We know therefore that locust swarms have occurred in North Africa for thousands of years. And the horror of this plague, when whole countries are stripped bare by a suffocating mass of insects, lives on to the present day.
In recent weeks, new locust swarms have infested an estimated 6 million hectares of agricultural and grazing land in several African Sahel states, and are spreading fast.
Some 80 million locusts per square kilometer are moving eastward. The summer rainy season -- which aids the locusts' breeding habits -- mean the cloud can grow many times larger. Experts say that in times of outbreak, each generation of locusts is 20 times bigger than the last.
The official in charge of the Locust Group of the UN Food and Agriculture Organization (FAO), Clive Elliot, spoke to RFE/RL from Rome.
"What is happening is that there are many swarms, which have arrived in the Sahelian region stretching from Mauritania, though Mali, Niger -- and just in the last couple of days, also one swarm has reached Chad," Elliot said. "So there are many swarms in those areas, and they are the ones which escaped control operations in northwest Africa during the spring."
Elliot said this massive cloud of locusts is not yet officially classified as a "plague." For that term to be applied, the swarms have to be present in two regions. For the moment, they are only in the western region of the Sahel. But that could change rapidly.
"We are expecting swarms to arrive very soon in Sudan. And once they are into Sudan, they are certainly capable of spreading across the Red Sea to the Arabian Peninsula, and then later on into southwest Asia," Elliot said. "It takes time, and of course it depends how successful control operations are in breaking the cycle of movement."
At risk are Iran, possibly Iraq, border regions of Pakistan, India, and southern Afghanistan.
Controlling locusts involves pesticide sprays. The FAO says it uses mainly organophosphates as sprays, and moves people and livestock away from areas about to be sprayed, in order to minimize exposure.
But, as Elliot admitted, chemical sprays can have a broader negative impact on the environment over a vast area.
"It depends on the pesticide, but yes, there are some limited effects on other animals," Elliot said. "And as they [the pesticides] kill locusts, of course they do affect beneficial insects as well. We are very conscious of this fact, and every effort is made to minimize these side effects."
In Mauritania, the first and westernmost country hit by the locusts, an estimated 1 million hectares of land has been ravaged.
Thami ben Halima is the executive secretary of the UN committee for the eradication of locusts in Mauritania and the rest of the Maghreb. Speaking from Algiers, he told RFE/RL that the situation is "extremely grave."
"The situation is bad in Mauritania, worse than last year," Halima said. "Effectively the population of pests is much greater than last year, and much more widely dispersed, and the ecological conditions for them are good."
Ben Halima said Mauritania has urgent need of more equipment -- including aircraft, spraying experts, and chemicals:
"Effectively we need much more aerial capability. That means planes and helicopters -- planes for spraying, and helicopters both for spraying and observation," Halima said. "We also need better ground capacities, and we also need much more pesticide, and protective [clothing] materials."
Mauritania, one of the poorer countries of a poor continent, has launched an international appeal for help, but so far only Algeria, Morocco, France, and Libya have responded.
The locust swarms coincide with the start of the sowing season, which means the local supply of staple foods will be put at risk if the planting cannot go ahead.
The main loss so far, according to Halima, is the natural vegetation that is essential to maintain the ecological balance in the fragile Sahara desert fringe.
"We have already lost an enormous amount of our natural vegetation, that is to say pasture, as well as treed areas, which are now vulnerable to attack from the desert. You know that trees are absolutely indispensable for [ecological] equilibrium," Halima said.