Investigations were carried out in the upper Didessa river valleyrnto determine the preference of Glossina morsitans 6ubmoritansrntowards available hosts, trap design, and odour bai ts. Biconicalrntrap baited with either acetone, octenol or cow urine or all thernthree put together in different container was more effective inrncatching Glossina morsitans submorsians than the Ngu trap underrnthe same experimental setup. Among odour attractants testedrnseparately, acetone appeared to be more potent in attractingrntsetse flies than octenol and cow urine. On the other hand, Ngurntrap was superior than biconical trap in catching tsetse fliesrnwhich had residual blood in their gut. Cow urine kept in arncontainer for some days increased the catches of the flies whenrncompared with the freshly collected urine. A low infection raternof 2.6% was detected in Glossina morsitans submorsitans of thernupper Disease river valley. On the other hand the prevalence ofrnanimal trypanosomiasis on the edge of the escarpment was veryrnhigh (42.6%). TÂ£YD9nOsQ~~_ cOQg9lense was the dominant speciesrnidentified in both the tsetse flies and in the cattle of thernlocality. Enzyme Linked Immunosorbent Assay (ELISA) test wasrnemployed to see the rate of digestion of blood proteins ingestedrnby teneral and non-teneral laboratory reared Q.m. submorsitans .rnat different time intervals after feeding. This test showed thatrnthe non-teneral tsetse digestcd the species distinguishingrnbloodmeal components faster than the tenerals- at 48hr postrnfeeding, the bloodmeal donor was identifiable in 87.5% of thernteneral tsetse and 55.5% of non-teneral tsetse flies. The sourcernof the bloodmeals from 160 fed Q.m. submorsitans captured in thernvalley were identified by ELISA test. Accordingly warthogrnaccounted for 28.8% of meals, whereas human and buffalo bloodrnaccounted for 11.9% and 6.9% of the meals, respectively. Othersrnlike the giraffe, goat, cattle and elephant accounted for a veryrnlow percentage of flies' bloodmeal. Thus the warthog appeared tornbe the major maintenance host for .a.!!l. submorsitans in thernstudy area. Sex composition of the catches and the efficiency ofrneach bait system as well as the results of the blood mealrnanalysis are discussed.