Locust swarms can vary from less than one square kilometre to several hundred square kilometres. There can be at least 40 million and sometimes as many as 80 million locust adults in each square kilometre of swarm.
Here’s everything you need to know about the latest threat to India from the skies.
What is a Desert Locust?
The Desert Locust is one of about a dozen species of short-horned grasshoppers (Acridoidea) that are known to change their behaviour and form swarms of adults or bands of hoppers (wingless nymphs). The swarms that form can be dense and highly mobile. The scientific name for Desert Locust is Schistocerca gregaria (Forskal).
How many species of locusts are there in world and India?
There are 10 important species of locusts in the world: Desert Locust, Bombay Locust, Migratory Locust, Italian Locust, Moroccan Locust, Red Locust, Brown Locust, South American Locust, Australian Locust, and the Tree Locust.
Only four types of locust, viz, Desert locust (Schistocerca gregaria), Migratory locust (Locusta migratoria), Bombay Locust (Nomadacris succincta) and Tree locust (Anacridium sp) are reported in India.
The Desert Locust is most important pest in India as well as in intercontinental context.
What is the history of locust invasion in India?
Historically, the Desert Locust has always been a major threat to man’s well-being. The Desert Locust is mentioned as curse to mankind in ancient writings, viz, Old Testament-Bible and the Quran.
The magnitude of the damage and loss caused by the locusts is very gigantic beyond imagination as they have caused the starvation due to its being polyphagous feeder, and on an average small locust swarm eats as much food in one day as about 10 elephants, 25 camels or 2500 people.
Locust do cause damage by devouring the leaves, flowers, fruits, seeds, bark and growing points and also by breaking down trees because of their weight when they settle down in masses.
What countries are affected by the Desert Locust?
The invasion area of desert locust covers about 30 million sq km which includes whole or parts of nearly 64 countries.
This includes countries like North West and East African countries, Arabian Peninsula, the Southern Republic of erstwhile USSR, Iran, Afghanistan, the Indian subcontinent.
During recession periods when locust occurs in low densities, it inhabits a broad belt of arid and semi-arid land which stretches from the Atlantic Ocean to North West India. Thus, it covers over 16 millions sq km in 30 countries.
Is there any border meeting conducting between the nations
Yes. There are regular meetings of Indo-Pak Border at active locust season.
What is the difference between locusts and grasshoppers?
Locusts are part of a large group of insects commonly called grasshoppers which have big hind legs for jumping. Locusts belong to the family called Acrididae. Locusts differ from grasshoppers in that they have the ability to change their behaviour and habits and can migrate over large distances.
How many breeding seasons are there for locusts?
In all there are three breeding seasons for locusts (i)Winter breeding [November to December], (ii) Spring breeding [January to June] and (iii) Summer breeding [July to October]. India has only one locust breeding season and that is Summer breeding. The neighboring country Pakistan has both spring and summer breeding.
How far and how fast can the Desert Locusts migrate?
Desert Locusts usually fly with the wind at a speed of about 16-19 km/h depending on the wind. Swarms can travel about 5-130 km or more in a day.
Locusts can stay in the air for long periods of time. For example, locusts regularly cross the Red Sea, a distance of 300 km. Solitary Desert Locust adults usually fly at night whereas gregarious adults (swarms) fly during the day.
Do swarms fly at night?
Occasionally during periods of unusually warm temperatures, swarms will fly during the early evening but rarely will they continue to fly during the entire night unless they happen to be over water (sea, ocean).
How big are the swarms and how many locusts are there in a swarm?
Locust swarms can vary from less than one square kilometre to several hundred square kilometres. There can be at least 40 million and sometimes as many as 80 million locust adults in each square kilometre of swarm.
How long does a Desert Locust live?
A Desert Locust lives a total of about three to five months although this is extremely variable and depends mostly on weather and ecological conditions.
The life cycle comprises three stages: egg, hopper and adult. Eggs hatch in about two weeks (the range is 10-65 days), hoppers develop in five to six stages over a period of about 30-40 days, and adults mature in about three weeks to nine months but more frequently from two to four months.
Can locusts be detected by satellites?
Weather satellites and other satellites used to monitor the environment cannot detect locust individuals or swarms.
However, the highly sophisticated satellites used by the military can indeed detect locusts but these images are not available. Even if they were, it is unlikely that national and international locust organizations would have the ability to interpret the hundreds of images that would be produced on a daily basis.
How can locusts be controlled?
At present the primary method of controlling Desert Locust swarms and hopper bands is with mainly organophosphate chemicals applied in small concentrated doses (referred to as ultra low volume (ULV) formulation) by vehicle-mounted and aerial sprayers and to a lesser extent by knapsack and hand-held sprayers.
FAQ: Courtesy, Directorate of Plant Protection, Quarantine and Storage, Ministry of Agriculture and Farmers Welfare.
