Why desert grasshoppers can not kill?

After devastating crops in East Africa and the Middle East, grasshopper clouds continued to move to many areas, even though they forced many aircraft to change direction.

Satellite surveillance equipment said desert grasshoppers were still damaging the Asian continent when landing in Yemen, Iran, Pakistan and India threatened food security for tens of millions of people. However, Iranian officials have reported using high-dose pesticides to eradicate and create a dead grasshopper up to 15 cm high in many farming areas.

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Weather and climate change makes grasshopper problem proliferate. (Photo: AFP / getty).

Mehari Tesfayohannes, head of forecast information at the East Africa Desert Grasshopper Control Organization, said : 'Although I have been through a lot of dealing with the grasshopper pest, this year, they are actually reproducing. more abnormal. It is likely that the recent abnormal weather and climate conditions are the perfect conditions for the outbreak of this fierce insect.

In particular, they have invaded at the most difficult time for many poor countries, conflicts and the Covid-19 pandemic. Therefore, a humanitarian crisis in the foreseeable future can occur at any time. '

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Heat map depicting grasshoppers in desert in Africa, the Middle East and South Asia in May 2020. (Graphic: FAO)

Why do locusts thrive? Studies show that some species of grasshoppers can completely change to adapt to different natural conditions . Of the 7,000 species, about 20 are true species recorded on every continent except Antarctica.

The species that has recently appeared in swarms in Africa and Asia is the desert grasshopper (Schistocerca gregaria) , which was formerly a solitary species but when faced with ideal environmental conditions, it exploded.

The evidence is that in-depth studies over a long period of time show that the species has suddenly changed its old habits and started to move, acting in the direction of the herd rather than the individual individuals as before.

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Desert grasshoppers can change their shape and color according to weather and climate. (Photo: JEB).

FAO's prediction, in countries in East Africa, which include part of Somalia, Kenya and Ethiopia, currently the new desert grasshoppers are preparing to bloom until the end of June. If conditions remain favorable and Ineffective control activities will create another 'wave' that can devastate the area from September to December this year and may also arise more frequently in the coming years.

They not only change their properties but also change their color and size, when they change from green or spotted brown to bright yellow.

Their outer form is also smaller, while the brain is larger during evolution. Behavioral changes can occur within hours, while physical changes take longer.

At this new stage, desert grasshoppers formed a herd of about 150 million individuals per square kilometer and had devastating power, equivalent to a food intake of 35,000 people per day.

This has been calculated by FAO on a large scale when desert grasshoppers are damaging on a scale of 2,400 square kilometers in many places, since the beginning of the year.

This air-borne pest can travel more than 161 km a day in the direction of the wind and will lead to immediate consequences there by the vegetation itself on its way.

The scale, speed and devastation of desert grasshoppers has made them a threat to world agriculture.

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In poor African countries, apart from spraying pesticides, there are few options to limit the spread of desert grasshoppers. (Photo: AFP / getty).

Hojun Song, an entomologist at Texas A&M University, said of the species: 'They don't abstain from any geopolitics when they easily penetrate each territory across the border'.

The outbreak of desert grasshoppers epidemic, according to experts from the International Institute on Climate and Social Affairs (Columbia University) Muhammad Azhar Ehsan, is due to heavy rainfall and the Amphan storm that triggered further reproduction. This is due in part to unusual changes within decades of the thermal slope in the Indian Ocean bipolar region in 2019.

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The Covid-19 pandemic is making it extremely difficult to prevent desert grasshoppers and the risk of double disasters. (Photo: Xinhua).

Keith Cressman, FAO's grasshopper prediction expert, said the key is to detect the species as soon as they have not developed the wings to be easier to control.

The study found that during the first month of maturity, plants devastated and laid eggs and exponentially hatched, 20 times per generation. This is a very difficult cycle to break, so remote monitoring and interception is an important part of the grasshopper control strategy.

"If there is no solution, the problem is like a big fire in a place where there is no fire ," Mr. Cressman said.