According to new research from CABI just five invasive species are causing up to US$0.9 – 1.1 billion in economic losses to smallholder farmers across six eastern African countries each year, equating to 1.8% – 2.2% of total agricultural GDP for the region.
These losses are expected to grow to $1.0 – 1.2 billion per year over the next 5-10 years, highlighting the urgent need for coordinated responses at regional, national and international levels.
Horticultural crops, often grown along with staples such as maize, are valuable nutritionally, but also as cash crops that can be an important route out of poverty for smallholder growers. A number of invasive species affect horticultural crops and this study included three species of Liriomyza leaf-mining flies, which attack a variety of important crop families including ornamental plant species and vegetables. In this study, impacts on beans and peas were considered, with total annual losses up to $149.1 million.
The South American tomato leaf miner, Tuta absoluta, has had a devastating impact since its recent introduction to Africa, frequently causing total crop loss and leading to three-fold increases in tomato prices. Losses to eastern African smallholders are estimated at up to $79.4 million per year at present, but this figure is expected to grow substantially with the rapid spread of this pest.