House crow invasion of Cape Town... halted by partnerships
Partnerships are crucial to improving the management of invasive species. Since 2009, the City of Cape Town Invasive Species Unit (ISU) has maintained a superb working partnership with the National Department of Environmental Affairs’ (DEA) Natural Resources Management Programme (NRMP). The aim of the partnership has been to control the invasive Indian house crow (Corvus splendens) population in Cape Town and to prevent the establishment of new roosts.
House crows or Indian house crows are listed in the National Environmental Management: Biodiversity Management Act 10 of 2004 (NEMBA) Alien and Invasive Species (AIS) Regulations as Category 1a invasive species. This means that the law requires the ISU to control and remove the house crow population in the City of Cape Town.
Since the launch of the Cape Town ISU House Crow Control Programme in 2009, the population of house crows in Cape Town has been reduced from over 10 000 birds to less than 300 birds.
As a innovative job creation project for marginalised Capetonians, this invasive species bird removal project owes its success to funding from DEA NRMP.
Since 2015, the City of Cape Town ISU has also been able to track the movements of the invasive Indian house crow between the Cape Town harbour and the city’s Central Business District (CBD).
This is thanks to a successful 2015 partnership between the City’s ISU and the Transnet National Ports Authority (TNPA), whereby the ISU has been allowed access to the Cape Town Harbour.
History of house crow invasion in Cape Town
House crows first arrived in South Africa in the early 1980s. They are regarded as one of the world’s top 100 - most damaging - invasive species.
House crows are “hitchhikers” travelling by ship from their native range of India, Pakistan and Burma to countries where they do not naturally occur, such as Tanzania, Mozambique and South Africa. A recent BBC feature showed the detrimental impact of a house crow invasion on the city of Mombasa, Kenya.
The City of Cape Town has a better chance of winning the battle against house crows, if we are able to prevent them from entering the country.
The ability to monitor the birds from the harbour affords the Indian house crow team a better chance of detecting house crows that may enter or exit the country.
This control programme is a true example of how partnerships are necessary for sustainability best practice.
Why are house crows an invasive problem?
Indian house crows...
- Are aggressive, opportunistic feeders.
- Have a negative impact on indigenous bird and animal populations, agricultural crops and domestic poultry.
- Pose a health hazard to humans as they are carriers of enteric (intestinal) diseases that are transmitted through their beaks or claws.
- Preys on eggs and nestling of native birds, also eat small native animals.
- Mob humans and pets.
- Occasionally destroys vegetable gardens in informal settlements.
- Are a vector for pathogens that cause cholera, typhoid, dysentery and salmonella poisoning.
Download an identification pamphlet on Indian house crows in Cape Town. Click here
- See pdf attachment at the base of this feature).
How can you help?
Residents who want to participate in reporting house crows, can join Cape Town Invasives on Facebook: www.facebook.com/ctinvasives
NOTE: Invasive Indian house crows should not be confused with indigenous Cape crows or pied crows, the latter of which are very common in many suburbs of Cape Town. The indigenous pied crows are the only crows with a white breast, whereas the indigenous Cape crow is black in colour and is larger than the invasive Indian house crow.
- Invasive House Crow ID Kit for Capetonians (270 Downloads)