Study locusts at micro,macro levels

The article “Farm raiders” (1-15 February, 2020) was interesting and informative. Locust swarm attacks over India, particularly Gujarat and Rajasthan, are not new. As an agrometeorologist with the Indian Council for Agricultural Research, New Delhi, I participated in the surveillance and

monitoring of locusts in 1972-1973. During that period, there was a huge invasion of swarms in Rajasthan, Gujarat and to some extent in Punjab and Haryana. I recall, we formed a good surveillance team in the Indian Agricultural Research Institute consisting of scientists and experts from various disciplines to study day-to-day developments of the attacks and farmers’ feedback. We also collaborated with the state agriculture departments of Rajasthan and Gujarat as well as with the India Meteorological Department to cull out the weather data for better analysis and interpretations. Locust attacks subsided 1974 onwards.

But suddenly we are once again experiencing its wrath! We need to monitor not only air temperature, but also, and more importantly, the soil temperature and the moisture status at shallow depths, say 10-20 cm, where locusts lay eggs and breed. Another significant meteorological factor contributing to the swarms’ migration and journey is the upper air wind speed and trajectory, say the easterly jet streams, over the globe. The convergence and divergence of weather systems and cyclones/depressions in the atmosphere too play a role. It is better to study the abiotic factors at both micro and macro levels.

For better forecasting studies, we need to have an integrated approach involving experts and scientists from various fields like entomology, plant pathology, meteorology, economics and plant physiology. International cooperation with the World Meteorological Organization and the Food and Agriculture Organization can help tackle this global problem.

K K NATHAN NEW DELHI