The Effect of Breeding Habitat Characteristics on the Larval Abundance of Aedes Vector Mosquitoes (Diptera: Culicidae) in Three Localities, Galle District, Sri Lanka

Abstract

Dengue has become a national burden in Sri Lanka, and the understanding of breeding ecology of vectors, Aedes aegypti Linnaeus and Aedes albopictus Skuse, is the most effective way to control the disease. The present study was undertaken to investigate the relative larval abundance of Ae. aegypti and Ae. albopictus in different types and characteristics of containers in three selected localities in Galle district, Sri Lanka. Totally, 550 containers were positive for both Ae. aegypti and Ae. albopictus larvae. Aedes albopictus showed the high larval abundance in all studied sites. The larval abundance of artificial containers (90.57%) was high than that of natural containers (9.43%) for both Aedes spp. ( $P<0.05$ ). The breeding preference for A. aegypti was high in tires (rubber) (17.82%), while plastic cups (28.00%) were the most preferable container type for Ae. albopictus. Dark color containers than light color containers ( $P<0.05$ ) and containers with leaf litter accumulated as detritus ( $P<0.05$ ) showed high relative larval abundance for both Aedes species. Containers with 50–100 ml volume of water showed the highest relative abundance of both Ae. aegypti (29.28%) and Ae. albopictus (41.79%) ( $P>0.05$ ). The high larval abundance of Aedes recorded in ground level containers (1–5 cm) and their abundance decreased significantly with the increasing of height where containers were found (1–20 cm) ( $P<0.05$ ). The significantly high relative abundance was observed with the increase of the shady level for Ae. aegypti (57.34%) and Ae. albopictus (61.32%) ( $P<0.05$ ). This knowledge will be helpfull to implement dengue surveillance programs in the area.