Desert Locust, Schistocerca gregaria Forskål (Orthoptera: Acrididae) Plagues

Normally, the desert locust, Schistocerca gregariaForskål (Orthoptera: Acrididae), is a solitary insect that occurs in desert scrub regions of northern Africa, the African Sahel, the Arabian Peninsula, and parts of western Asia to western India. Each locust is 7–8 cm in length, weighs about 2 g, and undergoes five molts after emerging from egg pods deposited several cm beneath the soil (preferably sandy) surface. The adult is a faded tannish yellow with wings that are mottled with black blotches. During the solitary phase, desert locust populations are low and present no economic threat to agriculture. After periods of drought, when vegetation flushes occur in major desert locust breeding areas, rapid population buildups and competition for food occasionally result in transformation from solitary phase to gregarious behavior on a regional scale. Following this transformation, which can occur over two or three generations (there are generally three to five generations per year),...