Even as India struggles to emerge from the economic cost of the lockdown owing to the Corona virus pandemic, a blizzard of devastating bugs—Locusts--descend from the skies. They are a farmer’s worst nightmare. Bearing in mind that an adult Locust can eat its entire body weight every day, it's hardly surprising that a huge swarm measuring several miles wide will devour everything in its path.
Farmers in several states in India like Gujarat, Rajasthan, Maharashtra, Madhya Pradesh, Punjab, Haryana and Uttar Pradesh now fear widespread crop losses if these fast-spreading locusts swarm are not brought under control before the arrival of the monsoon rains—which spurs sowing of rice, sugarcane, cotton and other summer crops in the country.
Last year in December Indian states of Gujarat and Rajasthan, had reported locust infestations. So far locust swarms have been recorded in close to 50,000 hectares in Rajasthan and Madhya Pradesh and if these swarms continue to increase as the monsoon arrives, it can cause serious damage to crops. In fact, locust invasion this year in India is regarded as the worst in 27 years!
A crucible of ideas
Frustrated farmers have begun banging plates in several villages; some are blowing whistles and some are even seen throwing stones to scare the locusts away. Other farmers have resorted to lighting fires to smoke locusts out of trees on streets, in fruit orchards and in the fields.
Experts claim that the locusts swarms were pulled eastwards by the strong westerly winds that accompanied Cyclone Amphan.
The swarm travels with the wind, it’s the most energy saving way to fly. As for the cyclonic winds, it has moved from Rajasthan into Madhya Pradesh. The insects too are expected to move east as far as Bihar and Orissa until July, and then return westwards on changing monsoon winds.
Locusts swarms are expected to move east towards Bihar and Orissa untill July, then returning westwards when monsoon winds change direction.
Locusts have begun devastating crops in India's heartland. This region is already struggling with economic cost of corona virus lockdown
Experts fear that locust attack may be worse this year in India owing to a chain of climate events and the difficult circumstances owing to the Covid-19 pandemic, where the administrative machinery is already exhausted handling issues related to the lockdown, migrant movement and managing the logistics of supplies.
The current invasion of desert locust originated along the Red Sea, in Yemen and Oman, during the 2018 to 2019 winter. Locust swarms were reported this year in some cities like Jaipur, MP’s Gwalior, Morena and Sheopur, and recently stray swarms in Maharashtra’s Amravati, Nagpur and Wardha and is now moving towards the Southern parts of India.
A locust attack alert has been sounded in old united Adilabad and Nizamabad districts by the Central Integrated Pest Management Centre in Hyderabad. Individual locusts as pest in crop were seen in early January in some polyhouse raised horticulture crops in Adilabad but the destruction is much higher this time.
Thousands of locusts invade Jaipur city in Rajasthan on May 25 (scroll.in)
Locust invasion in Jaipur city ( courtsey SC Amritsar on YouTube)
Picture of desert locusts (Representational)
Uttar Pradesh and MP
With the desert locusts having begun to arrive in Jhansi the Prayagraj district administration in UP has begun preparations. “The swarm of the locust is expected to spoil the crops and trees of the region to a great extent. In the wake of possible locust attack in the city, we have tested the machines and now we are prepared to deal with it,” ANI news agency quoted Ajay Kumar Sharma, member of the team fighting against the locust attack.
In Jhansi district, however, where locusts had swarmed thrice in the past one week, an agriculture department official told PTI news agency that widespread spraying of pesticides has helped the district administration in containing the threat and that the swarms have scattered.
“They locust swarms have now begun moving towards neighbouring areas of Madhya Pradesh flying in the direction of the wind. Because of moisture in the air and wind speed, the swarm is likely to further scatter from Shivpuri in Madhya Pradesh to Lalitpur in Uttar Pradesh. A swarm of 1.5 km was in Rajasthan’s Alwar and it can move towards Bhangarh, Tonk, Sawai Madhopur an anonymous official was quoted in a story by the newspaper Indian express.
Farmers on the Maharashtra-Gujarat border have upped vigil, especially during night, on their fields for a potential locust attack. Desert locusts recently swarmed into Chikhaldara, Morshi, Warud, Katol, and Ramtek areas in the Vidarbha region. In the latest update, locusts are expected to enter the areas adjacent to the Gujarat border, like Palghar, from the neighbouring state.
