). Part of the mangrove loss has been due to mangrove conversion to prawn aquaculture. The conversion of mangroves to prawn aquaculture has been increasing due to high intensity aquaculture techniques with global farmed shrimp production estimated at $7 billion USD in 2000 (FAO, 2002). In Thailand, prawn farming was put into practice since the early 70’s while in Bangladesh the industry took off during the early 1980’s and has been growing ever since (Akhter, 2010). It is estimated that 200,000 ha of mangroves were deforested, with a third of the area transformed for shrimp farming in Thailand (Aksornkoae et al., 2004) and similar patterns were also observed in India (Hein, 2000). In Malaysia the industry is not as big as in Thailand but has shown increase in recent years.