Recent cyclones and heavy rains in Yemen and Africa could trigger locust plagues, UN agency warns

As unusually heavy and widespread rains continue in northwest Africa, the Horn of Africa and Yemen, the Food and Agriculture Organization (FAO) warned today that the extreme weather conditions could favour Desert Locust breeding, and stressed the need closely monitor the situation over the next six months to prevent plagues.

“Extreme weather events, including torrential downpours, have the potential to trigger a massive surge in locust numbers. Rain provides moist soil for the insects to lay their eggs, which in turn need to absorb water, while rains also allow vegetation to grow which locusts need for food and shelter,” said Keith Cressman, FAO Senior Locust Forecasting Officer in a news release.

According to FAO experts, the locust situation in countries normally affected by Desert Locust remained mostly calm in October with only small-scale breeding activity detected.

However, the experts warned that impact of El Niño in Africa and the unprecedented back-to-back tropical cyclones Chapala and Megh in the Arabian Peninsula and the Horn of Africa could aid the insects in forming destructive swarms.

“The effects of a locust plague can be devastating on crops and pastures and thus threaten food security and rural livelihoods,” added Mr. Cressman.

The agency experts said that once airborne, swarms of tens of millions of locusts can fly up to 150 kilometres a day with the wind.

Female locusts can lay 300 eggs within their lifetime while a Desert Locust adult can consume about two grams of fresh food every day, which is roughly its own weight and a small swarms eats the same amount of food in one day as about 35,000 people.

FAO operates a Desert Locust Information Service that receives data from locust-affected countries and the information is analysed regularly to assess the current locust situation and provide forecasts up to six weeks in advance and if required, issue warnings and alerts.

The agency also said that the recent tropical cyclones Chapala and Megh that hit Yemen also affected north-eastern Somalia, where torrential rains which far exceeded the annual average rainfall for the entire year caused flooding and damage.

FAO reported that the winter breeding areas along both sides of the Red Sea, seasonal rains began in early October, which is slightly earlier than normal and warned that if the rains continued, there would be sufficient time for two generations of breeding to occur this year in the coastal areas of Sudan, northern Eritrea, southeast Egypt, Saudi Arabia and Yemen.

FAO stressed that prevention is the key in reducing the extent to which Desert Locust can affect agricultural areas, mainly through early warning and early reaction.

The agency said that it is imperative that countries conduct necessary field surveys after unusually heavy rainfall, and maintain them on a regular basis for routine monitoring of breeding conditions and locust infestations.

Further, FAO said that finding of significant infestations requires control operations to avoid a further escalation in locust numbers, and asserted that the results of survey and control operations must be reported quickly and accurately so that swift decisions can be taken to prevent the spread of locusts to other countries.

FAO observed that while such measures helped in curtailing the frequency and duration of plagues since 1960s, climate change activities today are leading to more frequent, unpredictable and extreme weather that poses fresh challenges on how to monitor locust activity.

Lastly, the agency stressed that without regular monitoring, locust outbreaks followed after floods and cyclones could lead to plagues and added that warmer conditions could possibly shorten the incubation and maturation periods of the insects.