State Agriculture Minister Dadasaheb Bhuse, was quoted in an Indian Express story on June 2, where he said a swarm of locusts had entered the Amravati district from Madhya Pradesh on May 24, but the agriculture department and farmers managed to initiate quick measures to destroy them.
Swarms of a desert locust have begun destroying banana, rubber and other crops in parts of plantation-dominated districts of the Nilgiris in Tamil Nadu. Farmers in Poovankodu and Viyanur have already begun reporting on the locust invasion. Farmers in Kanyakumari district bordering Kerala also claimed that locusts had affected the banana and rubber crops.
However, the state government on May 30, 2020 said these were native grasshoppers and not the desert locusts. It advised the farmers to use bio insecticide like neemseed oil to protect agriculture and horticulture crops. An expert committee from the Tamil Nadu Agriculture University undertook an inspection in Nilgiris and Krishnagiri districts and found that the species which affected the crops in the districts in the Western Ghats region were local grasshoppers.
However, as a precaution, the collectors of Theni, Coimbatore, Tiruppur, Erode, Thirupattur, Nilgiris, Kanyakumari and Tenkasi, most of which bordering neighbouring states, have been directed to maintain a vigil and take appropriate preventive measures.
The locust swarmed into Andhra Pradesh on May 28, 2020 destroying planted crops in Dasappa Road, Rayadurga in Anantapuram district. The state administration expects that the desert locusts may move towards central coastal Andhra Pradesh from Krishna and West Godavari districts as on June 2, 2020.
A report in The Hindu, quoting an agrometeorologist from the Agriculture Research Station at Rekulakunta in Anantapur, said desert locusts would move towards Krishna and West Godavari districts after touching the Karimnagar, Jagityal and Nalgonda areas in Telangana going by present indications such as wind direction. While a locust invasion has been ruled out in the districts of Anantapur, Kadapa or Chittoor, some places in Kurnool might be affected.
*In its update on 2 March, the FAO’s locust watch service claimed that the threat from locusts currently remains high in East Africa, parts of the Middle East and Pakistan. It had also warned of large increases in locust numbers in the coming months. Parts of East Africa including Kenya and Somalia could see 400-fold increases in swarm sizes by June as the insects reproduce once again. The map here, provided by the FAO locust service, shows where insect numbers are likely to increase between March and June. (source : www.carbonbrief.org ) click on the map to go to source.
Desert locust recession area (where solitary locusts persist in the central, drier parts) of the species with seasonal breeding zones and population movements between them (click on map for source)
The unprecedented Desert Locust threat to food security and livelihoods continued in the Horn of Africa and is likely to spread to southwest Asia and perhaps West Africa.
EAST AFRICA & YEMEN
In East Africa, second-generation breeding is underway in northwest Kenya and numerous hopper bands have formed that will give rise to immature swarms from the second week of June until at least mid-July. A similar situation is underway in Somalia and Ethiopia. Control operations continue in all affected areas. Most of the new swarms will migrate northwards from Kenya to Ethiopia and traverse South Sudan to Sudan after mid-June while other swarms will move to northern Ethiopia. Swarms that reach northeast Somalia are likely to migrate across the northern Indian Ocean to the Indo-Pakistan border area. In Yemen, breeding is in progress along the southern coast and in the interior where swarms are likely to form, some of which could migrate to northern Somalia and northeast Ethiopia.
Control operations continue in spring breeding areas of Iran and Pakistan. Early migration of spring-bred swarms from southwest Pakistan to Rajasthan, India occurred in May before the monsoon and some swarms continued to northern states for the first time since 1962. The swarms will oscillate east and westwards before returning to lay eggs with the onset of the monsoon in Rajasthan where successive waves of swarms will arrive from southern Iran in June and the Horn of Africa in July. Control operations are underway.
In Sudan, the seasonal rains commenced recently in the extreme south of the summer breeding area just north of South Sudan. If rains continue in the coming weeks, then conditions are likely to be favourable for any swarms that arrive from Ethiopia and Kenya and they would be more likely to settle, mature and lay eggs. If, on the other hand, rains are limited and conditions remain dry during June in Sudan, then swarms would continue to eastern Chad in the last week of June and migrate further west in the Sahel of West Africa ahead of the summer rains, reaching eastern Niger during the first week of July, eastern Mali in mid-July, southeast Mauritania in late July.
Locusts by the billions have begun descending on parts of Kenya--the worst outbreak in 70 years. Small planes laden with pesticides are spraying over affected areas, which according to experts is the only way for effective control.
