Sahel locust threat: millions of dollars can be saved

...if there is good early warning followed by early response to locust threats before they become completely out of hand.

by Keith Cressman

Senior Locust Forecasting Officer,

FAO, Rome

This year the Sahel is facing the most serious Desert Locust threat since the last plague in 2003-05. More than 50 million people could be affected in Chad, Mali, Mauritania and Niger.

The threat originated further north along the Libyan/Algerian border at the beginning of the year. Normally, both countries can easily manage locust infestations in their territories. However, this year was different. The infestations occurred in a border area that was insecure. Although both countries managed to undertake survey and control operations during the spring, they could not stop the formation of hopper bands and adult swarms. When the vegetation in both countries started to dry out in May, the swarms moved south to greener pastures.

Survey teams prepare to depart

from the Locust Base at Agadez, Niger 

with military escort (source: CNLA/Niger)

The incoming locusts scattered over a distance of about 3,000 km in the Sahel from northern Mali to Darfur, Sudan. Luckily most of the locusts remained in the northern part of the Sahel and did not reach cropping or pasture areas, except in Niger. The invasion continued until about mid-June. The national locust centre in Niger mounted control operations against the incoming adults but this could not stop egg-laying. Hatching in early July to August in Mali, Niger and Chad was followed by a second generation of breeding in September. Bearing in mind that locusts increase some 16-fold with every generation, there could be 250 times more locusts in the Sahel by November than at the beginning of the summer.

Early instar hoppers from second generation breeding 

that have formed small but numerous hopper bands in 

northeast Chad near Fada in mid-September 2012 (source: ANLA/Chad)

So far, hopper bands have started to form near Fada in northeast Chad but they are also probably forming in parts of northern Niger and northern Mali. From mid-October onwards, there is an increasing risk that swarms will form and leave the Sahel, migrating north to Libya, Algeria and perhaps reaching Morocco.  Swarms are also expected to migrate to northwest Mauritania and Western Sahara. There is a lower risk of a few swarms getting into cropping areas in Mali and Niger. This could coincide with the seasonal harvest. The scale and exact timing of the migration is difficult to estimate with any precision because not all areas can be accessed and much depends on rainfall and temperature in the coming months, which are difficult to predict. But it is safe to say that any migration this year will be much smaller than during the last plague of 2003-05.

The current insecurity in the Sahel this year, in particular in northern Mali and northern Niger has dramatically affected locust operations in both countries. National teams are unable to conduct survey and control operations in northern Mali although there is one local Tureg team that can survey in parts of the Adrar des Iforas and Tamensa. Military escorts must accompany locust teams in Tamesna, the Air Mountains and the Tenere to ensure their safety in Niger. All of this leads to limited operations and causes great uncertainty regarding the situation in both areas.

What is the role of FAO, and what has the Organization done to address the threat?

A farmer in southwest Mauritania in September 2004 

during the last Desert Locust plague 2003-05 (source: FAO)

Since 1975, FAO has operated a 24/7 Desert Locust early warning system called the Desert Locust Information Service (DLIS) at its headquarters in Rome. The results from national survey and control teams in 25 countries of Africa and Asia are analyzed to assess the current situation, forecast the scale, timing and location of locust breeding and migration up to six weeks in advance, and to provide early warning to affected countries and the international donor community. For example, DLIS warned Sahelian countries in late March that swarms would arrive at the end of May from northwest Africa.

With the assistance of the international community, additional teams 

are mobilized for locust surveys in order to better monitor developments

 in the field and the potential threat to agriculture and livelihoods 

(source: CNLA/Mauritania

Millions of dollars can be saved if there is good early warning followed by early response to locust threats before they become completely out of hand. Despite this preventive control strategy, locust emergencies do occur but less often than in the past. When this does happen, FAO coordinates control campaigns and donor assistance. 

In June of this year, FAO appealed for $10 million to address the Desert Locust threat in the Sahel. So far, more than 40% has been received, which has allowed countries to carry out the necessary survey and control operations, expand the number of ground teams and airlift pesticide, with the help of WFP, from those countries in the region with available stocks to countries in need, so called Pesticide Triangulation, to avoid pesticide stock piling in the region. Technical assistance has been mobilized to strengthen national capacities and abilities to respond to the threat in an effective and timely manner. The objective of all of these efforts is to protect crops and livelihood, safeguard the environment, and contribute to food security in the region.

www.fao.org/ag/locusts

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