Known as the wild’s super cleaners, vultures play a critical role in the ecosystem. But with crippling threats like mass poisonings and harvesting for traditional medicine, the marking, tagging and tracking of these endangered birds are more important than ever. By Arnold Ras
Did you know that vultures can limit, to an extent, the spread of certain diseases? These birds of prey clean the veld of decomposing carcasses and in this way reduce the risk of disease. Perfectly adapted to their role as scavengers, vultures have keen eyesight (to spot carrion), limited plumage on the head (less to get fouled when feeding) and immunity to many wildlife diseases.
And yet vultures are under threat. Of the nine vulture species found in South Africa, four species are critically endangered (hooded vulture, white-headed vulture, white-backed vulture and bearded vulture) and two species are endangered (Egyptian vulture and Rüppell’s vulture).
Wild spoke to André Botha, manager of the Endangered Wildlife Trust’s Birds of Prey Programme and co-chair of the IUCN SSC Vulture Specialist Group, to find out more about the importance behind the marking of our vultures.
How do you go about tagging or ringing vultures?
We do both. We fit metal rings to the legs of vultures – these last for a long time. In other words, if the bird is recovered many years later for whatever reason, then we can determine where the bird was initially fitted with rings. This gives you a longer term data set.
With tagging we fit patagial tags, which are wing tags fitted onto the wing flap of the bird on the front of the wing. It is a much bigger tag and contains an alpha-numeric code that you can read from quite some distance. This enables us to identify individual birds to assess their movement, dispersal once they leave the nest, and their survival rate. With the proper modelling, you can also assess population sizes in a particular area.
Where is the marking implemented?
We have tagged birds all the way from Etosha National Park in the north of Namibia, Potberg (in De Hoop Nature Reserve) in the Western Cape, Eastern Cape, Southern KwaZulu-Natal, Zululand, the Lowveld and Highveld. So the whole of Southern Africa with the exception of Mozambique and Zimbabwe at this stage.
Which vulture species is currently facing the biggest threat and why?
The bearded vulture in the Maluti Drakensberg region. We currently estimate the population between 200 and 250 individuals at most, and approximately 92 to 100 breeding pairs. Very, very low numbers.
The birds are also confined to a limited area – the nearest population of the species that occurs outside Southern Africa is in Kenya and Ethiopia. There is a huge gap in terms of distribution. We are talking about an isolated population down here in the south that is under pressure due to a range of factors – some of the biggest threats being food shortage and poisoning. The highest number of mortalities over the last ten years was due to poisoning.
Why should our vultures be marked and monitored?
You get an idea of the birds’ movements, where they go to find food, and what some of the areas are that individuals or species focus on. By following their movement and specifically tracking them, you can also assess the height at which they fly, if there are specific routes they fly or specific areas they prefer to forage. That’s quite important in terms of drawing up sensitivity maps that can indicate where power lines or energy installations should rather be constructed and routed to cause less threat. In the case of poisoning we can focus our conservation interventions in specific areas. What we learn from the movement of the birds improves our conservation decisions and actions.
What can the public do to play a more active role?
People should be aware that these birds are under a lot of pressure. If you know of areas where vultures breed or if you are aware of active nests, limit your activity in these areas as much as possible. Take note of power lines in your area, be on the lookout for injured or dead birds under these lines and report them to us. We can then work with power utilities such as Eskom to make sure the lines are made safe and visible for birds. Also, if anyone is aware of poisoning incidents, immediately report it to conservation authorities.
When you spot a marked vulture, dead or alive, send an email to [email protected] or [email protected]. Alternatively, phone the South African Bird Ringing Unit (SAFRING) in Cape Town at +27 (0) 21 650 2421/2. Remember to provide your name and contact details.
Record this information
- Date and time
- Place (GPS coordinates if possible)
- Condition of the bird
- Type of marking device (leg ring, patagial tag or tracking device), colour of the device, device’s alpha-numeric code (if visible), and where on the bird’s body the marking device is attached
- Take a photograph if possible