Impacts of power infrastructure
Over the last few years the Fitz has been involved in projects to mitigate the impacts of power generation and transmission infrastructure. Initial attention was focused on collision impacts associated with powerlines, which mainly affect large, open-country birds such as bustards and cranes that are unable to react rapidly when they encounter aerial obstructions. More recently the project has considered the impacts of renewable energy technologies, including wind and solar power generation.
Wind and solar power generation have much less broad-scale environmental impact than the coal-fired power stations on which South Africa relies for most of its power generation, but both technologies can have significant impacts at a local scale. The aim of this programme is to provide practical solutions to reduce the impacts of renewable energy projects, as well as energy transmission infrastructure, on birds in southern Africa. The programme, which is run in close collaboration with BirdLife South Africa’s Birds and Renewable Energy programme, received a considerable boost in 2016 with the awarding of a grant from the Hans Hoheisen Charitable Trust to fund a full-time research assistant for three years. Vonica Perold, a former field assistant on Marion Island, was appointed to this position from August 2016. A presentation to the ABAX Foundation in December 2016 also resulted in further funding to model the impacts of wind farms on Verreaux’s Eagles Aquila verreauxii. Progress on this latter project is reported separately in the section “Conserving Verreaux’s Eagles”.
Activities in 2017
- Gathering of field data from the large-scale experiment to test the efficacy of transmission line marking (using flappers or static flight diverters) to reduce collision mortality finally came to an end 8 years after it was initiated as part of Jess Shaw’s PhD on mitigating powerline collision risks for large birds in the Karoo. This study, set up in the De Aar region of the eastern Nama Karoo, was a partnership between ESKOM, the Endangered Wildlife Trust (EWT) and UCT. Jess, now based in Scotland, and former post-doc Tim Reid, now based in Australia, completed analyses of the collision data to show that marking lines reduces collisions of Blue Cranes Anthropoides paradiseus, but has no significant benefit for Ludwig’s Bustards Neotis ludwigii. Jess is preparing a paper for publication on this very important experiment.
- CB MSc student Sydney Davies worked with Tanya Smith (EWT) to analyse the first 1-2 years of accurate GPS-GSM tracking data collected for Blue Cranes in the Overberg. The aim of this project is to better understand how cranes move in this region, which is home to the world’s largest population of this species. Collisions with powerlines remains a key concern for cranes in this region. Sydney found considerable variation among individuals. Non-breeding birds tend to have larger home ranges than breeding birds, but this is not always the case. Some adults greatly reduced their home ranges while breeding, while others actually ranged further while breeding. We plan to expand this project into the Swartland, where former CB MSc student Julia van Velden found that there are more conflicts between cranes and farmers.
- Vonica Perold worked with Sam Ralston-Paton (BLSA) to review the first two years’ of bird mortality monitoring at wind turbine facilities around South Africa. They are currently finalising a paper summarising the numbers of birds killed. Raptors remain the species of greatest conservation concern, with significant numbers of both Accipitriformes and Falconiformes killed, but perhaps more surprising is the indiscriminate nature of windfarm mortalities, affecting close to 100 species of birds so far at projects mainly located in the Eastern and Western Capes.
- Robin Colyn (BLSA) started working with the Fitz to better understand the factors determining the distributions of range-restricted larks in the Karoo regions of southern Africa. He will also assess display flight heights of Red Larks Certhilauda burra, a species of particular concern given the large number of wind energy projects planned in the range of this localised, vulnerable species.
- Industrial-scale solar power generation also is growing rapidly in South Africa, with little information on the impacts on biodiversity. Vonica assisted former CB MSc student Elke Visser submit a paper on the impacts on birds of South Africa’s largest photo-voltaic plant. Fortunately, Elke found very few mortalities; even accounting for a fairly high scavenger removal rate of small birds, it is unlikely that significant numbers of any bird species are being killed by the facility.
- CB MSc student Corey Jeal completed his study of a concentrated solar power (CSP) ‘trough’ facility, Bokpoort, near Groblershoop in the Northern Cape. With Vonica’s assistance, he has two manuscripts ready for submission, one reporting the impact of the facility on birds in the region, and the other on macro-invertebrates. Vonica is following up with the plant management to ensure that recommendations to reduce the risk of animals drowning in the plant’s evaporation ponds have been implemented.
- We were unable to study the impacts of CSP towers directly, but the first year of monitoring at the only facility in South Africa revealed worryingly large numbers of birds impacted by mirror collisions (mainly passerines) and solar flux damage (swifts, swallows and a few raptors).
- Jess Shaw’s paper on the impacts of powerline collisions on bustards in the Karoo was published online in Ibis.
- Additional GSM-GPS trackers were deployed on Blue Cranes in the Overberg region to track their long-term movements in collaboration with the EWT and CapeNature, with initial analyses of the data being undertaken by CB MSc student Sydney Davies.
- Vonica Perold and Samantha Ralston-Paton have summarised all reports of bird and bat mortalities for commercial windfarms undertaking post-construction monitoring in South Africa.
- Corey Jeal obtained his MSc on the impacts of a ‘trough’ concentrated solar power plant in the Northern Cape, and has two papers in preparation reporting his findings.
Endangered Wildlife Trust-Eskom Strategic Partnership; Hans Hoheisen Charitable Trust.
Prof. Peter Ryan (FIAO, UCT)
Dr Arjun Amar (FIAO, UCT)
Robin Colyn (BLSA)
Dr Andrew Jenkins (FIAO, UCT)
Dr Me gan Murgatroyd (FIAO, UCT)
Vonica Perold (FIAO, UCT)
Samantha Ralston-Paton (BLSA)
Dr Tim Reid (ANU, Canberra)
Dr Jess Shaw (Scottish Natural Heritage)
Dr Rob Simmons (FIAO, UCT)
Tanya Smith (EWT)
Students: Sydney Davies (CB MSc, UCT); Corey Jeal (CB MSc, UCT).