Somalia’s ministry of agriculture on Sunday declared a national emergency and a major threat to the country’s food security. The statement said that the “uncommonly large” locust swarms are consuming huge amounts of crops.
Locusts swarms, the size of major cities, the locusts have also affected parts of Sudan, Djibouti and Eritrea, whose agriculture ministry has claimed that both the military and general public have been deployed to combat them.
The swarms are also heading towards the breadbasket of Ethiopia, the second major populous country in the African continent, in what is being considered as that nation’s worst outbreak in 25 years. On June 4, last week startled residents of Ethiopia’s capital, Addis Ababa, began reported sightings of the insects.
The insects have also invaded India and Pakistan, where the government declared a national emergency. Favorable weather conditions and a delayed government response have helped the locusts breed and attack crop areas. Their potential for large-scale destruction is raising fears of food insecurity.
East Africa is facing large swarms of locust, especially in countries like Kenya and Ethiopia. This has resulted in the loss of thousands of acres of standing crops. One statistic claims that locusts swarms are destroying enough food per day that was to feed 35,000 people.
Numbers gathered by United Nations claim that Kenya is experiencing the worst desert locust infestation in 70 years, while Ethiopia and Somalia haven’t seen a plague this severe in 25 years. Swarms covering an area as large as 2,400 km2 are moving across East Africa at speeds up to 150 kilometers a day. Every one km2 locust swarm is comprised of approximately 40 million locusts, with larger swarms reaching hundreds of millions.
Even as crops and vegetation are getting wiped out by these swarms, food insecurity in East Africa is only getting worse. The United Nations, claims that 19 million people in the region are already severely food insecure, and the locust invasion can cause even more malnutrition and food scarcity issues. To combat the swarms, Kenya, Ethiopia and Somalia are spreading insecticide sprays across over 4.85 lakh hectares of land. Desert locusts breed incredibly fast, with egg pods holding roughly 80 eggs leading to about 16-20 adult locusts in as little as two months.
During the positive phase of the Indian Ocean Dipole, which typically peaks in September – November, cooler-than-normal sea surface conditions west of Indonesia and warmer-than-normal conditions in the western Indian Ocean alter the atmospheric circulation in the Indian Ocean region. Indonesia and Australia tend to be drier than normal, which increases the chances of brushfires, while eastern Africa tends to be wetter than normal, increasing the likelihood of floods. The negative phase brings the opposite pattern. (source climate.gov). Please click on map for source
Invasion area of desert locusts. (please click map for source)
Distribution of Red locusts (pls click map for source)
Distribution of Italian locusts. (please click map for source)
Scientists claim that a pattern of warming Indian Ocean can be the trigger for the present locust attack. A meteorologist may refer to this phenomenon as the Indian Ocean Dipole. Here the western and eastern parts of the ocean, warm at different levels and this tends to have an impact in inviting excessive rains to India and Western Asia.
Now within this Indian Ocean Dipole, there is something called a ‘positive’ dipole, a situation where the western part of the ocean turns hotter by a degree or more than the eastern. In 2019 meteorologists registered a strong positive dipole in the Indian neighborhood which led to a temperature difference of more than two degrees.
This positive dipole was so strong that it brought torrential rains in India last June. It was the highest that India saw in decades. These rains lasted for close to a month. This extended rainfall period was also noticed in several parts of West Asia, Oman, Yemen and in the Horn of Africa, which consists of countries like, Ethiopia, Somalia, Kenya. These extended rains caused the dry sand heavy with moisture, facilitating the locusts to breed and lay eggs and which finally lead to the formation of several locust swarms. As for the positive dipole, it had begun to take shape as late as 2018 and locust outbreaks were growing in Africa, which was also witnessed last year.
The winds helped the locust swarms to fly and breed in traditional areas like Iran, Afghanistan, Pakistan and India. The Food and Agriculture Organization (FAO), a specialised agency of the United Nations has been sending alerts on developing swarms. Somalia announced a national state of emergency due to the outbreak in February 2020, while Pakistan declared a national emergency for the second time this year, in April.
What needs mention here is that an unusually mild summer this year, which saw several bouts of rainfall over north and western India from March to May, also helped the insects breed. Normally, the locust season in India spans June to November and coincides with the kharif season.
