THE LOCUS ATTACK

 The desert locust (Schistocerca gregaria) is a short-horned grasshopper

These winged insects differ from normal hoppers, and become dangerous only when their populations build up rapidly and the close physical contact in crowded conditions triggers behavioural changes.

The normal breeding season for locusts in India is July-October. But this time, they have been sighted by mid-April.

Locusts are polyphagous, i.e. they can feed on a wide variety of crops. Secondly, they have an ability to multiply rapidly. A single female desert locust lays 60-80 eggs thrice during its roughly 90-day life cycle.

the Mekunu and Luban cyclonic storms of May and October 2018 that struck Oman and Yemen, respectively. These turned large desert areas in remote parts of the southern Arabian Peninsula into lakes, which allowed the insects to breed undetected across multiple generations.

The main locust breeding areas in the Horn of Africa, Yemen, Oman, Southern Iran and Pakistan’s Baluchistan and Khyber Pakhtunkhwa provinces recorded widespread rains in March-April.

East Africa, in fact, had its wettest rainfall season in over four decades even during October-November

Strong westerly wind currents were consistent during this period was also helped them migrate to India. 

Four species of locusts are found in India: Desert locust (Schistocerca gregaria), Migratory locust (Locusta migratoria), Bombay Locust (Nomadacris succincta) and Tree locust (Anacridium sp.).

The desert locust is regarded as the most destructive pest 

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, according to the PPQS.

four chemicals — Melathion 50% EC, Melathion 25% WP, Chloropyriphos 20% EC and Chloropyriphos 50% EC — that must be diluted in water and used as pesticides and sprayed in the evening to control the swarm.

Covering plants with polythene can also counter-productive during this heat.

Why has the chain not been broken even after 80 years?

there are 30 countries in four regions of different continents that have an arid climate with large deserts that provide an ideal breeding ground for the locust

We have four commissions for these 30 countries including the Commission for Controlling the Desert Locust in NorthWest Africa (CLCPANO), Commission for Controlling the Desert Locust in Western Region (CLC PRO), Commission for Controlling the Desert Locust in Central Region (CRC) and Commission for Controlling the Desert Locust in Southwest Asia (SWAC) which includes Iran, Pakistan, Afghanistan and India 

A burgeoning locust swarm in Rajasthan, Gujarat and even parts of Madhya Pradesh threatens to amplify into an agrarian disaster

 

There were 13 locust upsurges from 1964 to 1997, and after 2010 there was “no large scale breeding” reported.

 Once a significant outbreak starts, it lasts for about two years, and then there is a quietus for about eight years 

The East Punjab Agricultural Pests, Diseases and Noxious Weeds Act, 1949, has a provision whereby a District Collector can “...call upon any male person not below the age of 14 years resident in the district to render all possible assistance ...” and there is potential imprisonment for failure to abide by the law.

The breeding locusts which threaten farming are an indirect fallout of the warming Indian Ocean, as some meteorologists suggest.

Last year it was  a positive Indian Ocean Dipole, or relatively higher temperature in the western Indian Ocean, led to record-breaking rainfall in India as well as in eastern Africa. But moist African deserts precipitated locust breeding and favourable rain-bearing winds aided their transport towards India.

routine coordination activities involving India, Pakistan and Afghanistan regarding spraying pesticides were halted.

The locust invasion, which started from the India-Pakistan border on April 11, has affected about 20 of 33 districts in Rajasthan, after the insects crossed the Thar desert and travelled far in search of food, taking advantage of favourable wind conditions with the onset of summer.

The U.N. Food and Agriculture Organisation had recently warned that locusts were breeding in large numbers in Sudan and Eritrea on Africa’s Red Sea Coast as well as in Iran. They have been travelling through Pakistan to enter the Indian side of Thar desert.

Locusts can fly up to 150 km in a day, and a 1 sq. km. swarm can eat as much food as 35,000 people, in terms of weight, in a single day. 

A one square kilometre swarm, containing about 40 million locusts, can in a day eat as much food as 35,000 people, assuming that each individual consumes 2.3 kg of food per day, says the Food and Agriculture Organisation (FAO)

Immature locusts, which are not fully grown, have the capacity to cause more harm as they have a longer lifespan

The grasshoppers, which flew out from Sudan and Eritrea on Africa’s Red Sea Coast after excess rains, were earlier breeding in Iran.

The U.N. Food and Agriculture Organisation has warned of more attacks of locusts along both sides of the India-Pakistan border till early July after summer breeding

The strategies include spraying environmental-friendly neem-based pesticides, mass ground spray of malathion pesticides using tractor-mounted sprayers and fire engines, spraying bio-pesticide Metarhizium anisopliae. “Birds and poultry birds, which eat locust can be used to control the locust swarms.

These locusts can change their DNA according to the prevailing environmental situation. In the seasons of availability of adequate food, the locust multiplies their progeny faster

The Grasshopper found in Kerala recently the “coffee locusts” (Aularches miliaris) do not belong to the locust family and that they are a grasshopper species belonging to the Pyrgomorphidae family.

the locusts emerged in February 2020  from Sudan and Eritrea on Africa’s Red Sea Coast and travelled through Saudi Arabia and Iran to enter Pakistan, where they invaded the Sindh province and from there they moved into Rajasthan and Gujarat 

Swarms of locusts have appeared,boosted by cyclones that have given rise to unusual levels of rainfall and created ideal breeding conditions in remote corners of the globe like Somalia’s Puntland area, Arabia’s Empty Quarter and regions like Yemen, where war prevents effective spraying operations.

there were communication gaps between State governments and the Centre, which takes the lead in the locust fight 

even  organophosphate insecticides such as Malathion (96% ultra-low volume aerial application) are effective against locusts.

Locust hoppers are easily identifiable; the young immature adults being pink in color while the old ones become dark grey or yellow with dark purple to black mandibles.