Abstract
The demand to produce energy from renewable resources has increased alongside global energy consumption (Saidur et al. 2011). This form of energy production can help reduce carbon emissions – a long-term goal for many countries and an effective way to mitigate the effects of global climate change on biodiversity (Leung and Yang 2012). However, some renewable energy installations can have detrimental environmental impacts (Drewitt and Langston 2006, Gove et al. 2013, Loss et al. 2013, Rydell et al. 2016). Of particular concern is that threatened raptors may experience negative impacts if they collide with wind turbines and associated infrastructure (de Lucas et al. 2012a, Pagel et al. 2013). The Cape Vulture Gyps coprotheres is considered a high priority species for impact assessment and mitigation at wind farms in South Africa. This is because of the predicted risk of collisions (due to their size, behaviour and habitat use), conservation status, and overlap with proposed and operational wind farms (Retief et al. 2013, Ralston-Paton et al. 2017). T he Cape Vulture is endemic to southern Africa (Mundy et al. 1992) and has the smallest distribution of any Old-World vulture species (i.e. vultures that inhabit Europe, Asia, and Africa) (Mundy et al. 1992, Piper 2005). In 2015, the Red List status of the Cape Vulture was up-listed to Endangered because the population had decreased by 50% over three generations (Allan 2015, Ogada et al. 2015b). The species currently faces numerous threats including collisions and electrocution with electrical infrastructure, inadvertent poisoning and poaching (Allan 2015, Botha et al. 2017).
There is growing interest in developing wind energy in the Eastern Cape Province, an important area for the Cape Vulture. A number of wind farms are planned, and some are already operational in areas where interactions with Cape Vulture are possible. Cape Vulture occur regularly in at least three Renewable Energy Development Zones (areas where the large-scale development of wind energy will be promoted) (Avisense 2015), as identified in the first phase of the Strategic Environmental Assessment for wind and solar photovoltaic energy in South Africa (SEA) (CSIR 2015). To avoid adding further pressure to the species, which could contribute to irreversible population declines and local extinctions (Rushworth and Kruger 2014), guidelines are needed to help wind energy develop with the least negative effects on the species. This document provides an overview of our current understanding of the likely impact of wind turbines on the Cape Vulture and offers guidance on how the impacts should be assessed, avoided, mitigated and monitored. These guidelines focus on a project-based approach, but the importance of thorough strategic environmental assessment cannot be overemphasised. “The most effective way to detect and avoid severe environmental impacts of wind energy developments is to perform Strategic Environmental Assessments (SEAs) at large spatial scales. SEAs enable strategic planning and siting of wind energy developments in areas with least environmental and social impact whilst maintaining economic benefits” (Botha et al. 2017). However, it must be noted that BirdLife South Africa does not endorse the outcome of the first phase of the SEA due to the failure of this process to address the cumulative risk to Cape Vulture and other species. While the effects of wind farms on Cape Vultures have not been well studied, understanding the effect wind turbines have had on European and Asian vultures can provide valuable insights for their African counterparts. Wind farms have been operational in Spain for decades and several articles have been published on factors that might influence the risk of collision for Eurasian Griffon Vulture Gyps fulvus (e.g. Barrios and Rodríguez 2004, Carrete et al. 2012, de Lucas et al. 2012a). This species is similar to the Cape Vulture in regard to its flight patterns, behaviour, vision morphology, and colonial cliff breeding strategies (Mundy et al. 1992, Carrete et al. 2012, Martin et al. 2012). These guidelines draw on lessons from these examples, but it is important to note that there are differences in vulture population size, land use, food supply, and human population densities that must be taken into account. As our knowledge grows, the recommendations contained in these guidelines may be amended to reflect our improved understanding of how vultures can flourish alongside increased generation of renewable energy. These guidelines expand on the recommendations in the BirdLife South Africa/Endangered Wildlife Trust Best Practice Guidelines for Birds and Wind Energy (Best Practice Guidelines) (Jenkins et al. 2015). These documents should therefore be read together.