This is Steve Ember with the VOA Special English Agriculture Report.
An invasion of locusts from Northwest Africa continues to affect several countries. The United Nations said the number of insects invading crop areas in Mali, Mauritania and Senegal increased in the past two weeks. Locusts have also entered Niger. And the U.N. Food and Agriculture Organization warned last week that locusts could reach Burkina Faso as well.
But the F.A.O. said there were signs of improvement in other areas. Intensive operations to control the locusts began in Northwest Africa in February.
The huge movement of locusts started in Algeria and Morocco. Young locusts began to leave their native territory to search for new places to mate and lay eggs. This migration can cover hundreds or even thousands of kilometers.
Winds can help the flying insects travel long distances. In July, some desert locusts from North Africa arrived on the Cape Verde Islands. The islands are five hundred kilometers from the coast of Africa.
During migrations, locusts eat huge amounts of food. The Food and Agriculture Organization says locusts eat their own weight in food every day. One locust weighs only about two grams. But one ton of locusts can eat about as much food as two thousand five hundred people.
Several countries have asked for aid to control the locusts. So far, there have been international promises of nine million dollars in emergency assistance. Officials from nine countries organized a meeting last week in Algiers to discuss ways to deal with the crisis.
Algeria and Morocco have used chemical poisons. The two countries have treated more than one million five hundred thousand hectares. But good weather conditions have helped the spread of locusts to the south.
Chemicals can be used to kill existing groups of insects. But most of these insecticides are very poisonous and should be kept away from places were farm animals may feed.
By the middle of July, there was a decrease reported in the number of hectares treated in Morocco and Libya. The F.A.O. said this suggests that the situation should become calm in the area in the next few weeks.
Experts say it is important to treat a locust outbreak quickly. After an outbreak, farmers can turn the soil in their fields in late autumn. This can help to destroy some locust eggs.
This VOA Special English Agriculture Report was written by Mario Ritter. This is Steve Ember.