Also some scientists have suggested extreme wet weather seen during the 2018 and 2019 dipoles could be linked to climate change. António Guterres, the UN’s secretary general, recently said in a statement: “There is a link between climate change and the unprecedented locust crisis plaguing Ethiopia and East Africa. Warmer seas mean more cyclones generating the perfect breeding ground for locusts. This is getting worse by the day.”
In a recent interview to a magazine carbonbrief.org, Dr Wenju Cai, director of the Centre for Southern Hemisphere Oceans Research at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia said, “The extreme positive dipole in 2019 certainly does fit into a picture of long-term change.”
How are locusts responding to global climate change?
Insect responses to global climate change are presently part of a numerous global studies. Insects are sensitive to climate warming. Their responses to increasing temperatures can be grouped into three major categories
Expansion of ranges,
Shifts in phenology—which is a study of cyclic and seasonal natural phenomena
Developmental rate acceleration.
For locusts the information available on effects of global climate change is scarce, and, all that exists today deals exclusively with Oriental migratory locust. Researchers in China analyzed locust outbreak records ranging over a thousand years (957AD–1956) and corresponding weather conditions in China and came to an unexpected conclusion, according to the lead author of a 2013 research paper ‘Locusts and remote sensing: a review’ written by Alexandre V. Latchininsky, a professor of entomology at the University of Wyoming, USA.
Latchininsky claims that “the outbreaks appeared to be associated with cold and wet, rather than hot and dry, periods and with drought/flood frequencies. He adds, “When the span of analysis was extended to almost two thousand years, the negative association with temperature still held while that with precipitation became inconsistent, and more locusts were found in dry years. The authors concluded that global warming will be beneficial in terms of reducing the locust outbreak frequency, but in view of very inconsistent and even contradictory results of their studies, such prediction appears more a speculation.”
Latchininsky also claims that the same set of Chinese scholars contradicted another Chinese study that found the locust outbreaks benefiting from higher temperatures, and thus would be more recurrent with global warming. Latchininsky claims, “As a side note, recent worldwide molecular studies on L. Migratoria—a widespread migratory locust species that occurs throughout Africa, Asia, Australia and New Zealand), revealed a very complex genetic structure of its populations. In particular, it appears that contrary to traditional views, most of Central and Eastern China is inhabited not by the Oriental migratory locust L. migratoria but by the Asian migratory locust L. m. migratoria. However, to avoid confusion, we followed the conventional point of view on Chinese races of Locusta migratoria.
He argues, as limited data exists today, the recent observations support the notion that certain locust species may benefit from recent climate changes, in particular from increasing temperatures. Latchininsky writes, “The Moroccan locust in Turkmenistan in the past few years consistently breeds at much higher altitudes than 20 or more years ago. According to our observation, this holds true throughout Central Asia (Uzbekistan, Tajikistan, Turkmenistan, Kyrgyzstan), where the vertical limit of permanent breeding areas of this locust shifted up by 300 meters on average. Phenology of the Moroccan locust appears to be more precocious, and development faster than in the 20th century.
The Asian migratory locust responded to the increased thermal resources by starting to produce second annual generation in two separate geographic locations, Uzbekistan and Russia. This phenomenon was considered a rare anomaly in the 20th century and recorded in the literature as a single case in 1927. These (admittedly limited) observations indicate, however, that locusts are likely to expand their ranges and, at least for species of tropical origin, increase the rate of development and possibly the number of annual generations.
For almost two centuries India has had the experience in dealing with locust swarms. India’s Locust Warning Organisation (LWO), which is today leading from the front in the battle against the infestation, was established 81 years ago during British rule.
The country has already experienced major outbreaks in the years 1812, 1821, 1843-’44, 1863, 1869, 1878, 1889-’92, and 1896-’97, which have been documented. India can still use some of these lessons to avert any future crisis that the recent locust outbreaks may trigger. The colonial authorities back then had tried to understand the science behind infestations.
The “War Against Locusts in India” , a research paper published in July 1944 by Hem Singh Pruthi, an Imperial Entomologist and Director at the then Imperial Agricultural Research Institute, New Delhi, records his survey between 1941 and 42 which had reported that locusts left India via Upper Baluchistan due to the excessive cold in Punjab and United Province hills.
The paper mentions that between 1942 and 1943, due to the heavy winter rainfall in Iran and Oman, the locust swarms had moved from Baluchistan to India and passed over Sind and Rajputana and reached as far as Vasna near Baroda (now Vadodara in Gujarat). Due to heavy rainfall, active breeding took place in Rajputana, Sind, Punjab and Bahawalpur areas.
