Armed with insecticide and an awareness campaign, date-exporting Tunisia is battling a bug that devours and kills palm trees and whose spread threatens an environmental and economic disaster.
Originally from Asia, the red palm weevil was first spotted three years ago in the north of Tunis after infested ornamental palms were imported into the country, according to experts.
The beetle, whose adult is barely a few centimetres (around an inch) long and whose larvae feeds off palm trunks, has already infested hundreds of around 30,000 palms in the area.
In a country that exports 100,000 tonnes of dates worth $215 million each year, authorities fear the pest could spread south towards its 40,000 hectares (almost 100,000 acres) of date palm plantations.
Dates are a valuable agricultural export in Tunisia—second only to olive oil—and last year helped to shore up the country's struggling economy after deadly attacks hit its key tourism sector.
From the centre of Tunis to the affluent northeastern suburb of La Marsa, you only need to look up to see rows of infested palm trunks, decapitated where once green fronds have decayed.
Palms infested by weevils perish irreversibly. Once fronds at the top of the trunk turn brown and start to droop, it's usually too late.
"It's a real plague that attacks more than 20 varieties in total," said Mohamed Habib Dhouibi, the scientist selected to lead Tunisia's battle against the insect.
"Before we chop down the date palm trees, we have to treat them for 24 to 48 hours to prevent the spread of the weevil," he said, watching a tree being injected with insecticide in the capital's northern suburb of Ariana.
Female weevils use their snouts to chew a hole in palm tissue and lay their eggs there, according to the US-based Centre for Invasive Species Research.
Male weevils, meanwhile, release pheromones to attract other weevils to palms that are suitable for their larvae to eat.
But these pheromones can also be used against them. When combined with fermented palm material and insecticide, they make enticing traps to catch and kill the pest.
"We've bought 10,000 pheromone traps to set them up all around" Greater Tunis, Dhouibi said.
"I think with those, we'll be able to eradicate the weevil. But it will require time—three, four, five years—and perseverance."
The plan, approved in September by the government, also includes awareness-raising sessions on what an infested palm looks like and a hotline for residents to call in and report suspicious trunks.
A total of 4.2 million dinars ($2 million) have been set aside for the debugging operation, said Agriculture Minister Saad Seddik, visiting the site in Ariana.
Environmental activist Boubaker Houman—who heads the Association of the Friends of Belvedere, the capital's main park—said he was delighted the weevils were finally being tackled.
But he said he regretted all the damage to the capital's palms so far and feared that part of the city's "green heritage" would inevitably be lost.
"If you walk around the park, you'll see palm trees that are more than 100 years old and 20 to 30 metres (65 to 100 feet) high," he said.
"Like olive trees, they're an integral part of the Mediterranean landscape."
Date growers 'scared'
Dhouibi said it was a shame it took three years before authorities adopted drastic measures towards exterminating the weevils.
"Our wealth lies in date palms," he said.
Anis Hassen, head of Tunisia's date producers' association in Tozeur, around 450 kilometres (280 miles) southwest of Tunis, said he and his fellow growers were worried.
"Everyone who works here is talking about the weevils," said the man in his forties, as he showed AFP around his plantation under a cloudy sky.
"Definitely, we're scared. That's why our eyes are like this, always wide open" on the lookout for infested palms, he said.
The date sector provides "jobs for tens of thousands of people. You can just imagine how many families that is," he said.
"We hope the authorities will be able to fight back before it's too late."
US entomologist Mark Hoddle, who heads the Centre for Invasive Species Research, visited Tunisia in October to tell of how red palm weevils were eradicated in South Carolina.
According to the US embassy, "12 percent of Tunisians depend on date farming".
The agriculture minister said authorities aimed to bring the situation under control by springtime so the pests would not reach date-producing areas.
"Our follow-up and monitoring strategy will allow us to stop this plague right here," Seddik said, pointing out that the producing areas were 500 kilometres away.
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