Locust Attack In India

Topics Covered

  • Why In News? 
  • What Are Locusts? 
  • Ten Prominent Species Of Locusts 
  • Which Countries Are Affected? 
  • Relationship Between Locusts And Climate Change 
  • Previous Locust Attacks In India 
  • Role Of The United Nations In Locust Control
  • India’s Response To Locust Swarms 
  • Controlling Locusts 

 

Why in news?

  • In recent weeks, locust swarms have attacked crops in more than a dozen countries in Asia and Africa.
  • The United Nations have announced that the situation is extremely alarming in three regions – the Horn of Africa, the Red Sea area, and southwest Asia.
  • The Horn of Africa being the worst-affected area.

What are locusts?

  • The desert locust (Schistocerca gregaria) is a short-horned grasshopper.
  • Solitary phase – In “solitary phase”, these winged insects are safe.
  • They become dangerous only when their populations build up rapidly.
  • Close contact in crowded conditions trigger behavioural changes.
  • Gregarious phase – They enter the “gregarious phase”, by grouping themselves into bands and forming swarms.
  • They travel great distances (up to 150 km daily), while eating up every bit of vegetation on the way.
  • If not controlled at the right time, these insect swarms can threaten the food security of countries.
  • At present countries in the Horn of Africa such as Ethiopia and Somalia are witnessing one of the worst locusts attacks in the last 25 years.

Ten Prominent Species Of Locusts

  • Desert Locust
  • Bombay Locust
  • Migratory Locust
  • Italian Locust
  • Moroccan Locust
  • Red Locust
  • Brown Locust
  • South American Locust
  • Australian Locust
  • Tree Locust

In India, out of these ten locusts, only four are reported (along with their scientific names)

  • Desert locust – Schistocerca gregaria
  • Migratory locust – Locusta migratoria
  • Bombay Locust – Nomadacris succincta,
  • Tree locust – Anacridium sp

Which countries are affected?

  • The Food and Agriculture Organisation (FAO) of the United Nations has currently identified three hotspots of threatening locust activity, where the situation has been called “extremely alarming” — the Horn of Africa, the Red Sea area, and southwest Asia.
  • The Horn of Africa has been called the worst-affected area, where the FAO has said there is “an unprecedented threat to food security and livelihoods”.
  • Locust swarms from Ethiopia and Somalia have travelled south to Kenya and 14 other countries in the continent.
  • In the Red Sea area, locusts have struck in Saudi Arabia, Oman, and Yemen.
  • In southwest Asia, locusts swarms have caused damage in Iran, India, and Pakistan.
  • Pakistan and Somalia have recently declared locust emergencies.

Relationship Between Locusts And Climate Change

  • During quiet periods—known as recessions—desert locusts are usually restricted to the semi-arid and arid deserts of Africa, the Near East and South-West Asia that receive less than 200 mm of rain annually.
  • In normal conditions, locust numbers decrease either by natural mortality or through migration.
  • However, the last five years have been hotter than any other since the industrial revolution and since 2009.
  • Studies have linked a hotter climate to more damaging locust swarms, leaving Africa disproportionately affected—20 of the fastest warming countries globally are in Africa.
  • Wet weather also favours multiplication of locusts. Widespread, above average rain that pounded the Horn of Africa from October to December 2019 were up to 400 per cent above normal rainfall amount.
  • These abnormal rains were caused by the Indian Ocean dipole, a phenomenon accentuated by climate change.

Previous Locust Attacks In India

  • The first swarms were sighted along the India-Pakistan border on 11th April 2020, months ahead of the usual time of arrival.
  • Agriculture Ministry’s Locust Warning Organization (LWO) reported the first sightings in Rajasthan’s Sri Ganganagar and Jaisalmer districts.
  • In India, locusts are sighted normally during July- October along the Pakistan border.
  • In 2019, parts of Western Rajasthan and Northern Gujarat reported swarms that caused damage to growing rabi crops.
  • These were the first swarms reported in India since 1997.

Role of the United Nations in Locust Control

  • The United Nations’ response to locust attack control is multi-agency in nature. While the immediate sector at risk is food security, climate change plays an exacerbating role.
  • One of UNEP’s roles is to disseminate the latest science on emerging climate trends to inform cross-sectorial policies and ensure resilience is built in the relevant sectors.
  • The role of the World Meteorological Organization is to forecast the more immediate weather changes that may exacerbate the locusts’ attacks.
  • The World Health Organization’s role is to classify potential risks of different chemical agents to enable governments to invest in the safest one.
  • One of the mandates of the Food and Agricultural Organizations is to provide information on the general locust situation and to give timely warnings and forecasts to those countries in danger of invasion. The organization operates a centralized desert locust information service.

India’s Response to Locust Swarms

  • Locust Watch Centres are warning farmers of the speculated movement of the locust swarms. Also, the use of organophosphate chemicals with ultra-Low volume sprayers is a method to control the locust swarms attack. ‘Chlorpyriphos’ is being reserved in certain cities as it is effective in controlling a variety of insects following ministries are keeping the charge of the locust attacks:
    • Ministry of Agriculture and Farmers Welfare, Department of Agriculture, Cooperation and Farmers Welfare
    • Ministry of External Affairs
    • Ministry of Home Affairs
    • Ministry of Defence
    • Ministry of Earth Sciences
    • Ministry of Civil Aviation and
    • Ministry of Communications
  • The role of stakeholders like State Governments, State Health Department and farmers, is equally important. The government is making use of drones to track the locust swarms movements. The other things used to contain the attack are:
    • Satellite-derived tools
    • Special fire-tenders and
    • Sprayers at pre-identified border locations

Controlling locusts

  • Controlling desert locust swarms primarily uses organophosphate chemicals by vehicle-mounted and aerial sprayers, and to a lesser extent by knapsack and hand-held sprayers.
  • Extensive research is ongoing regarding biological control and other means of non-chemical control with the current focus on pathogens and insect growth regulators. Control by natural predators and parasites so far is limited since locusts can quickly move away from most natural enemies.
  • While people and birds often eat locusts, this is not enough to significantly reduce population levels over large areas.