The Red–billed quelea is a small African weaver finch of the family Ploceidae, weighing about 20g. It is the most numerous and destructive bird pest of small seeded cereals in Sub-Saharan Africa. Quelea birds frequently form large breeding colonies or night roosts, with populations ranging from a few thousand to millions of birds. In general, the birds breed 2-3 times a year during and just after the rainy seasons. They inflict serious damage to small grains such as sorghum, wheat, millet, rice, barley, teff and oats; particularly when their natural food of grass seeds is either seriously depleted or difficult to obtain. In Africa, it is the most important avian pest of small grain crops causing damage equivalent to US$ 88.6 million per annum (2018 average cereal prices) throughout semi-arid zones.
Quelea outbreaks occur annually along the Rift valleys of Ethiopia. They start in the Southern Region in May and June after initial breeding in March and then proceed to the central rift valley areas from August to September. They finally migrate to the Northern rift valley in about October and feed on rain-fed crops until the end of November.
The pest if not controlled can inflict serious damage on rain-fed small cereals like teff, wheat, sorghum, and barley, and wheat; the primary staple foods of the country. Since 2020, due to the wheat import substitution program, irrigated wheat is being cultivated over vast areas in four Administrative Regions in an effort to meet the national wheat demand. A number of farmers have embraced the program and as a result, the quelea control operations are continuous throughout the year.
During the 2022 main rain season quelea bird outbreaks occurred in Oromia, Amhara and Afar Administrative Regions. The Desert Locust Control Organization for Eastern Africa (DLCO-EA) deployed spray aircraft for quelea bird aerial control in Amhara and Afar Administrative regions from mid-October to the end of November 2022.
During the control operation, approximately 62.9 million quelea birds in 37 roosts covering 550 ha were killed using 1,100 litres of Bathion 640 g/l ULV. The estimated kill for the operation ranged from 80 to 90 percent in the different control sites. The DLCO-EA aerial control operation saved Ethiopia and the region 15,725 tons of grain, equivalent to US$17,454,750.