The earliest major locust invasion in colonial Kenya was in 1928.
First seen in February, they entered Kenya from Turkana and flew southwards along the Kerio Valley, stopping here and there to breed and feed.
They soon reached Uasin Gishu Plateau and Trans Nzoia, where they sojourned temporarily before proceeding on their southward journey into Tanzania.
They then made a northward and north-westward turn from Tanzania through Maasailand.
They also spread to other parts of the country such as Laikipia, Nyandarua and Voi.
The swarms left evidence of their work wherever they sojourned: dilapidated fields and hatched hoppers which caused further havoc, continuing well into 1929 and 1930.
The new wave of invasions in 1931 and 1932 were by the more voracious and destructive tropical migratory locusts.
Possessing a strong preference for graminaceous plants like millet, finger millet and maize, these locusts migrated from the upper reaches of River Niger and invaded Kenya from the direction of Uganda via Bungoma.
They moved southwards into Tanzania, before making a reverse flight towards the southern and western shores of Nyanza Gulf.
A large section of the swarms had moved across the Rift Valley towards Central Province and the Kenyan coast.
They devoured most of the plants and other vegetation, breeding and flying in huge swarms, usually covering a few miles wide.
The damage caused by the 1931 locust invasion was quite extensive. Available reports only cover the period up to June and the end of August 1931.
In the colonists areas, losses of maize and wheat were as follows: Nzoia Province (50 per cent), Nyanza Province (70 per cent), Rift Valley (25 per cent), and other areas 10 per cent.
African reserves made the following losses of grains including millet and maize: Bungoma, Kakamega and Busia (10 per cent), Kisumu, Siaya, Kano and Nyakach Central (15 per cent), Gusiiland and Luoland in southern Nyanza (50 per cent), Kericho (50 per cent), and Kikuyu (15 per cent).
These figures represented a money value of not less than £175,000 for maize alone.
Damage to wheat, sugarcane and small grain crops may be taken at not less than £75,000 (Sh9.9 million). Additionally, large quantities of grazing in all areas were destroyed.
So widespread and virulent was the resultant famine wrought by the pests that the Luo and the Luhyia named children born at the time Nyangweso, the name for both the locusts and the famine.
AREAS OF FOCUS
Kalenjin communities, particularly in Keiyo and Marakwet, referred to the period as Kenyeitab bichotit or kiberer.
When locusts first appeared in 1928, the colonial authorities first required the following information to provide the basis on which to act: the exact places infested by locusts; the approximate acreage covered by the swarms; whether they were hoppers or flying locusts; the direction of their movement, and their breeding places.
It took some time before H. Wilkinson, the assistant Entomologist in the Department of Agriculture, received the necessary information which he quickly communicated to agricultural and administrative officials.
Administrative and agricultural officers, scouts, the public works department, railway workers and African labourers were deployed to combat the locust invasion.
Facilities including motor trucks, petrol, arsenate soda, tents and other camp equipment, sprayers, pumps and drums were bought.
However, more concerted efforts to destroy the locusts took place on European farms.
They included killing hoppers by beating them, digging trenches and driving hoppers there, driving locusts into brushwood piles and burning them there, driving stock to trample over them and to force them to fly away, trapping them, spraying both hoppers and locusts with arsenate of soda, and digging up and destroying locust eggs.
In contrast, in African reserves, chiefs ordered the manual destruction of hoppers to mitigate their maturation to full grown locusts.
The government claimed financial constraints and stated that spraying locusts in African reserves would be harmful to Africans.
In the end, colonial anti-locust campaigns were also assisted by forces of nature.
Wilkinson found out that locusts and locust eggs were attacked by parasites, notably the nematode worm of the Mermithidae family.
SOURCE OF FOOD
In many areas, birds also feasted on the locusts. African communities, particularly in western Kenya, captured, dried and stored the locusts as a delicious source of food.
Locust invasions recurred in the late 1930s and 1940s, forcing governments in East Africa to establish a locust control body to better manage the menace.
The ongoing locust invasion demonstrates that the menace persists and that the government should make its early warning system and other practical ways of combating it a lot more efficient.
Prof Ndege teaches history at Moi University