SINCE RECENTLY massive swarms of locusts have been threatening agricultural production and livelihood across South Asia, Africa and the Middle East. These regions which are battling the global Covid-19 pandemic like the rest of the world – have now to deal with locust invasion which is very damaging to their farmland crops.
In India, desert locusts have ravaged around [ihc-hide-content ihc_mb_type=”show” ihc_mb_who=”2,3,5″ ihc_mb_template=”1″ ] 35,000 hectares in seven heartland states, threatening cash crops as well as vegetable and pulse crops and grains.
“Yesterday the locust landed in my farm at around 5 pm. I removed the silencer of my tractor to make noise and ran the engine to drive away the locusts. I burst firecrackers too. Nevertheless the locusts devoured my vegetable and young cotton crops and inflicted damage,” says Balwinder Kang, a farmer from Tamil Naidu, speaking to Ravichandran Vanchinathan, a director of Global Farmer Network.
The migratory insects also destroyed hundreds and thousands of acres of crops in East Africa.
“The locusts have destroyed all of our grazing land, and I am very worried that my livestock will starve and die because these locusts are everywhere and are taking over the whole area,” Abdulah Hassan, a herdsman in Somalia, told Business Insider, recently.
According to the Food and Agriculture Organisation (FAO), if not controlled, desert locusts can damage food supplies and cause famine. Some 45 million sq km of cultivated land in 90 countries are potentially prone or under the threat of invasion by the desert locusts.
In order to control locusts swarms, researchers studied locusts motion behaviour using mathematical modelling.
“By using mathematical modelling, we managed to show that a locust in a swarm must be able to interact with at least two neighbours simultaneously. Without those two neighbours, the insects can’t reproduce the striking spontaneous changes in direction we are used to seeing in flocks of starlings, schools of fish – and swarms of locusts,” said Christian Yates, a mathematician from the University of Bath.
They observed on how locust swarms can be so stable. By watching locusts move around a ring, they identified some interesting behaviour.
According to Yates, small numbers of locusts move around the ring at random, but larger groups start to march together in the same direction. These groups will then spontaneously switch to march in the other direction. The more locusts in a group the longer the time interval between switches and the more stable the swarm.
The researchers then reproduced the locusts behaviour in a mathematical model and discovered that locusts move more randomly when they don’t have near neighbours. So, forming a swarm is all about neighbours.
“But that doesn’t make it “neighbourly” or friendly. The reason locusts pay so much attention to their neighbours is that locusts are cannibals! They eat each other to get the protein and salt they need.” Yates added.
In order to break up the locusts swarms apart, the study suggested using low-flying planes which will create atmospheric disturbance to disrupt locusts. But the huge size of swarms, make this method impractical. However, there will be better ways to break up swarms using similar methods with further research.
Previously, management strategies have typically focused on creating exclusion zones by burning tyres, catching them in nets or digging trenches. These localised preventive measures will prevent locusts from reaching a particular area, but can do little to halt the progress of the swarm.
The most commonly used method is by using insecticide to control locusts swarms.
“Aerial spraying of insecticides is one option, but they had no forewarning about the flight path. The spray must be done after 7.30 pm. Drone is one option, but not enough drones. As the pay load of drone is about 15-17 kg, we need more drones. If some corporates having these special kinds of drones provide them on lease they would be of immense help,” says Balwinder.
Sprayed from land or aerial vehicles, whole swarms can be targeted in relatively short periods of time. However, this has obviously led to some environmental concerns.
However, one of the most effective ways to avoid the devastating effects of locust plagues is to prevent them from happening in the first place.
Now, NASA scientists are studying how environmental changes affect locust populations by using Earth-observing satellites. By combining satellite data with information about where, when and why locust swarms emerge, they can stop the outbreaks before they start.
Long haul
The Director-General of the Food and Agriculture Organization of the United Nations (FAO), QU Dongyu, has warned that efforts to control Desert Locusts will take time, noting increased concern for the Sahel and Southwest Asia regions are adding to the burden of efforts ongoing in the Horn of Africa and Yemen.
Qu was joined by the UN Under-Secretary General and Emergency Relief Co-ordinator, Mark Lowcock, at a virtual briefing for FAO Members, regional organizations, partners, and other stakeholders as FAO raised its locust appeal to $311.6 million.
“Our gains have been significant, but the battle is long and is spreading to new areas,” Qu said. “It is clear that we cannot declare victory yet. Upsurges of this magnitude are rarely defeated in a few months.”
Qu welcomed the World Bank Group’s establishment of a $500 million programme to help countries in Africa and the Middle East combat the impact of locusts and appealed for additional support from other donors and partners.
Despite control operations, recent heavy rains have created ideal conditions for the pest’s reproduction in several countries. Young juveniles will become voracious adults in June just as farmers begin to harvest, compounding an already bleak food security situation.
“The locusts, combined with the impacts of COVID-19, could have catastrophic consequences on livelihoods and food security,” Qu emphasized.
Forecasts from the recently-released Global Report on Food Crises indicated that more than 25 million people will experience acute hunger in Eastern Africa in 2020, and an additional 17 million in Yemen. The COVID-19 pandemic will likely further undermine food security.
FAO rapidly supported governments in scaling up control activities in January and is launching an urgent appeal to support ten countries to contain the upsurge and anticipate devastating impacts on livelihoods and food security.
According to estimates, thanks to the campaigns carried out, some 720, 000 tonnes of cereal to have been saved so far — by preventing the locusts’ spread and damage to many more hectares – enough to feed five million people for a year. The livelihoods of an additional 350 000 pastoral households were also spared.
Qu stressed it was not only the short-term that mattered, but medium and long-term action to support governments and regional authorities to build capacity to anticipate, prepare and prevent future outbreaks.
In the coming months, Desert Locusts will continue breeding in Ethiopia, Kenya and Somalia. New swarms will form in June and migrate to the Sudan through South Sudan and pose a risk to the Sahel in West Africa.
There is also an increased risk along both sides of the Indo-Pakistan border, where outbreaks in the Islamic Republic of Iran, and Pakistan are still ongoing.pd[/ihc-hide-content]
