Red-billed quelea parasites found in queleas include "Haemoproteus" and "Plasmodium". The red-billed quelea is caught and eaten in many parts of Africa. Around Lake Chad, three traditional methods are used to catch red-billed queleas. Trappers belonging to the Hadjerai tribe use triangular hand-held nets, which are both selective and efficient. Each team of six trappers caught about twenty thousand birds each night. An estimated five to ten million queleas are trapped near N'Djamena each year, representing a market value of approximately US$37,500–75,000. Between 13 June and 21 August 1994 alone, 1.2 million queleas were caught. Birds were taken from roosts in the
Red-billed quelea from northern and central Sudan and central Ethiopia in May and June, to breed in southern Sudan, South Sudan, southern Ethiopia and northern Kenya, moving back north from August to October. In southern Africa, the total population of the subspecies "Q. quelea lathamii" in October converges on the Zimbabwean Highveld. In November, part of the population migrates to the northwest to northwestern Angola, while the remainder migrates to the southeast to southern Mozambique and eastern South-Africa, but no proof has been found that these migration cohorts are genetically or morphologically divergent. The red-billed quelea is regarded as the most numerous