| Predators, farmers and biodiversity | |
|
 It’s a first for South Africa and it is also one of the largest camera trap surveys ever undertaken in the world. Starting in September 2012, 180 camera stations have been set up over an 80 000 hectare area, spanning 17 sheep farms in the Laingsburg-Beaufort West district of the Karoo.
The camera traps are being used as part of a three-year research project into the
effect of predators on sheep farms, combined with a biodiversity assessment of the area. Smaller assessments have been done on individual farms but never on this landscape-level scale.
During the course of the project – which is being funded by the WWF Nedbank Green Trust
and managed by the University of Cape Town’s Sustainable Societies Unit in the Centre for Social Science Research (CSSR) – a way forward for Karoo farmers besieged by predators will hopefully be found.
“Karoo sheep farmers are losing livestock to jackal and caracal at unsustainable rate. They
are forever being told to stop persecuting predators and at the same time they are being told to produce food. We need to understand exactly what is happening on these farms from an holistic perspective, including an assessment of predators, farm management and the general biodiversity status of the area,” says behavioural ecologist Professor Justin O’Riain of the University of Cape Town’s Department of Biological Sciences who is partnering on this project with the CSSR.
In the field is Marine Drouilly, a PhD student O’Riain is supervising. An incredibly hard-working
researcher who is passionate about the project, by February this year she had surveyed a large area of farms in the project using the 180 camera traps, which are spaced two kilometres apart. This survey resulted in a huge number of photos of many different species.  PhD student Marine Drouilly and Peter Gouws whose family farms in the project area, setting up a camera. “The findings will be released in a few months’ time, but preliminary observations indicate that small livestock farming in the Karoo supports a healthy diversity of wildlife. Blanket statements that this agricultural sector is the greatest threat to biodiversity is simply not supported by the data,” says O’Riain.
Drouilly will now compare the data with data she is gathering in the Anysberg Nature
Reserve – one of Cape Nature’s reserves southwest of the project farms. There is a strong perception that nature reserves and game farms provide refuges for jackals. “She is currently repeating the grid of camera traps here, and she will be able to compare the biodiversity and predator density in this area where there is no grazing impact and competition from sheep to that of the farms in the project area, as well as what the predators in the respective areas eat,” O’Riain explains.
Another dimension of the project is the catching and collaring of jackals and caracals, and the
use of satellite technology to understand how they navigate the landscape, how they respond to so-called jackal proof fences, what is the size of their home range in farming areas versus the natural control areas and if there is a difference, why this is – is it because there is more available prey or is to do with the presence of the apex predator, the leopard, in the reserve?
“We also want to establish what they eat and where they drink,” continues O’Riain. “There is a
strong sense that the movement into the Karoo of these predators over the past couple of decades could have a lot to do with the establishment of permanent water on farms and in nature reserves as jackals need access to permanent water sources.
.
The project area in the Karoo. “Historically, many species including jackals would have moved in and out of these areas in accordance with the Karoo’s unpredictable rainfall. The provision of permanent water may thus have changed the ranging patterns of many species.”
Six jackal and six caracal are being collared in the Anysberg Reserve and the same numbers in
the farming areas in order to follow and compare their daily movements and their hunting and dietary behaviour. The researchers want to understand the spatial and behavioural ecology of predators in these markedly different land use areas.
“We have asked the farmers for permission to catch and collar on their farms and to allow these
collared individuals to remain in the area and they have obliged,” says O’Riain.
“This level of cooperation is unheard of,” says Associate Professor Beatrice Conradie, Director of
the Sustainable Societies Unit and agricultural economist on the project.  Anysberg Nature Reserve “We enjoy the support of the entire community. The ecological work is focused on a core area of 80 000 hectares of continuous farmland but a concurrent management survey covers about three quarters of the land in the district.”
The purpose of the management survey is to investigate the levels and determinants of the
profitability of sheep farming.
Laingsburg is a very marginal area. Rainfall is in the order of 120 to 130 mm per year. The
average flock size is 642 ewes, but a quarter of flocks consist of less than 300 ewes each and half the farmers have an income similar to that of schoolteachers.
“We don’t know what the best management practice for predators will be at this stage. What we
are offering is sound collaborative science from which we can then discuss the way forward. I suspect that some form of control will be necessary but how and what is the bigger question that needs to be addressed after we have concluded the baseline research.
Non-lethal alternatives are a hard sell since many farmers believe that culling is an integral part of
the way forward. However, after analysing hunting club data from the 1970s Conradie arrived at the paradox that the more predators are killed on a given farm, the more stock losses rise.
“What is special about this project is that we are talking to each other about these issues,” says
Conradie. “What is at stake is farmers’ entire livelihoods but also the livelihood of the entire local economy. If agriculture disappears, Laingsburg only has the N1 and that is not enough to maintain a viable town.”
Regarding the biodiversity assessment part of the project, the team would like the project area to
be compared to, for example, the wheatland area around Caledon in the Western Cape, where they would like to repeat exactly the same camera grid and research format.
“Many people don’t think of the wheatlands or winelands as having an impact on biodiversity because
there was such massive impact on biodiversity historically that much of the biodiversity in that region has been lost,” says O’Riain.
“It’s very possible therefore that despite all the finger-pointing at livestock farmers, they could well be
far better custodians of biodiversity than many other forms of agriculture. This project might prove this. It might also reveal that grain eaters have a substantial biodiversity impact that is potentially higher than that of meat eaters.”
Alongside the predator data, these are some of the fascinating and potentially contentious findings with
which the project team is working. We look forward to the findings and will keep you posted.
SOURCE:NedBank
|
No comments:
Post a Comment