FIGHTING AN INVASION

Why locust control must be done before 10am

Once they get sufficient energy, they move again by 9.30am to 10am.

In Summary
  • The current swarms are mainly immature adults that are pink-red.
  • They land in an area and eat for about one hour or 30 minutes and take off.
Farmers in Kyuso district of Kitui try to scare away a swarm of locusts during the first infestation in February last year.
SHOO! Farmers in Kyuso district of Kitui try to scare away a swarm of locusts during the first infestation in February last year.
Image: MUSEMBI NZUNGU

When a swarm of locusts comes into the country, it is reported formally or informally.

Informal reporting is where every resident can talk about it, but as far as desert control is concerned this is wasted information until that time that information is relayed using the right tools, including elocust 3m.

This information goes to the database where it appears on a map. But the informal reporting can only be helpful after trained scouts visit the area and use elocust 3m to report.

The current swarms are mainly immature adults that are pink-red. They land in an area and eat for about one hour or 30 minutes and take off. The swarms do this the whole day until evening when they have to roost because they don't fly at night.

The surveillance team identifies the area where the swarms have roosted so they can plan for control, usually done in the morning before 10am.

At sunset, the swarms roost in trees and they descend from the trees to the ground when the sun rises in order to warm themselves. Once they have got sufficient energy, they move again by 9.30am to 10am.

So, if you are doing control and reach there after 10am you will find them gone. Controlling them in the evening is tricky because you do not know where they are going.

Locusts do not sleep on the ground because it is normally cold at night. Even hoppers sleep on the shrubs and descend once the sun rises.  

The challenge in surveillance is the movement. If you have swarms flying over a forest like Mt Kenya and a scout is trying to follow them using a motorcycle, sometimes you cannot pass through the forest.

But the scouts on the ground can network and communicate when the swarms cross to the other direction. Or if swarms are flying over Lake Turkana and you don't have a boat to follow them, you communicate with the scouts on the other side to follow the swarms and know where they will land. The challenge with surveillance is the movement in a varying landscape.

Dr Muo Kasina, chairman of the Entomological Society of Kenya