WATER QUALITY AND FISH FAUNA IN LAKEWOOD LAKE ZAMBOANGA DEL SUR, PHILIPPINES

A pioneering study was done on Lake Lakewood, a freshwater lake located in western Mindanao, Philippines to lay down an environmental baseline for the lake ecosystem focusing on limnology and aquatic faunal biodiversity. In situ determinations were done on depth-integrated grab samples using portable probe/digital instruments concerning the following water quality parameters: water temperature, TDS, pH, electrical conductivity, chl a, and a, depth profile of DO. Actual fishing and identification of the fish species caught was done to address aquatic faunal biodiversity. Depth profiles of WT and DO within a 10-m deep water column gave ranges of 26.6 (10-m) - 28.8 0C (surface); and 5.96 mg.L-1- 7.8 mg.L-1, respectively. The results gave no significant spatial variation. Surface determinations of TDS was 57.44 ? 65.11mg.L-1, pH, 7.9-8.8; and EC, 0.07 - 0.09 μS/cm. Chl a that ranged from 0.6 to2.3 mg.L-1; and the BOD, 0.37 ? 4.30 ml.L-1 both yielded significant spatial differences. Chl a significantly differentiated among stations. Eleven freshwater fish taxa were identified. Three species belonged to Cyprinidae family, and eight species were of the Clariidae, Osphronemidae, Channidae, Anguillidae, Cichlidae, Hemiramphidae, Anabantidaeand Gobiidae. One commercialized cyprinid, locally known as Porang is endemic to the lake. Four shellfishes taxa belonged to the families of Pomacea, Lymnaeidae and Corbiculidae and Viviparidae. Recommendations concerning resource conservation and improved management strategies are discussed.