The UN Food and Agriculture Organisation warned Monday that a devastating new plague of locusts may be about to descend on a large part of Africa, and it appealed for international aid to head off the danger.
The FAO said the first swarms of desert locusts have moved from their spring breeding areas in north-west Africa to Mauritania, Senegal and Mali.
"Many more swarms are expected in these countries as well as in Niger and Chad in the coming weeks," the agency said.
The last Locust plague, a phenomenon that occurs when many swarms combine together, lasted from 1987 to 1989 and caused what then amounted to some 300 million dollars in damages.
A ton of the insatiable insects can devour enough food to feed 2,500 people, and the FAO warned that a dramatic increase in locusts "could threaten crop production in coming months" in a vast area ranging from the Atlantic to western Sudan, where hundreds of thousands of people already are going hungry because of the Darfur conflict.
FAO said additional international aid is urgently needed to monitor and control the infestation, which it added would have to be carried out with conventional pesticides, pending the results of field trials of biological pesticides that are potentially less damaging to the environment.