Locusts are here – not in Rwanda, not yet anyway. They are in the neighbourhood. Their presence alone should be enough warning. But just in case we haven’t got it, the government has told us to be on our watch.

And so we should. They are an unimaginable pestilence.

Over the last few weeks, desert locusts have ravaged parts of Eastern Africa, and they are not done yet. They have come down from the Arabian sands where they breed, gone through Eritrea, Djibouti, Ethiopia, Somalia, and now into Kenya, devouring all vegetation on the way.

Experts warn of their moving into Uganda, South Sudan, and probably beyond.

Most of these are the same countries that usually suffer from extremities of weather.

Sometimes the sun beats down relentlessly for months or even years. It does not rain. There is a drought. No crops. Famine sets in. People starve.

Reed-thin humans, hardly able to move, can be seen searching in the dry land for roots and other plants that may have withstood the drought for food. No pasture. Animals die. The land is strewn with carcases cleaned up to skeletons by vultures and other scavenging creatures.

Then it rains without let up. The parched earth drinks it all up, but soon it is saturated. Floods occur. Another round of destruction begins.

In between, times can be normal. The seasons are regular. Rain and shine are predictable and harvests are good.

 And now there is this: a plague of locusts. Mercifully, they do not come around too often.

Not many people in Rwanda today know much about this destructive menace. Some have been asking what sort of creatures they are. Are they like armyworms? Are they as destructive as they say or is it simply exaggeration?

A few facts will show how dangerous they can be. According to experts, a typical swarm contains 150 million locusts per square kilometre, and may be twenty kilometres wide and forty kilometres long. They can cover between one and two hundred kilometres a day and eat up to two hundred tonnes of vegetation during the same time.

You can well imagine how long they would take to cover Rwanda and eat up all the vegetation in the country.

We may not know much about locusts today, but they were once the terror of East Africa and the cause of famines that regularly ravaged the region in the first part of the twentieth century. The devastation they caused was so great that locusts became part of the local lore.

The generation that experienced their destruction and the resulting famines is long gone. The one that followed learnt much of it from the lore.

The one of today had no idea, until now and may not fully appreciate it since it is thought to be far away.

But the destruction has always been real and worrying enough for the countries of Eastern Africa to form an organisation to help control the plague of locusts. In 1962 they formed the Desert Control Organisation for Eastern Africa (DLCO-EA) with headquarters in Addis Ababa, Ethiopia.

By and large, the DLCO-EA did a good job. Greater and more effective surveillance, and appropriate and timely control measures significantly reduced the locust menace. Since the 1940s there hasn’t been a locust invasion on a destructive scale as used to happen.

Its success in controlling locusts led the organisation to take on other tasks like the control of tsetse fly and armyworm.

Growing up in East Africa, I remember seeing four-wheel drive vehicles with the DLCO-EA logo emblazoned on their side on regular service in tsetse fly infested areas.  Then they became less frequent. Reading stories of locust invasion today, I have not seen the DLCO-EA mentioned anywhere.

Its absence could be due to any number of reasons.

For instance, it could be that the organisation was so successful that it was no longer needed, or all those people scouring the countryside for signs of pests were no longer needed.

Or there are now better and more effective detection and control methods than having vehicles and feet on the ground. Advanced satellite and early warning technologies have improved surveillance.

It could also be that people simply went to sleep and forgot about keeping an eye on locusts breeding sites, and worse, did not provide for their control once they spread out of those sites.

If it is the last one, and there are indications that may be so in some places, it is a serious indictment on the level of preparedness and management of disasters in the region.

There have indeed been stories of lack of pesticides and aeroplanes or other mechanisms to spray locusts and stop them spreading further and wreaking more havoc.

We have seen pictures of little herdsboys throwing stones in the bush to scare away the locusts to no effect. That may work with boys chasing away birds in the Kanyonyomba marshland rice fields, but not with a huge swarm of locusts.

There is no excuse to be caught unprepared.

Locusts do not fall from heaven suddenly. They breed and grow on the ground in known places seasons. Their paths can be tracked and predicted with a high degree of certainty. So, not knowing when they will invade and not having resources for their control cannot be an excuse.

In any case we have seen more planning and resources go into other, less predictable areas like crowd control. In some countries the equipment they have for this purpose is enough to repel an armed invasion.

Control of locusts and other pests would only cost a fraction of that. What is perhaps needed is the mentality that goes into anti-riot preparations.

The views expressed in this article are of the author.