Teme Valley Musings, March 2021

by Stephanie Mocroft

The photograph accompanying this month’s article is of a bush cricket. It hopped, or maybe flew, in through my open window last year, apparently to inspect my curtains. A handsome creature, it has only fairly recently hopped or flown into Worcestershire and is called the Roesel’s bush cricket. It is not the subject of this article though, which is about locusts, but as I have never had the opportunity to photograph a locust I hope you won’t mind me using it instead.

I was prompted to write about locusts because I spotted an article in the paper about a Herefordshire company which supplies equipment and expertise to help control locust swarms in Africa. It was in the news because this vital work had been interrupted by coronavirus travel restrictions. The company makes spray equipment for planes, helicopters and trucks and assists the UN Food and Agriculture Organisation’s programme for locust control.

The locust in question is the desert locust and is found in65 countries,most of which lie between West Africa and India. Normally it lives a solitary life, but after heavy rain it has the potential to breed extremely rapidly.In the right conditions huge numbers can develop simultaneously,these thenriseupand forma swarm. It is difficult to imagine the size of a swarm, because it may contain 40-80 million insects,cover an area of 460 square miles andfly a distance of 80 miles in a day.

Last year Kenya experienced the worst locust swarms for 70 years. A swarm the size of one square kilometre can eat enough crops to feed 35,000 people for a year, so the threat to food supplies was great. The present outbreak began during cyclones in 2018 followed by heavy rain and warm weather in 2019 which helped it to spread quickly. War in Yemen and Somalia prevented early control measuresfrom being used, then coronavirus hampered later interventions. Although there are biological controls, using a type of fungus to kill developing insects, these are ineffective in the later stages of an outbreak so the main action at the moment is to spray with insecticide.

Usually, control is affected by prompt action at an early stage of the insects’ development and by monitoring weather patterns against historical outbreaks to try and predict swarms. A plague of locusts is just as devastating today as the Biblical plagues in the time of the pharaohs. A tenth of the world’s population lives by subsistence farming in the countries under threat and often there is insufficient money for bio- or conventional pesticides or for the aircraft that are used to apply them or for the control centres that monitor them. Last year the added pressures of political and natural disaster caused a crisis within a crisis.