Spatio-temporal distribution of tsetse fly trap catches in Ethiopia

Abstract: The paper deals with tsetse fly (Diptera: Glossinidae) spatial distribution and aims atimproving the methodology for precision targeting interventions in an adaptive pest managementsystem using attractive traps. In Ethiopia, as vector of trypanosome pathogens on livestock, tsetseflies play a crucial role in limiting agricultural production, both directly on food source fromanimal products and indirectly on animal traction as a source of energy. Monoconical traps,baited with cow urine as attractant, were deployed in a 20km2 area at Ethiopia’s Keto site. Thespatio-temporal distribution of Glossina morsitans submorsitans Newstead, and Glossinapallidipes Austen, was analyzed with the Spatial Analysis by Distance Indices methodology(SADIE) focusing on clustering and spatial association between-species and between-sexes. Bothspecies displayed an aggregated distribution characterized by two main patches in the south andan extended gap in the north of the monitored area. Spatial patterns were positively correlatedand stable in most cases, with the exception of the early dry season and the short rainy season,when there were differences between the species and sexes. The spatio-temporal dynamic isexplained by interacting environmental variables including climate, habitat features and cattlehost availability. For precision targeting interventions, the here presented methods are effectivefor identifying and delimiting hot spots on maps. In addition, more the improved knowledge onhot spot occurrences allows a better delimitation of the territory for control operations and a moreprecise computation of the number of traps used for monitoring and control purposes.