The South African Bird Ringing Unit


Ringing birds around Africa!



Long-term demographic study of Black Sparrowhawks on the Cape Peninsula


Researcher/s: Ann Koeslag
Arjun Amar


Project Webpage

Species: Black Sparrowhawk (Goshawk) (Accipiter melanoleucus)
Location: Greater Cape Town area, Western Cape, South Africa
Running From: 2000 to present
Ring Type: Legring: colour combination
Colour Combination: 1 or 2 anodized (coloured) aluminium rings

NOTES:
To be able to follow the individual birds’ movements, and to be able to say who is partnering who, and how many chicks they raise, it was necessary to uniquely mark the individual birds. The only way to do this is to colour ring them.

Apart from the colour rings, each bird also has to have a SAFRING which is registered with the Animal Demographic Unit (ADU) at the University of Cape Town. These rings have a unique number so that if a bird is found dead or injured, or is trapped, the ADU can pass the information on to the ringer about where the bird was found.

Because we have only seven colours it has been quite a challenge to ring all the birds with unique colour combinations. When people observe birds and want to send ring combinations to us there are a number of things that we need to know in order to make an accurate identification:

The colours and which leg they are on. It is also important to note which colour is above the other.

As you can see in the pictures below, the bird on the left is ringed: purple over red on the right leg and SAFRING on the left leg.

The bird on the right has a different combination. It is ringed gold over SAFRING on left leg and blue on the right leg.

The other very useful information is a description of the bird: is it a white or black morph? If it is a black morph, does it have a white throat?

The hardest of all observations to make is, is it big or small? This helps us guess whether the bird is male or female. It has taken the people involved in this project many years to be able see a bird in the distance and to know which sex it is. Then it is the one on top that is the male.

So in summary: any information at all is useful.