Juvenile locusts, known as hoppers, as well as adults are forming groups after breeding, the Rome-based FAO wrote on its Locust Watch website yesterday.
Ground teams have sprayed more than 13,000 hectares (32,124 acres) in Mauritania and 2,200 hectares in Sudan this month, as well as about 8,000 hectares in Yemen in the first 10 days of November, according to the FAO.
“Intensive survey and control operations should be maintained,” the FAO wrote.
In Yemen, a second generation of locusts started laying eggs about 10 days ago, and hatching and grouping are expected to start from the end of November, the FAO said.
A swarm of locusts covering a square kilometer (0.4 square mile) can eat between 80 and 160 metric tons of crops a day, based on calculations using FAO data.
An adult desert locust can eat its own weight of about 2 grams (0.07 ounce) daily, and swarms can cover several hundred square kilometers, with 40 million to 80 million of the insects per square kilometer, according to the FAO.
Desert-locust distribution can extend over 60 countries during plague years, covering about 29 million square kilometers, according to the UN agency.
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