Experts have warned that the Kenyan government’s efforts to kill up to 6 million red queleas that have invaded farms will have unintended consequences for the birds of prey and other wild species.
Continued drought in the Horn of Africa has reduced the amount of native grass, the seeds of which are the main food source for birds, causing birds to increasingly invade grain fields, endangering 2,000 acres (800 ha) of rice. The birds destroyed about 300 acres of rice fields.
According to the Food and Agriculture Organization (FAO), a single kelly can eat up to 10 grams of grain per day. Farmers in western Kenya could potentially lose up to 60 tons of grain to birds. In 2021, the FAO estimated crop losses attributed to birds at around $50m (£40m) a year.
Spraying fenthion, an organophosphate pesticide, was the preferred method of pest control in Africa, but researchers described the chemical as “toxic to humans and other non-target organisms.”
The authors concluded, “Fenthion can indiscriminately harm or kill, with consequent adverse effects on non-target organisms.”
Paul Gacheru, species and site manager for Nature Kenya, a local subsidiary of BirdLife International, said the method used to control quelea should be well-informed because “widespread use of non-targeted avicides can lead to environmental pollution and mass mortality to others.” Birds and animals.
“Often, there is poor post-spray management, which increases the risk of toxin-related wildlife deaths, especially among scavenging animals – hence the need for enhanced education and awareness on chilea control.”
With an estimated breeding population of 1.5 billion birds in Africa, ornithologists say there are not enough birds of prey to wipe out vast colonies of quillia nor effective, environmentally friendly solutions.
A culture of ensuring human food security above all else will be amplified “because of what we now see as a possibility, due to climate change, as open grasslands that used to be fed with keleas. Lands are rapidly becoming farmland,” said Simon Thomsett, director of the Kenya Birds of Prey Fund.
Thomsett added that in Kenya’s wheat-growing areas, farmers spray any type of bird deemed a threat to farms, “however some birds prey on the insects that feed on their wheat.”
But it’s the effect of pesticides on the few remaining birds of prey that worries him most. “Those on the conservation of birds of prey side of the fence are very worried about spraying. Today, all birds of prey [in Kenya] in danger. Anyway, how effective has spraying been over the past 60-70 years? “
The Food and Agriculture Organization and the United Nations Environment Program jointly administer the Rotterdam Convention, whose goals include reducing risks from hazardous chemicals in agriculture. They have been considering listing fenthion in Annex III to the treaty, which is a list of pesticides and industrial chemicals that are banned or severely restricted for environmental or health reasons.
A report by Robert A Cheke of the University of Greenwich that was used as a working document at a 2017 FAO workshop in Sudan recommended alternatives to the use of the chemical, including a predictive and control planning method.
“If the efficiency of control operations can be improved, then the amounts of fenthion used can be reduced. One way to improve the efficiency of control strategies is to detect through satellite imagery the presence of suitable breeding areas for kelia… or to predict where the birds are likely to breed,” the report said.
She added, “Given that bird migrations and breeding opportunities are determined by rainfall patterns, it is possible to put in place forecast systems to predict where birds are likely to breed, and thus focus activities in search of colonies in areas where birds are likely to be.”
Quelea infestation occurs frequently in many African countries. Six months ago, FAO issued $500,000 to the government of Tanzania to support insecticide spraying, monitoring and capacity building after 21 million kilolia invaded fields of rice, sorghum, millet and wheat.