(Recasts, adds entomologist from paragraph 9)
By Alphonso Toweh
MONROVIA, Feb 3 (Reuters) - Liberia’s agriculture minister said on Tuesday that caterpillars infesting villages, destroying crops and threatening food security of an estimated 350,000 people were of the Achaea catocaloides species.
The species thrives in forest environments and eats all vegetation, including cocoa trees, which could be a threat to plantations in West Africa if the conditions remain conducive for reproduction, the scientist who identified it told Reuters.
The caterpillars were previously thought to be the destructive "army worm" moth caterpillar. They have already spread to Guinea and have been flagged as a threat to farmers in neighbouring Ivory Coast, the world’s top cocoa grower.
"They are primarily forest insects that feed on trees, such as the Dahoma. The insect population can develop in large numbers and then attack agricultural crops," Agriculture Minister Chris Toe told reporters in the capital Monrovia.
Liberia, devastated by over a decade of civil war that ended in 2003, declared a national state of emergency last week after caterpillars were reported to have infested more than 100 villages, including several over the border in Guinea.
Guinea exports agricultural crops to Liberia, supplying much of the staples eaten in Liberia’s capital Monrovia.
The United Nations Food and Agriculture Organisation said last week the insects, then thought to be army worms which are known to ravage crops, threatened to spread across West Africa.
The insects have caused panic in some villages, contaminating water supplies with their faeces, the FAO said.
"I think this is a seasonal threat. From our experience in Benin, the moth will disappear by early or mid-March," Dr. Georg Goergen, an entomologist at the Benin-based International Institute for Tropical Agriculture, told Reuters on Tuesday.
"They do eat everything ... they do attack cocoa. The threat to Ivory Coast depends on how long the caterpillars are able to maintain their population levels," he added.
Much of Ivory Coast’s cocoa is produced in the west of the country, which has already had a troubled 2008/09 season with output hit by poor weather, disease and political infighting.
None of the caterpillers have been reported in Ivory Coast but a team of experts has been dispatched to the border area to monitor plantations and draw up emergency plans.
Goergen said that the cooler weather at the beginning of the year and deforestation, which deprived the caterpillars of their food in the forests, had caused a population boom and probably sent the pests hunting for food across Liberia.
"If the conditions are right, they could produce one or two generations ... Like with locusts, the best thing is monitoring and early warning. But for emergency solutions, there is nothing but to spray." he warned. (Additional reporting and writing by David Lewis in Dakar; Editing by Alistair Thomson)