A real Desert Locust epidemic is destroying East Africa for the second year in a row. The flying insect reproduces exponentially and tens of millions of locusts devour fields that are grown for food.
You could hear the rain falling. It is, in fact, a cloud of locusts that fell on a cultural field and devoured everything in its path. A desert-jumped swarm amounts to several million and last year, during the crisis in East Africa, a swarm as large as Luxembourg was seen.
The first signs of this air and cyclical terror in the region go back to 2018, after the passage of two cyclones, which caused an increase in humidity in the Arabian Peninsula, favorable for the development of Schistocerca gregaria, also called “tiger grasshopper” … If any months, the locusts will reach East Africa as far as Kenya. When they are born, the larvae are wingless and are happy to develop on the ground. In the desert, grasshoppers are alone. But the catastrophe is announced when they adopt a herd behavior and form nomadic swarms of millions of individuals who can move tens of kilometers in one day to find their food.
Ravenous grasshoppers when they are in the billions
“They are voracious! They eat about the same amount of their weight every day, describes Cyril Piou, a researcher at CIRAD, the Center for International Cooperation in Agricultural Research for Development, involved in Montpellier in the fight against desert ravens on agriculture. Two grams is not much when there are ten of them, but when there are billions of them, millions of tons can be consumed. ”
A single swarm of 1 square kilometer can swallow the equivalent of consuming 50,000 people in one day. A behavior “catastrophic” for agriculture, “when they arrive in fields where the plants are just beginning their growth. The vegetation is then completely leveled and the crop will be lost this season,” continues Cyril Piou. Since 2020, food crisis warnings have multiplied from Africa horn to Kenya.
No predator can overcome it
For the desert, one of the great migrants of the animal kingdom, unity is strength and protects predators that can not regulate an exponentially growing population when conditions are right. “No predator can go as fast as him,” says Cyril Piou. The grasshopper’s population dynamics are explosive. ” Each generation multiplies the workforce by 3 or 4 and up to 20 times in a very good situation. “Knowing that a female lays a hundred eggs, she generates (in theory; not all larvae survive) offspring of 400 individuals. An exponential Desert Locust outbreak – does it not ring a bell? We are now in the eighth generation since the invasion of Africa. And Desert Locust is always one step ahead.
On 6 February 2021, the UN Secretary-General launched another call for international mobilization. “I urge the international community to respond quickly and generously to ensure an effective response and control of the invasion as long as we still have the opportunity,” said António Guterres of the African Union Platform in Addis Ababa, Ethiopia, one of three threatened countries. Somalia and Kenya, when locusts approach Uganda and South Sudan.
A chemical cloud against the grasshopper cloud
The UN needs money to finance the fight against the “tiger grasshopper”. A chemical battle in an emergency. Apart from a biopesticide based on a fungus, most agents used are based on the massive use of industrial products. “We give planes or helicopters the coordinates of a swarm that landed in the evening,” says Cyril Piou. In the morning, early enough, before the swarm picks up, we will carry out a broad-spectrum chemical spraying that will kill many species other than desert mares, birds and other cold-blooded animals. It is therefore a huge environmental problem, as the amount of pesticides released is enormous. ”
It’s a long struggle. “It’s not a dynamic that can be broken in a few days,” says the desert jumping specialist. The fight against grasshoppers depends on the responsiveness of a network of observers developing in East Africa. A mobile application has been created to report the swarms’ progress in real time. West African countries already have a network in place, with the support of CIRAD, following the recent food crisis caused by the invasion of desert hops between 2003 and 2005. There has not been one since. Because it is better to prevent than to meet a wall.
“What is the smallest flower in the world?”
It is so small that it is difficult to see it … And the plant that produces it itself does not measure more than 2 millimeters. Wolffia is the name of this genus, also called duck. On the water surface, rootless, small but strong. She is also the fastest growing in the world and gives birth to a new plant every 36 hours. An invasive, edible plant that contains almost as much protein as soybeans. According to researchers, famine can be beaten with a dish of duck.
