This project mitigates the impacts of power generation and transmission infrastructure on birds. The focus is on both collision impacts associated with powerlines, which mainly affect large, open-country birds such as bustards and cranes, and the impacts of renewable energy technologies, particularly wind, which disproportionately affects raptors.

Renewable power generation has much less broad-scale environmental impact than the coal-fired power stations on which South Africa relies for most of its electricity, 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. The programme is run in collaboration with BirdLife South Africa’s Birds and Renewable Energy programme, the Endangered Wildlife Trust (EWT) and HawkWatch International (HWI).

Activities in 2025

  • PhD student Marc Travers made impressive progress towards completing his PhD on powerline collisions by birds on Kauai, the westernmost of the main Hawaiian islands. The main focus on his research has been assessing the extent of collision mortality in two threatened seabirds, Hawaiian Petrels Pterodroma sandwichensis and Newell’s Shearwaters Puffinus newelli, but he also assessed the risk to other species, including several threatened waterbirds. Unlike most powerline collision risk studies, his main approach was to directly observe the outcome of bird flights at powerlines, which provides a very different perspective to periodic surveys for collision victims beneath powerlines. His findings, based on almost 13 000 hours of observations by day and night, indicate the importance of light levels on collision risk, even for species not typically considered to be active at night. He also confirmed that traditional surveys for collision victims vastly underestimated bird mortality, especially in the dense tropical vegetation found on Kauai. Marc will submit his thesis in early 2026.
  • Robin Colyn completed another chapter for his PhD on display flight heights of various threatened southern African larks and pipits to assess their vulnerability to collision mortality with wind turbines.
  • PhD student Merlyn Nkomo continued her PhD research into the potential impacts of wind farms on Jackal Buzzards Buteo rufofuscus. She made progress with her second chapter on population models and is nearing its completion. She has begun her third chapter on the variation in home range size in Jackal Buzzards and the factors affecting it.
  • Merlyn travelled to Montpellier, France, on a scholarship to present her work at the Conference on Wind energy and Wildlife Impacts (CWW). She was later invited to present her work at the Oppenheimer Research Conference.
  • Dr Megan Murgatroyd and A/Prof. Arjun Amar continued their research on Black Harriers Circus maurus, with the aim of providing tools to reduce the impact of wind energy developments on this vulnerable species. Working with their own tracking data, combined with tracking data kindly provided by the Overberg Renosterveld Trust and Birds and Bats Unlimited, they undertook two key projects. i) Conservation Biology MSc student Sebastian Acevedo built a predictive space use model of breeding harriers to help wind farm developers to place turbines in less vulnerable locations. Sebastian will submit his project in early 2026. ii) Michelle Vrettos, using the same tracking data, built a dynamic risk model that aims to identify the conditions (month, time of day, weather conditions) when harriers are most likely to fly at risk height; this model can be used to help wind energy operators pre-emptively shut down their turbines to reduce risk.
  • Arjun and Megan remain involved in several projects in which wind farms are undertaking patterning of wind turbine blades to test whether this mitigation method can reduce the number of birds killed by wind turbines. The team has been trapping and tracking Verreaux’s Eagles Aquila verreauxii at a wind farm in the Karoo, where blade patterning on existing turbines will occur in 2026, to explore whether the species avoids areas near wind turbines once a blade is patterned. The team has also been working with developers at a site that will become operational in 2026, at which a third of the turbines will be patterned and the remaining ones left unpainted as controls to explore differences in fatality rates between the two groups of turbines.
  • Honours student Connor Barr, supervised by Arjun and A/Prof. Robert Thomson, completed a dissertation that aimed to estimate the overall population size of six raptor species vulnerable to wind energy impacts. These estimates will feed into future cumulative impact models, making the models much more reliable.

Highlights:

  • Former PhD student Dr Christie Craig (EWT) had the first paper from her thesis, reporting changes in the breeding success of different regional populations of Blue Cranes Grus paradisea, accepted for publication in Ostrich. She suggests that decreased breeding success might at least partially account for the recent decrease in crane numbers in the Overberg region of the Western Cape.
  • John Pallett had his estimates of large bird collision mortality along powerlines in southern Namibia, based on data collected in 2012/13, accepted for publication in Ostrich.
  • Merlyn Nkomo was awarded a fellowship with the Mawazo Institute, which supports African women in research, and she also received a scholarship to present a paper at The Conference on Wind Energy and Wildlife Impacts (CWW) in France. She won the Best Presentation award at the Oppenheimer Research Conference.
  • Megan Murgatroyd and Arjun Amar published a paper titled ‘Applied solutions to balance conservation need with practical applications: a case study with eagles’ movement models and wind energy development’ in Ecology & Evolution, which refined the output of our VERA model to reduce uncertainty about its application by developers.
  • Megan Murgatroyd co-authored a paper called ‘Impacts of onshore wind energy production on biodiversity’ that was published in Nature Reviews.

Key co-supporters
HawkWatch International; Endangered Wildlife Trust – Eskom Strategic Partnership; The Bateleurs; BirdLife South Africa; BTE Renewables; Hans Hoheisen Charitable Trust; Leiden Conservation Fund; Dave Myers; The ABAX Foundation; The Shannon Elizabeth Foundation; Oppenheimer Memorial Trust (OMT)

Research team 2025
Emer. Prof. Peter Ryan (FIAO, UCT)
A/Prof. Arjun Amar (FIAO, UCT)
Dr Megan Murgatroyd (HawkWatch International / FIAO, UCT)
A/Prof. Robert Thomson (FIAO, UCT)
Dr Chris Vennum (USGS)
Dr Rob Simmons (Birds & Bats Unlimited / FIAO, UCT)
Dr Odette Curtis (Overberg Renosterveld Conservation Trust)
Dr Alan Lee (BLSA / FIAO, UCT)
Michelle Vrettos (FIAO, UCT)

Students: Robin Colyn (PhD, UCT), Merlyn Nkomo (PhD, UCT), Marc Travers (PhD, UCT), Sebastian Acevedo (CB MSc, UCT), Connor Barr (Hons, UCT)