LAST week, I visited a farm in Umguza, where the winter wheat crop is nearing maturity, but there was something very disturbing about how the farmer was controlling rodents and the menacing quelea birds.
He was poisoning or spraying them with a chemical called quelatox.
While this was the only way he could save his crop from these birds, there are traditional ways these birds could be controlled.
These ways are environmentally-friendly.
We all now know that the use of chemicals has far-reaching effects to the environment and other animal species as chances are high that they will ingest the poison in the food chain.
The most common way of controlling the birds has been large-scale spraying of infested areas, although environmentalists recommend other methods such as blowing them up using fire bombs, netting or dynamite at places where they roost, the use of flamethrowers has also been tried, with success.
According to the Natural Resources Institute, a UK-based development group, some 170 control methods are being tried in the southern African region with success, resulting in the killing of 50 million birds on average each year.
These methods included the most environmentally friendly ways of capturing the birds using nets at night on their roosting places and later killing them for food.
However, the Encyclopaedia of Pest Management notes that despite the annual destruction of millions of quelea birds by use of pesticides, damage has continued to increase annually.
Besides being only marginally effective, modern control methods also have serious negative environmental consequences.
Quelea flocks can consist of thousands of birds and since most small-scale farmers have no access to aircraft, fuel, chemicals, dynamite or flamethrowers, they can instead rely on age-old traditional methods that are more effective, and certainly more environmentally friendly, although hugely time-consuming.
Some of the traditional ways of controlling the birds are mainly through bird-scaring.
People go into the fields when their grain crop is vulnerable, using anything from catapults to banging pots and pans as well as noisemaking.
These are quite effective methods in the control of these menacing birds.
Over the years, farmers have been importing the toxic, quelatox chemical to kill these birds despite research showing how the chemical has far reaching environmental impact as it affects raptor bird species such as eagles, hawks and vultures that feed on the affected birds.
Environmentalists lamented that the chemical used may indirectly kill birds such as vultures which feed on the dead quelea birds.
They also cited other examples such as non-targeted species like insects.
While the immense damage the bird causes should not be underestimated, better methods that are harmless to the environment in reducing the number of bird colonies should be adopted.
Quelatox, falcolan and cyanophos are some of the internationally recognised chemicals used to control quelea birds as required by the Southern African Development Community (SADC) Agreement on controlling this bird.
The Plant Protection Unit of the Ministry of Agriculture organises spraying activities that are done at night when the birds have returned to their roosting sites that are usually along the riverine strip close to surface water.
In the process of spraying, there are likely to be spillages and residual spray falling on the ground surface.
The estimation is therefore that, a large percentage of the amounts sprayed do not reach their targets, thereby producing potentially negative effects on human health and the environment.
Sometimes these chemicals find their way into the water systems, affecting aquatic life in the process.
In Zimbabwe, the bird is common in Matabeleland South and North provinces, Manicaland, Mashonaland West/Central and Masvingo.
The bird has also reached Gwanda, Beitbridge, Umzingwane, Kezi and Plumtree but the Plant Protection Unit has managed to control it by urging farmers to use traditional methods to scare away the birds, including destroying their eggs or eating them as food.
For a number of years, subsistence farmers in sub-Saharan Africa have been at the mercy of the voracious red-billed quelea bird, as sky-blackening flocks of the tiny ‘feathered locust’ decimate fields across southern Africa, leaving most farmers with no alternative means to deal with the menace.
Nomadic super-colonies can grow to millions of birds, making quelea not only the most abundant bird in the world but also the most destructive. Although they prefer the seeds of wild grasses to those of cultivated crops, their huge numbers make them a constant threat to fields of sorghum, wheat, barley, millet and rice.
Quelea populations are notoriously robust; millions of birds are killed every year, but reducing their numbers has proved problematic as they are highly mobile, have few natural predators and breed extremely fast.
A new population can swiftly move into an area you just killed out and because they breed three times per year, with an average of three eggs per clutch, one pair of quelea birds can produce up to nine offspring annually.
The birds are long-distance migrants with a range covering well over 10 million square kilometres of Africa’s semi-arid, bush, grassland and savannah regions.
They have become serious pests in many African countries, stretching from South Africa, north through countries like Tanzania, Kenya and Ethiopia.
In countries such as Tanzania, traditional methods of dealing with the birds have been very effective.
The BaTonga and other indigenous people, who have intimate knowledge of medicinal plants, have effectively controlled pests such as the quelea by using environmentally friendly herbs or spraying chilli dust.