defined area to monitor and defend without locust invasions from elsewhere. In Central and Southern Africa, the service is provided by the International Locust Control Organization for Central and Southern Africa. In West and Northwest Africa, the service is co-ordinated by the Food and Agriculture Organization's Commission for Controlling the Desert Locust in the Western Region, and executed by locust control agencies belonging to each country concerned. The FAO also monitors the situation in the Caucasus and Central Asia, where over 25 million hectares of cultivated land are under threat. In February 2020, in an effort to end massive locust outbreaks, India decided to use drones and special equipment to monitor locusts and spray insecticides. Control Historically, people could do little to protect their crops from locusts, although eating the insects may have been some compensation. By the early 20th century, efforts were made to disrupt the development of the insects by cultivating the soil where eggs were laid, collecting hoppers with catching machines, killing them with flamethrowers, trapping them in ditches, and crushing them with rollers and other mechanical methods. By the 1950s, the organochloride dieldrin was found to be an extremely effective insecticide, but it was later banned in most countries because of its persistence in the environment and its accumulation in the food chain. In years when locust control is needed, the hoppers are targeted early by applying water-based contact pesticides from tractor-based sprayers. This is effective but slow and labour-intensive; a preferable method is spraying concentrated insecticide from aircraft over the insects or vegetation. The use of ultralow-volume spraying of contact pesticides from aircraft in overlapping swathes is effective against nomadic bands and can be used to treat large areas of land swiftly. Other modern technologies for planning locust control include GPS, GIS tools, and satellite imagery with rapid computer data management and analysis. A biological pesticide to control locusts was tested across Africa by a multinational team in 1997. Dried fungal spores of a Metarhizium acridum sprayed in breeding areas pierce the locust exoskeleton on germination and invade the body cavity, causing death. The fungus is passed from insect to insect and persists in the area, making repeated treatments unnecessary. This approach to locust control was used in Tanzania in 2009 to treat around 10,000 hectares in the Iku-Katavi National Park infested with adult locusts. The outbreak was contained without harm to the local elephants,