Adult Zygoptera of Kibale National Park, Uganda: habitat associations and seasonal occurrence

In this study, a 10-month survey of four aquatic sites in Kibale National Park, Uganda was used to quantify seasonal and spatial variation in both limnological features of the sites and adult damselfly assemblage structure. Of the 4 limnological characters measured dissolved oxygen was the most variable among sites, ranging from an average of 1.01 mg I1 in the interior of the Rwembaita Swamp (a papyrus-dominated wetland) to 6.71 mg I’1 in an inflowing tributary of the swamp. Species richness was similar among sites and did not correlate with dissolved oxygen concentration. However, site was a significant predictor of occurrence for some spp. This suggests that site effects are important, and that a combination of site-specific environmental characters may underlie the observed distributional patterns. Seasonal fluctuation in rainfall was not a good predictor of Zygoptera activity. Several spp. were active in both the wet and dry seasons. Surprisingly, adult Proischnura subfurcatum were detected year-round in the hypoxic waters of the Rwembaita (papyrus) Swamp and did not occur at any other sites in the larval or adult phase, suggesting that this sp. is a swamp specialist.