Signs of hope in East Africa, as control campaign tames locust upsurge

But FAO calls for increased surveillance to lock in gains, prevent a resurgence

 In this Q&A interview, FAO Senior Desert Locust Forecaster Keith Cressman and Cyril Ferrand, Manager of FAO's Desert Locust response in East Africa, discuss progress made in containing the threat posed by the voracious pest in East Africa.

What is the locust situation in East Africa right now?

Cressman: At the moment, swarms are declining rapidly across the Horn of Africa thanks to the large-scale control operations mounted by governments and supported by FAO over the past 14 months and poor rains.  

Swarms in Ethiopia, Kenya and Somalia remain immature and continue to become smaller. Without rainfall, they will not mature and breed. The upcoming rainy season that is expected to be drier than normal should contribute to a further decline in locusts.

So, there is cautious optimism that the upsurge is winding down in the Horn of Africa, especially if poor rainfall limits breeding this spring, and then equally poor rains occur during the summer in northeast Ethiopia and Somalia.

Ferrand: I would add that, compared to the mega swarms of 2020, the swarms now being treated by government teams run from a few hectares to 30 hectares and contain far fewer insects. Remember last year there was one swarm in northern Kenya that was around 2 000 square kilometres in size. Now, daily missions in Kenya are down to one or two a day at the very most, compared to 20 at the peak of the upsurge last year.

Are you saying the locust crisis is over?

Cressman: Absolutely not! Given the right conditions, Desert Locusts are a biological time bomb. They are also professional survivalists and know how to manage weather conditions in a changing climate. We have been surprised twice during this upsurge by atypical weather that dumped unusually heavy amounts of precipitation out of season and sparked an explosion of reproduction.

It would be a fatal error to scale down the response now. On the contrary, surveillance missions should be ramped up, to lock in gains and detect any upticks in locust activity, if the weather does have any more tricks up its sleeve. The maximum number of ground teams must be out actively searching for locust infestations. All control teams must remain ready to react. If current trends continue, operations might be able to come off "high alert status" perhaps after the summer.

Ferrand: Exactly. So much has been gained. But we see that the governments of the region are determined to safeguard these achievements now that the people of East Africa are starting to see the light at the end of the tunnel. Now, countries have systems in place, teams in place, and are maintaining a state of full readiness.

What happens if surprise weather does provoke another round of breeding?

Ferrand: The countries in the region are ready. In one year they went from having very little expertise or capacity to deal with desert locust invasions to a state of very high preparedness. So an enduring legacy of this joint campaign is a very enhanced national locust response preparedness capacity that will benefit East Africa in the future.

How are environmental and safety concerns associated with anti-locust pesticides addressed?

Ferrand: First of all, of course FAO and the affected countries understand concerns over the environment and safety. This has been a top priority from before the operations even began.

Before an air control operation is conducted, the environment is mapped, including settlements, water bodies, wildlife and conservancies for example. Wind direction and speed are assessed and factored in. If swarms are too close to water bodies or the wind direction risk to drift pesticides to water bodies, the operation is cancelled. Spraying has taken place largely on arid land, avoiding potential leaching to water systems. On many occasions operations have to be aborted because the proper conditions are not met.

Cressman: Managing Desert Locusts in order to prevent plagues is one of FAO's original mandates since our founding in 1947, so we have deep experience in this challenging issue.

Over the years, FAO and a range of partners working on Desert Locust management have developed standard operating protocols to guide the planning and execution of control campaigns. Best practices call for exact targeting, precision spraying, and close monitoring so that control operations apply pesticides in a responsible, effective and safe way. Control teams use ultra-low volume formulations very tightly targeted and follow a range of protocols and standard best practices. These are the recommendations we have been driving home from day one.

Are there alternatives?

Cressman: It is widely accepted that the only effective strategy for responding to a Desert Locust upsurge of this magnitude is one that utilizes approved-for-use pesticides. There is just no other way to do it, and the consequences of inaction in terms of the destruction to food crops and pastures in a region already beset by high levels of food insecurity are just unacceptable.

Yes, chemical pesticides used in control can pose risks to human and animal health. Risks can be managed by taking the necessary precautionary measures and strictly following the correct application methods.

Biological alternatives do exist, but they may not be available in suitable quantities and fast enough  when swarms are so vast. By the way, FAO and our government partners did use biopesticides in this current upsurge, when circumstances made use of this slower-acting solution viable.

Moving forward, extensive research is underway on biological control and other means of non-chemical control of locusts. The current focus is on pathogens and insect growth regulators. Thus far, control by natural predators and parasites is limited, as locusts easily outnumber their enemies during upsurges and swarms easily migrate away, leaving them behind.

Ferrand: I would just add that we have worked closely with the government teams to provide training in best practices. Something like 4 000 training manuals and leaflets were distributed across the region after users and actors were exposed to standard operating procedures. Environmental impact assessments have been ongoing. A partnership involving FAO, other UN agencies and regional NGOs has developed community information material in various local languages on safety and best practices. Things like posters, radio announcements, booklets, animations and text messages have been widely disseminated.

Again, we completely understand the concern. All concerns or reports from communities have been carefully investigated and we are pleased to report that we did not face environmental or health incidents in the region. But I would also point to what these operations have achieved in terms of preventing human suffering.  

Locust control operations prevented the loss of 4 million tonnes of cereal and 790 million litres of milk production, protecting the food security of 34.2 million people and avoiding $1.54 billion in cereal and milk losses.

Photo: ©FAO/Sven Torfinn
A Desert Locust eating foliage in Samburu County in northeastern Kenya.