Above: House Crow photographed by Francis Cherutich in Marigat near Lake Baringo on 3 January 2022
Published: May 2013 The East African Nation
News Alert: January 2022 – As predicted if no action was taken, the House Crow would spread into the interior in five to 10 years. It’s proved to be true as per the photograph above near Lake Baringo.
When David Livingstone – of the ‘Dr Livingstone l presume?’ fame arrived on the island of Zanzibar in 1866, he was so appalled at the filth and the stench that he called it ‘Stinkibar’ instead. Visitors sailing in could smell the island even before they caught sight of it. Epidemics were common – thousands died of cholera, bilharzias and chickenpox. In an earnest attempt to clean up the island, the colonial governor of the day who had served in India prior to his posting in Zanzibar, introduced the Indian house crow to clean up the filth, little knowing the havoc it would create in Zanzibar and beyond. That was in 1891.
“He had seen Indian house crows eating rubbish in India, so he thought it would be a good way to clean up the island,” tells Colin Jackson, conservation and science director at A Rocha, an international Christian organization engaged in scientific research, environmental education and community-based conservation projects around the globe. He’s also a research associate with the National Museums of Kenya.
“By 1917, the house crows were officially declared a pest in Zanzibar and a bounty put on their head,” continues Jackson. By then the bird had also hopped across to mainland Dar es Salaam and spread along the coastal shores from Djibouti in the Horn of Africa to Cape Town in South Africa. But its fast spread in the last two decades into the interior of Africa is even more worrying.
Cringing from the Crow
There are an estimated 51 species and subspecies of the crow, but the Indian House Crow has been called ‘the world’s most destructive crow.’ This aggressive monster is unafraid of humans and almost anything else, is a bully and very, very intelligent. In comparison, Kenya’s indigenous Pied crow is a welcome bird and once the title of a local children’s environmental magazine.
“House crows work in teams. While one crow distracts, the others in the flock steal,” continues Jackson. They compete for resources with other birds, predate on their eggs and chicks, and have been seen chasing gulls and terns 200 meters from shore. They regularly raid the poultry, chewing away the farmers’ profits. They are known to gorge out the eyes of infant cows, sheep and goats and are host to eight different human parasites. Research reveals they spread diseases by carrying and spreading bacteria like salmonella and E-coli, are carriers of cholera and typhoid
and may contaminate food and drinking water with their faeces.
It’s difficult to bait the house crow because they can recognize human faces. “If you shoot them, they will remember you and spot you a mile off. It’s the same if you set traps for them. They will learn them and avoid them. The same thing with poison. They won’t come near it.
“In large flocks they are a major pest and you don’t want them spreading inland otherwise they will be like the water hyacinth – difficult to get rid,” warns Jackson.
Challenging the crow
In the last two years, they have been seen in Voi and even more worrying in Mtito Andei having crossed the waterless Taru Desert through Tsavo. Thriving on human waste, they are perfectly at home where there’s lots of rubbish.
The only thing known to rid house crows is the avicide, Starlicide manufactured in America to get rid of the alien European starling, hence the name. It metabolizes after 10 to 12 hours, leaving no secondary or tertiary effects unlike the agro-pesticide Furadan that is used to lace bait and once ingested, animals like vultures and lions suffer painful deaths.
“The big advantage,” explains Jackson, “is that the bait can be set at night unseen by the house crows. They will eat it in the morning but die 12 hours later at the roost. The other crows don’t identify the bait.”
It worked well until the infamous 9/11 episode when the poison was banned for export by the Americans (citing that it could be used for other purposes other than pests) – and only allowed for import into a country with permission from the authorities. Since then, the house crow population along the coastal towns of Watamu and Malindi where populations are monitored by A Rocha have gone haywire.
In 2005, 30 house crows were reported in Malindi and six in Watamu. By October 2012, there were 5,000 in both towns.
The Kenyan authorities despite knowing of the impeding invasion, have taken no initiative to fight the menace.
The Tanzanian Tale
Meanwhile the Tanzanian government is out full force killing one million a month. The Tanzanian authorities are not too happy with the Kenyans for not taking any steps to kill the bird for flying across the border is no hardship for it.
“At this rate, it will take five to 10 years for the House crow to be all over the country,” is Jackson’s predicament. And like the water hyacinth and other invasive species that are on the rise in Kenya threatening its biodiversity and food economy, we will never be able to get rid of them but instead be imbued with the cost of fighting the pest.