As Yemen's bloody conflict continues into its eighth month and residents recover from two unprecedented cyclones in the span of weeks, the United Nations is now warning the country faces another ticking time bomb — hordes of locusts.
Desert locusts are intermittently present in large numbers in Yemen, where they await sufficiently moist soil to breed. Despite being the Arab world's poorest country, Yemen's agricultural officials have often been able to mitigate the damage inflicted by locusts, which can fly along with the wind nearly 100 miles per day and ravage practically any crop in the country.
A combination of historic rains brought by cyclones Chapala and Megh this month and an unceasing security vacuum mean both the potential for infestations and the lack of government response are particularly acute.
Prior to Chapala making landfall on November 3, the UN's Food and Agricultural Organization (FAO) observed low level breeding activity among locusts in Yemen.
"They don't need much rain in order to survive," said Keith Cressman, the FAO's senior locust forecasting officer. "If they get 25mm or 1 inch in a month it's enough for them to breed."
Chapala, which hit southern Yemen with exceptional intensity on November 3, left close to 200mm of rain in certain areas, enough to possibly keep the soil moist enough for female locust to deposit eggs for six months, said Cressman.
Female desert locusts can lay eggs on three occasions within their lifetime, each time dropping roughly 100 eggs into the soil. The vast majority of offspring die either before hatching or in their wingless "hopper" stage. But the rate of reproduction still can lead to a 20-fold increase for each subsequent generation, said Cressman, meaning Yemen could be beset by locust swarms of biblical proportions by Spring 2016.
"The worst case scenario would be that the national teams wouldn't be able to undertake surveys in these areas, so we have no confirmation of what the locust situation is," said Cressman. "Assuming that the winds associated with the cyclones may have brought some locusts into areas they wouldn't normally be in, they have the possibility to breed unchecked. You could have one or two generations of breeding."
The massive rainfall totals of November could also provide the vegetation that locusts need to hatch and develop — protection that allows them to build up strength before wiping out other plant life.
According the FAO, just a small swarm of locusts is capable of devouring enough food in one day to feed 35,000 people.
Yemen has for years relied on imports to provide the majority of its food supplies, and any further diminishing of an agricultural sector already disrupted by war could spell further misery for its 24 million residents — more than 80 percent of whom require some sort of humanitarian assistance. Prior to Chapala's arrival, the UN already classified 10 of Yemen's 22 governorates as "one step below famine."
The FAO warns that seasonally heavy rains in the nearby horn of Africa could lead to similar problems. Should large scale swarms beset Yemen, they may, after ravaging agricultural areas in the country, piggyback on wind streams to make the crossing to Ethiopia, Djibouti, or Somalia. In 2007, a moderate sized swarm flew as far as Kenya, where they became the country's first infestation in a half century. In extraordinary cases, locusts are capable of crossing entire oceans, and have been documented moving from West Africa to the Americas.
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