Locust invasion in Asia and Africa can be linked to climate change, says new Down To Earth investigation

New Delhi, February5, 2020: Even as the coronavirus outbreak rules the headlines, a new crisis has been brewing. In December last year, vast hordes of locusts invaded crop fields in Rajasthan and Gujarat. More recently, Pakistan, facing its worst locust attack in decades, has declared a national emergency to tackle the menace. And massive swarms have ravaged large swathes in eastern Africa. 

While locust invasions in these regions are not unusual phenomena, latest investigations by Down To Earth, the environment and development fortnightly, has connected these recent attacks to climate change. Says Down To Earth editor Sunita Narain: “There is a change in the way locust invasions are happening, and this has to do with unseasonal rainfall not just in India, but in other breeding grounds of this insect.” Down To Earthis published from New Delhi with support from CSE. 

Locusts breed exponentially – in their first breeding period, they increase by 20 times; in the second, by 400 times, and in the third, by 16,000 times. This means if there is an extended period of breeding, the swarms will grow very large. Locusts need wet and green lands to proliferate. Unseasonal rains in Pakistan’s Sindh area and western Rajasthan in India, with the monsoons extended almost till October, meant the insects got ideal conditions locally to breed. 

To add to this, cyclones in 2018 brought extreme rain to the Arabian Peninsula, creating lakes in the desert; there was unseasonal heavy rain on the Red Sea coast as well. All these conditions, points out the Down To Earth report, led to gigantic swarms of the insect descending on neighbouring regions. 

An average locust swarm can contain eight million insects. In one day, these can devour as much food as that eaten by 2,500 humans or 10 elephants. The scale of the devastation they wrought in Rajasthan and Gujarat is not fully estimated, but the governments in these states are reported to have sprayed pesticides over an area that is thrice the size of Delhi. 

In its report, Down To Earth  interviewed Keith Cressman, senior locust forecasting officer with the UN’s Food and Agriculture Organization. Cressman believes that changing wind patterns over South Asia and the increase in the frequency of cyclones in the area have aided in the breeding. 

Africa’s eastern parts have witnessed one of their worst locust attacks last year. Kressman says they are linked to the attack in India and Pakistan. Some of the locusts that bred after the unusually wet season in the Arabian Peninsula and Red Sea, moved towards Yemen and from there to Africa. 

Says Narain: “It is not difficult to understand what we are witnessing in our inter-dependent and globalised world. It is not only about migration of people, or flight of capital, or greenhouse gases that know no boundaries. It is also about globalisation of insect infestations and pest attacks because of the changing weather.” 

Check out Down To Earth’s coverage on the subject:

For Sunita Narain’s edit:

Watch out for a session on climate change at CSE’s forthcoming Anil Agarwal Dialogue 2020 (February 9, 2020). Presentations will be uploaded here:

For more information, contact Sukanya Nair of The CSE Media Resource Centre,, 88168 18864.