Pond and wetland ecology in relation to mosquito larvae

Abstract

Ryakitanga ponds were sampled from May to November 2005. Three habitats comprising of one open water wetland and five fishponds were purposively selected basing on their biophysical characteristics. These habits were: Open water wetland (P.1), poorly maintained fishponds (FP.2, FP.5 and FP.6) and poorly maintained fishponds (FP.3 and FP.4). Factors that may influence mosquito development, including electrical conductivity, dissolved oxygen, pH, temperature, and turbidity, were measured in the three habitats bimonthly and percent vegetation cover was estimated. Mosquito larvae were collected using a 350ml white sampling dipper, identified and counted. Mean mosquito larvae abundance in ponds P.1, FP.2, FP.3, FP.4, FP.5 and FP.6 were: Zero, 0.63, 0.05, 0.01, 0.42 and 0.06 respectively and One-way ANOVA showed a significant pond-to-pond variation in mosquito larvae abundance (F=12.99, P<0.05). FP.2 and FP.5 (Poorly maintained fishponds) that had fifty four percent (54%) and thirty six percent (36%) respectively of the mosquito larvae captured was classified as the most highly preferred breeding habitat (mean number of larvae per dip = 0.63 and 0.42 respectively.

Pearson correlation indicated that temperature; dissolved oxygen concentration, electrical conductivity, pH, and turbidity do not necessarily influence mosquito larvae abundance in fishponds. Much as they play some role, other factors like vegetation cover, type of feed, and pond depth play a major role. Poorly maintained fishponds were the principal larvae habitants and proper management of these habitats throughout the year would have an impact on mosquito abundance.