Zandvlei Trust

Western Cape Raptor Research Programme – Andrew Jenkins

Andrew has been busy!!

photograph by Andrew Jenkins

This pair were two chicks Andrew ringed in 2005, one from a nest in Scarborough, the other from the Muizenberg area.

photograph by Andrew Jenkins

The dead bird was a female he ringed in 2004 in the Muizenberg area. She died when she flew into this 8mm thick plate glass window of a house on the slopes of Camps Bay.

photograph by Andrew Jenkins

The 3rd picture is of a chick Andrew ringed in 2005 in Fish Hoek, perched in a tree in Muizenberg.

photograph by Andrew Jenkins                                                                  photograph by Andrew Jenkins

These 2 pictures of a chick ringed on Table Mountain and then a few months later as a fledged juvenile in the Rondebosch area.

           photograph by Gary van der Merwe

See the expedition to help a pair of Peregrine Falcons to breed in the suburbs.

Andrew's earliest recollection of his interest in birds is as a small boy he watching a Mallard Duck that used to frequent a stream that ran through his grandparents home in the UK. Soon that gave way to a lasting fascination with Peregrines, long before he actually saw one of these impressive raptors. He attributes his awakening interest in Peregrines to the controversy that surrounded the use of DDT in the UK at the time and the adverse effect it was having on these birds that were considered very rare at the time. When his family emigrated to South Africa, they often went on holiday to the Drakensberg. Andrew's interest in raptors grew and as a young schoolboy he used to monitor a pair of Black Eagles that were breeding at Hartebeespoortdam. After his schooling in Johannesburg he did his undergraduate studies in Zoology at the University of Natal (Pietermaritzburg) and completed his PhD at UCT and currently serves as a research associate at the Fitzpatrick Institute, managing and overseeing a suite of projects that make up the Western Cape Raptor Research Programme.

During these years Andrew was fortunate to meet and work with several individuals who influenced and guided Andrew's growing interest in raptors.
As a schoolboy he used to assist Chris Brown, an ornithologist, with radio tracking vultures in the Drakensberg. Chris later moved to Namibia where Andrew assisted him with various raptor projects. Chris currently heads up WWF in Namibia.
Dave Allan, the Curator of Birds for the Durban Museum, whose published work on raptor surveying of the Transvaal, is today still an excellent example of what can be achieved through hard work and dedication. Dave was instrumental in getting Andrew into the Fitzpatrick Institute as a student to do Peregrine work, when he was doing his Masters there. His PhD dealt with comparing the biology of the Lanner and Peregrine falcons.

                                                photograph by Andrew Jenkins
Lucia admiring the peregrine while helping Andrew. It is patiently
awaiting release after its details have been recorded.

Peregrines have a more specialized way of catching their food and as a result are more dependant on the abundance of their specific food type, birds, and the environment in which they are found.
Currently 35 Peregrine nests have been recorded in Andrew's study area, which stretches from Cape Point to the Tygerberg Hills. 22 of these occur in the mountains, 8 on buildings and 5 in quarries. Andrew expects approx. 30 chicks to fledge this season. So far 24 have been ringed. 
This year has been a relatively poor breeding season for Peregrines. This is mainly due to late cold fronts with torrential rains in October. Rain squalls provide gaps for the birds to dry out and catch some food. During downpours of torrential rain, birds get sodden. This is detrimental to the incubation process and limits the adult's ability to protect a newly hatched chick from the cold wet weather.
The variation in numbers of chicks produced, between good and bad breeding seasons is quite substantial. A good season produces five times the number of chicks. IOW 35 pairs of Peregrines, in a good season can produce between 70 to 80 chicks. In a bad season, only as few as 20 chicks.
Peregrines are also susceptible to high speed collisions. 60 to 70% of casualties are due to high speed collisions with overhead wires, vehicles etc. So although Peregrines are able to exploit the benefits presented by urban areas, it holds many hidden dangers for them. As a predator at the top of the food chain the use of poison has fatal consequences for Peregrines.

Anecdotes.

Andrew was at a Peregrine nest wearing his Electric Eagle Project cap, sporting a Martial Eagle as the logo. It seems the female peregrine took an instant dislike to the cap, because she swooped down, gabbed the cap off his head and disappeared around the corner with it. Upon reappearing the cap was gone!
One year the Athlone Power Station was due to undergo maintenance work during the breeding season. In order to prevent the Peregrines from breeding there, the nest boxes provided for this purpose, were turned around and placed up against the wall. When Andrew returned from a trip upcountry to check on the Athlone Power Station Peregrines, he found that the determined pair of Peregrines had found a gap between the wall and the nesting box and had gone ahead with their breeding. Luckily, maintenance was rescheduled to allow the chicks to fledge. The Athlone Power Station Peregrines produce between 3 to 4 chicks every year, but so far records show that very few are recovered back into the Peregrine population of the Cape Peninsula. Another interesting fact about these Peregrines is that they have a choice between three nest boxes and they only alternate between two of them.

                                                           photograph by Andrew Jenkins
A Peregrine Falcon on her nest.

An argument for a balanced approach to alien tree and plant eradication.

The removal of alien trees is another factor that may affect the raptors who have adjusted the spread of their environment accordingly. There is a certain amount of concern about the drive to eradicate alien trees without giving the effects it might have on these raptors. Is it a desirable outcome to reduce them to a species living in perilous conditions?
On the Peninsula alien trees have replaced the natural forested areas. Commercial forests and invasive tree species have opened habitats for predators in a system where they don't belong.
Take the Breede River for instance, where alien vegetation and alien trees occur. The river is full of alien and invasive fish resulting in a totally synthetic system.
The Fish Eagles predate on the fish and the trees provide suitable nesting sites. The Black Sparrowhawks, who also find the alien trees suitable for nesting, predate on all the smaller birds who come to the area to eat the fruit grown on farms. In this way an entire synthetic system has been created.
Do we now want to take away the trees and loose the Fish Eagles?
Do we want to loose the Black Sparrowhawks, who assist the fruit farmers by keeping the fruit eating birds in check? 

Andrew Jenkins, (021) 650 4123/4 or 082 959 9238   andrew.jenkins@uct.ac.za