Residents burned tires and trash in the streets Thursday trying to drive off swarms of locusts descending on the region in what a U.N. agency called the worst sub-Saharan invasion in more than a decade.
The flying swarms reached densities of 50 million locusts per half square mile and began landing on the Mauritanian capital Wednesday.
Flying south from hatching grounds in North Africa, the swarms were landing to eat their weight each day from scarce trees and crops, international experts warned.
"It's beautiful to see and funny, the locusts on parade in the sky," said resident Aicha Bint Sadibouh. "But when they invade the streets and homes, it's disastrous."
Overnight Thursday, inhabitants across the desert city burned what they could spare, hoping the acrid smoke would drive away insects.
Locusts crunched underfoot with each step Thursday in the sandy streets of the capital.
The Rome-based U.N. Food and Agriculture Organization said unseasonable rains last year prompted a larger-than-normal hatch, leading to the heaviest locust infestation since 1988.
While the locusts — which resemble flying grasshoppers — have yet to reach "plague" proportion, experts said, the swarms are still growing.
The FAO and others have appealed for international donations to combat the locusts.
The invasion also has reached Mali, while Burkina Faso, Chad and Darfur, Sudan, are also at risk. The latter two regions already are caught in a humanitarian crisis from what the West calls an ethnic cleansing campaign by government-backed Sudan militias against non-Arab African villagers.
The president of Mauritania's southern neighbor, Senegal, canceled a foreign trip late last month to deal with the locusts in the far eastern part of that country.
Senegal's neighbor, Gambia, declared a state of emergency. France is sending teams of experts to assist.
Locust swarms can travel more than 60 miles each day, the FAO says, and include several billion insects.
By Ahmed Mohamed