Locust attacks

Recently, locust attacks emanating from the desert area in Pakistan have struck parts of Rajasthan and Gujarat, causing heavy damage to standing crop.

• Locusts, which are part of the grasshopper family, are highly mobile insects that can migrate across different countries and cause extreme damage to crops.
• India has suffered the biggest Locust Attack in 25 Years, which is not fully controlled yet.
  • History: Although no locust plague cycles have been observed after 1962, during 1978 and 1993, large scale attacks were reported.
  • This year the first locust swarms left to Yemen, Saudi Arabia, and south-west Iran.
  • The locust department in India has blamed Pakistan for this year’s attack, saying it failed to conduct control operations successfully.
• Crop damage: Estimates say crops were affected in more than 3.5 lakh hectares in districts of Rajasthan and Gujarat.
  • Crops of mustard, cumin and wheat have been most damaged.
  • Farmers whose crop was damaged would be entitled to compensation.
• Measures India has taken: India has a locust control and research scheme that is being implemented through the Locust Warning Organisation (LWO), established in 1939 and amalgamated in 1946 with the Directorate of Plant Protection Quarantine and Storage (PPQS) of the Ministry of Agriculture.
  • LWO’s responsibility is monitoring and control of the locust situation in Scheduled Desert Areas, mainly in Rajasthan and Gujarat, and partly in Punjab and Haryana.
• International measures: Food and Agriculture Organisation (FAO) of the United Nations is the international agency that monitors and manages locust invasions.
  • All locust-affected countries transmit data about attacks to the FAO.
  • FAO also provides forecasts for locust attacks up to six weeks in advance and issues warnings for each country.

Locust facts

• From grasshopper family: Locusts are a group of short-horned grasshoppers. The word "locust" is derived from the Vulgar Latin locusta, meaning grasshopper.
• Polyphagous feeder: Locusts can eat a large variety of plants. A small swarm of the desert locust, which contains about 40 million insects, can eat on average as much food in one day as about 10 elephants, 25 camels or 2,500 people.
• Migratory: Adult locust swarms can fly up to 150 km a day with the wind. They migrate long distances in destructive swarms.
• High breeding: Under suitable conditions of drought followed by rapid vegetation growth, serotonin in their brains triggers a dramatic set of changes and they start to breed abundantly.
  • Each locust lays about 150 eggs. They multiply in numbers, and they lay eggs only in moist soil.
  • They form bands of wingless nymphs which later become swarms of winged adults.
• Origin: The swarms usually originate in the Arabian Peninsula and the Horn of Africa.
• Indian locusts: Only four species of locusts are found in India.
  • Desert locust (Schistocerca gregaria) - regarded as the most important in India as well as internationally.
  • Migratory locust (Locusta migratoria)
  • Bombay Locust ( Nomadacris succincta)
  • Tree locust (Anacridium sp.)
• Destroy plants: The swarms devour leaves, flowers, fruits, seeds, bark and growing points, and also destroy plants by their sheer weight as they descend on them in massive numbers.
• Risk: India is most at risk of a swarm invasion just before the onset of the monsoon.
  • This year the extended monsoon provided a favourable environment for the locusts to multiply.
• Plagued history: Swarms have devastated crops and been a contributory cause of famines and human migrations since prehistory. The ancient Egyptians carved them on their tombs and the insects are mentioned in the Iliad, the Bible and the Quran.
• Locust control: To control locust swarms, a chemical called organophosphate is sprayed in small, concentrated doses.