"There are signs that the situation is moving towards the early stages of an upsurge. International donor assistance is urgently required to prevent a plague from developing," warns FAO's Locust Group.
In Morocco, intensive aerial and ground control operations, treating up to 20,000 ha per day, are in progress against swarms that are laying eggs in the spring breeding areas in the Draa Valley on the southern side of the Atlas Mountains. It is likely that similar infestations extend into western Algeria, near the Moroccan border.
In the next few weeks, more swarms are expected to arrive in Morocco and Algeria from northern Mauritania and the Western Sahara.
In Mauritania, widespread hatching and band formation continue in the north near the borders of Morocco and the Western Sahara. Adults are forming swarms in parts of the north and northwest where vegetation is drying out, and some of these swarms have been seen moving northwards.
In Niger, adult densities are increasing in the southern Air Mountains where egg-laying and hatching are in progress. Many small swarms were seen moving northwards in early March. They may appear in southern and central Algeria.
Control operations are in progress in the affected countries but national resources are rapidly being drained. During the first half of March, more than 250,000 ha were treated in Morocco, compared to about 2,000 ha in Mauritania where a severe shortage of funds for pesticide and operations continues to limit the ability to reduce the number of swarms that will eventually move towards the spring breeding areas.
Last month, FAO launched an appeal to donors for $6 million urgently needed to support and maintain operations in Mauritania and another $3 million for Mali, Niger and Chad in order to avert a plague. The last plague in 1987-89 lasted several years and costed more than 300 million dollars before it came to an end.
Sudan and Egypt
Across the continent, desert locust populations unexpectedly shifted from the Red Sea coastal plains to the interior of northern Sudan and southern Egypt during the first week of March, according to the latest FAO report.
In Saudi Arabia, locust numbers have reportedly declined along the Red Sea coastal plains as swarms moved across the Red Sea to northeast Africa.
In Sudan, a few small mature swarms appeared near Dongola and were reported to be copulating.
In Egypt, larger swarms were seen near Lake Nasser and locust adults appeared in the oases in the New Valley while, on the Red Sea coast, control operations continued on both sides of the Egyptian-Sudanese border.
FAO reiterated that if survey and control operations have to slow down or be interrupted during this spring in Northwest Africa, more swarms will form and move to the Sahel in West Africa at the beginning of the summer growing season.
"If operations are not effective during the summer, this could not only have a dramatic impact on food security within the Region but the current situation could develop into a plague by the end of the year," FAO warns.