Year after locust attack, experts monitor movement


Latest field analysis shows swarms persist in Kenya and Ethiopia but other areas in Asia, including Afghanistan and Pakistan, are calm
A year after swarms of locusts invaded parts of Punjab and Haryana besides Rajasthan and Delhi, causing widespread damage to crops, the central government authorities have begun monitoring the pest’s breeding hotbeds in the sub-Saharan desert region and Asian countries.
Experts say nearly half a billion population of the desert locust had invaded India from Pakistan from October 2019 onwards.
Climatic conditions to determine threat of invasion
KL Gurjar, the deputy director of the Locust Warning Organisation (LWO), a subsidiary of the central ministry, is analysing movement of swarms of locusts in coordination with the Food and Agriculture Organisation. He says the climatic conditions in the African and Arabian peninsulas will determine the threat of locust invasion this year.
“We are keeping our fingers crossed though the country is fully prepared for another locust invasion. According to the latest field analysis on February 9, swarms persist in East African regions of Kenya and Ethiopia but other areas, including Afghanistan and Pakistan, are calm. The breeding situation of the insect in the Arabian peninsula in the coming months will help in issuing a warning for this summer,” said Gurjar, the national coordinator on mitigating locust attacks.
It was after about three decades that India experienced a massive locust attack in 2019-20 when the insect moved from Rajasthan to various states, including Haryana, Delhi, Uttar Pradesh, Chhattisgarh and parts of Punjab.
Surge in greenery in Rajasthan attracts locusts
Experts say locusts move with the wind and follow a definite cycle from the Sahara desert in North Africa, into East Africa – Ethiopia, Kenya, Eritrea and parts of Chad. They then move to the Arabian Peninsula and Iran. When they finish the food there, they move to Pakistan and India.
A former vice-chancellor of Himachal Pradesh-based Dr YS Parmar University of Horticulture and Forestry, Hari Chand Sharma, attributes exceptional rains in the last season and upgraded irrigation in the desert state of Rajasthan for the unusual locust invasion.
“Swarms of desert locust normally enter India during monsoon that provides it with a suitable breeding environment. With an increase in irrigation infrastructure, several parts of Rajasthan have seen a surge in greenery, attracting locusts for food while providing a breeding ground as well,” said Sharma, an entomologist.
“Locusts have a pheromone communication that informs them of wind patterns as it determines rainfall, which means more vegetation. From October 15, 2019, to March 15, 2020, there was about 40% excess rain in locust breeding countries in Africa and Asia, which provided plenty of food for the insect,” he said.
With the onset of winter, the locust population leaves the Indian region in October.
No locust colony left in country since August 27
The LWO authorities say no locust colony was left in the country last year.
“After the movement in various parts of the country, locust swarms had returned to Rajasthan to lay eggs in August last year. The insect tends to lay eggs during humid weather. The desert locusts normally live and breed in semi-arid regions and numerous egg colonies were reported in various parts of Rajasthan. But our teams contained the situation and entire egg colonies were wiped out by August 27,” Gurjar added.