By Tom Miles
GENEVA, Sept 3 (Reuters) - Yemen can expect substantial swarms of locusts in coming months as its war hinders pest control measures needed to prevent devastating plagues, the United Nations said on Tuesday.
If allowed to breed unchecked in favourable conditions, locusts can form huge swarms that can strip trees and crops over vast areas, posing a particular danger in Yemen where millions already risk starvation.
The U.N. Food and Agriculture Organization (FAO) said the regional situation was worrying: most serious in Yemen, Pakistan and India, and at risk of worsening in Ethiopia and Eritrea.
"Yemen is a key frontline country for Desert Locust because of its winter breeding areas along the Red Sea and Gulf of Aden coasts, the source of devastating plagues in the past," FAO locust expert Keith Cressman told Reuters.
Vital equipment such as four-wheel drive vehicles had been looted or lost in Yemen's four-year war, making it virtually impossible to monitor or control the locusts, he said.
Swarms were likely to keep breeding in Yemen's interior for one or two months, but winter rains could foster three generations of breeding until around March, each multiplying the population 20-fold.
"Given that current locust numbers are already much higher than normal in the region, there is a high probability that such outbreaks will develop this year and affected countries should prepare themselves and take the necessary action," Cressman said.
Adult locust swarms can fly up to 150 km (93 miles) a day with the wind and adult insects can consume roughly their own weight in fresh food per day. A very small swarm eats as much in one day as about 35,000 people: a devastating threat to crops.
The last major upsurge was in 2003-2005 when more than 12 million hectares were treated in west and northwest Africa, incurring a cost of about $750 million including food aid. The current outbreak began last year and some 1.2 million hectares have been treated, mainly by Iran, Saudi Arabia, Sudan, and Eritrea over winter and spring, and by India and Pakistan this summer, Cressman said.
Those control operations have prevented a spread of locusts on a much larger scale, and the situation is not yet a major upsurge, with a warning level of "yellow/threat" rather than "red/danger" on the FAO scale, Cressman said.
"Red, the highest warning level, is reserved for the absolutely worse case situation, which we have not reached yet and hope not to." (Reporting by Tom Miles; Editing by Andrew Cawthorne)
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