In Mekran ( now in Baluchistan in Pakistan) locusts were joined by other migrant locusts from Persia and destroyed the crops completely. As the soil conditions became very suitable in Baluchistan, the pests laid eggs in various parts of Mekran, Jhalawan, Kharan, Chagai, Lasbela and Chaman. The migrant locusts penetrated Kutch, Bahwalpur, Sind, Rajputana, UP, Bihar and Patna. Due to great efforts taken by the anti-locust organizations, the breeding of the locusts was brought under control in various parts of India, Persia, Iraq and Eastern Arabia.
The answer to that question is a dynamic one. It is an interesting mix of local knowledge and international cooperation. It rests on timely exchange of knowledge and techniques between various states of India as well as with other countries.
It was only after the 1927-’29 locust outbreak in the central and western parts of India that a centralised organisation to gather information about locusts and control was formed. The Standing Locust Committee in 1929 and the Central Locust Bureau in 1930 were two such bodies. This finally led to the establishment of the present-day Locust Warning Organisation.
Destroy breeding grounds During the British rule , one of the key ideas was to destroy the breeding grounds and locust larvae before they could fly. Several techniques were employed for this purpose. One of them was the use of oil-tarred screens to kill locusts (also known as Cyprus screen, because it was popular in that country). They did not prove effective.
The net system The net system involved holding a “capricious” bag and swinging it around fields, trapping young locusts in the process.
The dhotar method This method involved farmers using a blanket to trip locusts resting on bushes.
The ploughing method In this insect-control technique fallow lands will be ploughed where locusts were resting: the escaping insects became an easy target for birds.
These methods required large manpower. The British began employing large number of Indians for this purpose.
The Bombay locust (source wikipedia.com)
Green grasshoppers and brown locusts are close cousins, in fact, both belong to the same grasshopper family. Grasshoppers hop mad and can be abundant and pesky, locusts can fly. What is significant is that locusts have the unusual ability to be total loners or to enter what scientists euphemistically call "a gregarious state" — this is the flying and swarming stage.
Locusts look like ordinary grasshoppers. You may notice they both have long hind legs that help them hop or jump. Sometimes they share the solitary lifestyle of a grasshopper, too. However, locust behavior can be something else entirely. It is when these insects form enormous swarms and spread across regions, devouring agriculture, that they turn into a plague.
During dry seasons, solitary locusts are forced to be together with thin patchy green cover. This sudden gathering releases serotonin (In humans this chemical is sometimes called the happy chemical) in the locust’s central nervous systems, which makes locusts more sociable and promotes rapid movements and more varied appetite.
As a general rule, locust aggregation and eventual phase transformation are favored by habitat discontinuity or patchiness, which can result from a variety of meteorological events. Locusts significantly differ in their life cycles, habitat preferences, and other ecological requirements.
When rains return, leading to moist soil and abundant greens—the environmental conditions are perfect for the bugs: Locusts then begin to reproduce rapidly and become more crowded. Now they turn into what’s called the gregarious phase.
Locusts can even change color and body shape when they move into this gregarious phase. Their endurance increases and even their brains get larger.
Locusts can become gregarious at any point in their lifecycle. On hatching, a locust emerges wingless as a nonflying nymph, which can be either solitary or gregarious. A nymph can also change between behavior phases before becoming a flying adult after 24 to 95 days.
Locust food cooked at home in Kuwait city (Please click the pic above for source)
Locusts have high feed conversion efficiencies. The insects convert low-value carbohydrates like twigs and vegetation into body mass and high-quality food or feed. They contain Omega-3, iron, zinc, Vitamin C, folic acid, B12 and chitin, without cholesterol or saturated fat, antibiotics and hormones.
Protein in locust meals exceed fish meal and reduces costs substantially. Eating insects are considered tasty and nutritious in countries including Thailand, Mexico and Uganda but Americans are less enthusiastic about eating bugs.
According to an interview given to Science Daily , Florence Dunkel, Ph.D., Associate Professor of Entomology at Montana State University and editor of Food Insects Newsletter, "Eighty-five insect species in the U.S. are documented as potential food sources; worldwide, there are 1,900 species."
Dunkel cites locusts, grasshoppers, crickets, silk moth pupae, and beetle and moth larvae among the top insects consumed as food, worldwide.