In the 1940s, before systemic insecticides became readily available, desert locusts, the
ones he has encountered in the northern Sudan - or to be more precise, their hoppers
- were indeed killed with a bait of Paris Green mixed with bran. Paris Green, I was told
by Mr Arthur Staniforth, is sodium arsenite. This mixture was referred to by Somalis as 'sun' or
poison, which indeed it was. Livestock inevitably ate some of it and it killed them.
I first got involved with locust control in what was then the British Somaliland
Protectorate, and is now the, alas unrecognised. Republic of Somaliland, in the early
1950s. I was an agricultural officer who for his work had to trek extensively in the
farming areas; we walked or rode horses or mules, always off what passed then for roads
in the farming areas and therefore knew all the areas where crops were grown. Whatever
the farmers wanted to take to market went on camelback, not carts, and therefore not
having roads was not a major problem - then.
By the 1950s the bait for controlling desert locust hoppers was gammexane, not Paris
Green, mixed with bran. We spread it where either we knew that the adult locusts laid
their eggs, or where hoppers were spotted by patrols. This mixture did not hurt livestock.
However, for many years there was considerable objection to its use by the pastoralists.
All of us who were called upon to spread it had actually to eat some of the mixture while
being carefully observed by the people, to demonstrate that it is not poisonous to humans
and animals, before they allowed us to spread it. Baiting did not control the adult locusts,
who flew and settled to feed on vegetation above ground level - on trees and the growing
crops which could not be baited. They laid their eggs and the inevitably escaping
hoppers matured and provided hoppers for the next outbreak.
By the mid-1950s, a Desert Locust Airspray Unit was established. The planes,
carrying a powerful insecticide which, as must be emphasised, did not harm any warmblooded
creature, flew off at first light when the locusts were settled on trees and on the
ground and could not fly because of the dew on their wings. The places where they
settled for the night were spotted by ground patrols or by late afternoon reconnaissance
flights. This was a most effective control. By the late 1950s the desert locust ceased to be
a major problem. But this did not, and cannot in the future, last forever.
The desert locust has a gregarious and solitary phase. When in the latter phase,
numbers congregating are limited and while naturally eating green vegetation they are not
numerous enough to be a menace. While they do not form swarms, they become a core
for a future outbreak when they turn into the gregarious phase. All this is contained in
their scientific name - Scitsocerca gregaria. They turned gregarious, i.e. formed swarms in
1978 and I am told, but have not been able to obtain details, also more recently.
In 1978, by which time I was in the World Bank in Washington, we experienced the
first serious outbreak since the 1950s. One day my boss’s secretary came running into
my office with an armful of books. She told me there was to be a meeting on desert
locusts in about 5 minutes in an office some 10 minutes away from mine and the boss (an agriculturist who had spent all his pre-World Bank time in West Africa where the
desert locust was unknown) wanted me to attend it in his place: he guessed that since I
worked in the dry parts of East Africa in the 1950s I might know something about them.
The secretary did not permit me to read the armful of books before I left, and would I
At the meeting I explained how I got there instead of my boss. The Chairman opened
the meeting: “Gentlemen, we are here to discuss the problem of the desert locust. There
has been a new outbreak. Has any of you ever seen one?” Deadly silence. None of the
people in the room had served in the dry parts of Africa in the 1940s and ‘50s. I said, “I
have seen about a thousand million of them and plead guilty to murdering very many”.
Excellent, would I please tell them all about it. I told them what I remembered;
fortunately I managed to recall the names of two experts who have done much research
on them and have published papers. The Bank financed the revival of the airspray unit.
They were successful and I have not heard of desert locust problems for many years, but
I am told there has been a recent outbreak.