Red-billed quelea is sometimes called "Africa's feathered locust". The usual pest-control measures are spraying avicides or detonating fire-bombs in the enormous colonies during the night. Extensive control measures have been largely unsuccessful in limiting the quelea population. When food runs out, the species migrates to locations of recent rainfall and plentiful grass seed; hence it exploits its food source very efficiently. It is regarded as the most numerous undomesticated bird on earth, with the total post-breeding population sometimes peaking at an estimated 1½ billion individuals. It feeds in huge flocks of millions of individuals, with birds that run out of food at
Red-billed quelea during daylight hours. The governments of Botswana, Ethiopia, Kenya, South Africa, Sudan, Tanzania, and Zimbabwe have regularly made attempts to lessen quelea populations. The most common method to kill members of problematic flocks was by spraying the organophosphate avicide fenthion from the air on breeding colonies and roosts. In Botswana and Zimbabwe, spraying was also executed from ground vehicles and manually. Kenya and South Africa regularly used fire-bombs. Attempts during the 1950s and '60s to eradicate populations, at least regionally, failed. Consequently, management is at present directed at removing those congregations that are likely to attack vulnerable fields. Red-billed quelea