ACTIVITIES

The DLCO-EA has a regional and an international reputation in sustainable management of migrant pests. This often results in the prevention of, or reductions in, pre-harvest crop losses, pasture denudation and therefore to increased food security; while Tsetse control, leads to improved human and livestock health.

The following examples of economic losses caused by migratory pests in Eastern Africa, can be cited :

Desert locusts

An adult locust eats the equivalent of its own body weight of vegetation (leaves, flowers, seeds, etc) per day, which is approximately, 1.5-3.0 grammes.

1. During plague situations..
   
   
   • A swarm of Desert Locusts can contain 50 million individuals in a square kilometer of cropland, pasture, forest or agricultural irrigation scheme.
     
     
   • A small swarm of 1 sq.km can eat 100 tones of food per day.
     
     
   • Half a million adult locusts can consume two tones of crops and other vegetation per day, for 30-180 days.
     
     
   • A medium-sized locust swarm can consume 80,000 tones of green vegetation or crops per day, enough to feed a population of 100,000 persons for a year.
     
     
     
2. Plague situations vary in duration and geographical extent, but have, since 1908, ranged from 7-13 years, and alternated with short periods of population recession lasting up to six years.
   
   
3. The latest major upsurge in 1985-89, for example:
   
   
   • Affected some 43 countries and covered Africa from the Cape Verde Islands in the Atlantic to the Red Sea, and across the Middle East to Pakistan and India.
     
     
   • The resulting outbreaks were controlled over some 5.5 million hectares in the Sahelian countries of Africa, including Sudan, Eritrea and Ethiopia.

African Armyworm
(Spodoptera exempta Walker )

• Infestations by larvae vary in size, from less than one hectare to several hundred sq. kilometres.
  
  
• A full-grown larva (caterpillar) can eat some 0.7 to 2.0 grammes of young leaves and stems of cereal crops (Maize, Sorghum, Millet, Rice, Wheat, Barley, Teff), sugar cane seedlings, etc. and grasses per day for 1-2 weeks of its adult life; while larval density can range from 10 to 1000/sq.metre.
  
  
• The effect of Armyworm damage (i.e. defoliation) in pastures and rangeland can last 5-8 weeks (1.2 months) before full recovery, which affects small scale farmers, and depends on rainfall, etc.
  
  
• Livestock feeding on grass which is heavily infested by the larvae, have been known to die from some kind of poisoning, e.g. in southern Ethiopia (Borana), Somalia and Kenya (Maasi), and parts of Southern Africa.

Red-billed Quelea or Weaver Birds
(Quelea quelea Linn.)

Quelea male in breeding plumage attacking a millet head.

Each adult bird can consume 3-5 grammes of grain daily, and wastes about 10 times this amount. Consequently, an individual bird can cause damage of 7-10 grammes of grain per day; thus 1 million birds in a single roost can destroy 7-10 tones of grain per day.

• Because of gregarious nature, Quelea birds often move in flocks of hundreds of thousands or millions.
  
  
• Quelea birds normally feed on wild grass seeds and cultivate crops (e.g. wheat, rice, millet, sorghum, etc.), and insects, which they feed to their young (nestlings).
  

The following activities are therefore routinely carried out by the organization for the benefit of the small-scale and large-scale crops and livestock farmers in Eastern Africa:

Migrant Pest Surveys, Monitoring and Forecasting

The overall aim is to survey, monitor, document and map out possible seasonal migrant pest breeding sites to prevent outbreaks of Desert Locusts, Armyworm and Quelea birds from developing into more severe plagues that cause famine, etc.

Migrant Pest Control

The strategy is to strengthen national efforts in reducing the threat of migrant pests by detecting their developments and controlling them.

The DLCO provides technical guidance on cost effective and environmentally sound methods of controlling these pests including the use of aircraft fitted with sprayers.

DLCO-EA Spraying Aircraft on duty.

Training/Manpower Development

The aim of this strategy is to increase self-reliance in the region by training crop protection personnel in the various aspects of migrant pest management.

The Organization offers training to individuals and groups both within and outside the DLCO-EA region. Specialist staff of the organization also provides on request consultancy and advisory services in integrated migrant pest management.

Participants of Quelea & Armyworm Consultative Research Forum
held in Garden Hotel, Machakos on 20 th - 23 rd March, 2000.

Scientific/Applied Research

The Division has responsibility for advising the Director on scientific matters. It is made up of Insecticide Research to achieve effective control with less contamination of the environment; Bi0-control Research to integrate e.g. the application of Fungal Pathogens in the control of locusts and grasshoppers; Spray Technology, to improve delivery systems; and Quelea and Armyworm research, e.g. to detect mass developments and apply strategic control at source.