Migratory locust (Locusta migratoria) — overview, biology, and impact

Biology and behaviour

Like other locusts, the migratory locust undergoes incomplete metamorphosis: eggs hatch into wingless nymphs (called hoppers), which pass through several instars before becoming winged adults. Crowding and repeated tactile stimulation trigger physiological and behavioural changes known as phase polyphenism. In the gregarious phase individuals become more active, tolerant of one another, change in colour and form cohesive marching or flying swarms capable of long-distance movement.

Lifecycle and key characteristics

• Eggs: laid in soil in pods; development influenced by temperature and moisture.
• Hoppers: wingless, often form bands that consume local vegetation.
• Adults: capable of sustained flight and directed migration; sexes are separate.

Distribution, subspecies and taxonomy

The species has a broad native range that includes much of Africa (Africa), Asia (Asia), Australia (Australia) and New Zealand (New Zealand). It was formerly common in parts of Europe (Europe) but is now rare there. Because the species occupies diverse ecological zones, many regional forms and subspecies have been described; taxonomists do not always agree on which of these constitute valid subspecies, so some classifications remain unsettled.

Economic importance and management

Migratory locusts can cause substantial crop loss when they form swarms feeding on cereals, forage and other vegetation. Management approaches combine surveillance, early warning, and control. Typical measures include targeted application of insecticides, biological agents (such as fungal pathogens) in some settings, habitat management to reduce breeding sites, and coordinated regional monitoring. Because swarms can cross borders, international collaboration and timely data-sharing are important to limit outbreaks.

Notable distinctions and facts

The name "locust" is applied to several unrelated grasshopper species that display similar gregarious and migratory behaviour; the migratory locust is one prominent example. Its wide distribution, dramatic phase shifts, and historical role in agriculture have made it a model organism for studies of behavioural ecology, population dynamics and pest management.

For further basic information and regional details see resources linked above or specialist pest-management literature; research and monitoring continue to refine knowledge of subspecies boundaries, migratory patterns and effective control methods.