The Klong U-Tapao Basin in southern Thailand has many canals, with U-Tapao and Waad Canals being the two most important ones in Songkhl Province. Both of them collect natural and discharged water from rural areas and from Hat Yai City and drain into Songkhla Lake. U-Tapao Canal originates from the Sankarakiri Mountain Range and Ton Nga Chang Canal while Waad Canal starts in the Khao Ban Thad Mountain Range at Ton Nga Chang Wildlife Sanctuary. U-Tapao Canal is 90 km long, while Waad Canal is only 37 km in length (Royal Thai Survey Department 1997 a, b, c). The flora and fauna are very rich in the watershed area of Ton Nga Change Wildlife Sanctuary, but there are few reports on species diversity, aside from studies of ant diversity (Watanasit et al. 2000; Watanasit & Noon-anant 2005; Watanasit et al. 2005b).