Black Harrier Research

Protecting a species through research and conservation

Black Harriers and other Red Data species in the proposed Boulder Wind Farm: a re-assessment, January 2020

Dr R.E. Simmons Black Harrier Research Group, FitzPatrick Institute, UCT

Dr R E Simmons, Honorary Researcher, Percy FitzPatrick Institute, University of Cape Town, Rondebosh, 7700, Cape Town, South Africa [email protected] +27 (0)82 780 0133 RATIONALE The proposed Boulders Wind Farm in the Cape Columbine area, east of Paternoster, has attracted public criticism from conservation groups in the area due to its proximity to various nationally important biodiversity areas, and visual and archaeological concerns. I was asked by the concerned groups, as a specialist on raptors, and particularly Endangered Black Harrier Circus maurus, to re-assess the Red Data species in the area and review the avian EIA Report prepared for the Boulders wind farm site. The Cape Columbine area has recently been identified as a nationally important core area for breeding harriers, so I spent three days on site in late January 2020 to prepare a specialist report as part of the Appeal Process. I also spoke to local birders and met with the conservationists. This is a report of my findings. BACKGROUND The proposed Boulders site is a Wind Farm comprising 45 turbines of hub height 120-m, placed on 10 farm portions surrounding the existing and operational West Coast 1 Wind Farm (WC1WF). The West Coast 1 site was subject to an avian assessment, mitigation measures, and has at least one year of carcass data available. This allows a direct assessment of the likely impacts to the avifauna of the area if the neighbouring Boulders site goes ahead. Scoping and full EIA studies have been undertaken by Bioinsight from 2014-2015, followed by a brief site visit in October 2017 to determine if the receiving environment had changed. The Boulders Wind Farm was given Environmental Authorization late in 2019 (4 years after the study) despite several recommendations from Visual, and Archaeological specialists being ignored. As an avian research biologist, specialising in threatened raptors and Black Harriers I have re-appraised the avian specialist report and undertaken a short field trip to determine possible impacts to the avifauna of the area. I have no vested interest in the site other than protection of Black Harriers and other Red Data species that may be unnecessarily impacted by the Boulders WEF.

Photo 1: Black Harriers are common and resident in the coastal areas of the Cape Columbine area. (RE Simmons) SUMMARY The Boulders Wind Energy Facility (WEF) is proposed for high ground south of St Helena Bay and east of the archaeological site at Kasteelberg (Sadr et al. 2017). It covers ~27-km2 of farmland and some natural wetland areas in the Fynbos biome. A Scoping and full EIA report on the avifauna was completed in 2015, 5 years ago (BioInsight 2018) and that was reviewed by Jenkins (2019). The BioInsight report found no fatal flaws from an avian point of view, and ranked the avian risks as medium. This was challenged by Jenkins (2019) who suggested that their avian report was barely adequate, provided little in the way of raw data (passage pates, flight heights, probability of species occurring and field effort) on which to judge their conclusion. The authors also suggested erroneously that Lesser Kestrels (a European migrant) might breed at the site. Jenkins (2019) disagreed that the site should be given clearance based on numerous false claims. Also, worryingly, the meat of the radar study was not presented, despite annual estimates of hundreds of thousands of birds using the aerial flyway over the neighbouring wind farm (Millikan 2013). The BioInsight report appears to have under-estimated the likely fatalities of Red Data birds at the Boulders WEF. A simple simulation of likely avian fatalities, based on the known kill-rate of Red Data raptors at the operational and neighbouring West Coast 1 Wind Farm, accounting for (i) scavenging rates; and (ii) taller turbines at Boulders (120-m vs 80-m) predicts that: 132 raptors (of which 18 are Red Data species) are likely to be killed annually at the Boulders WEF. This is likely to include the Endangered Black Harriers given that:

❖ recent modelling found the Cape Columbine area is one of the most suitable habitats for breeding Black Harriers in South Africa (Colyn et al. in prep.). ❖ Black Harriers have also been recorded on the proposed Boulders site and are resident, and breed, in the surrounding coastal areas. ❖ The Cape Columbine area is one of few areas in South Africa where Black Harrier records are increasing, based on comparisons between national bird atlas schemes. ❖ The radar study of nocturnal bird movements over WC1WF in 2013 indicates 256 000 birds fly over the site annually of which 16% (41 000) flew in the blade-swept zone. Some of these would be Red Data Blue Cranes and Flamingos. A 3-day visit in January 2020, confirmed that Black Harriers, the 6th most collision-prone species in South Africa, were present in the Groot Paternoster reserve about 5-km north-west of the site. The presence of these Endangered birds, and suitable harrier nesting habitat in the centre of the Boulders WEF, suggests that the site is likely to be a danger to the Black Harrier population, and further investigation is essential. Population modelling of Black Harriers at Wind Farms in the Eastern Cape indicate that even at low- level mortality rates of one adult, or one juvenile, killed at five Wind Farms every two years, the global Black Harrier population will decline. The impact of the presence up to 220 Red Data Blue Cranes may also have been under-estimated by the BioInsight report, since they are the 11th most collision-prone species in South Africa, and two to three fatalities are expected annually on the power lines required by the WEF. I conclude that this Wind Farm poses a significant threat to Black Harriers and other avian Red Data species in the area, and that avifaunal impacts need to be independently reassessed and the farm re- sited.

QUALIFICATIONS OF AUTHOR Dr Rob Simmons is an ornithologist with 35 years’ experience in avian research and impact assessment work. He has undertaken specialist avian impact assessment since 2010 and, as a consultant, has undertaken 70 projects and assessments over 23 habitats in Angola, Kenya, Lesotho, Namibia and South Africa. His long-term avian research has been focussed on threatened species: Black Harriers (18 years); population surveys of flamingos in southern Africa, and population surveys of endemic species (across an aridity gradient over 3 years); and desert-wide surveys of threatened terns. In his academic capacity he has published over 110 peer-reviewed papers, two books and contributed to nine others. As an Honourary Research Associate with the FitzPatrick Institute Centre of Excellence at UCT, he also works on the effects of climate change on birds, improving vantage point observations at Wind Farms with statistical models, as well as the impact of domestic cats on biodiversity with MSc and PhD students at the FitzPatrick Institute, UCT. A full academic CV is available at www.fitzpatrick.uct.ac.za/fitz/staff/research/simmons and his consultancy experience is available at www.birds-and-bats-unlimited.com/birds RESULTS The Boulders Wind Farm has become a controversial topic among residents of the Paternoster and St Helena Bay area because of its visual impact, and the likely impact on this area of outstanding natural beauty and biodiversity. Here we assess the avian impacts. EXPECTED RAPTOR MORTALITIES at the BOULDERS WIND FARM It is important, but rarely possible, to understand the direct impacts of a proposed Wind Farm. It is nevertheless critical to understand what fatalities may occur and which species are likely to be affected. The ultimate measure of the potential impact of a proposed Wind Farm is to compare it with a neighbouring operational Wind Farm of the same capacity, in similar habitat. This we can do using results from the operational West Coast One Wind Farm (WC1WF) adjacent to the proposed Boulders Wind Farm (Figure 1). This has been surveyed for carcasses by Jenkins et al. (2017) who found, in 14 months’ post-construction monitoring, 54 bird carcasses. Among them were 31 (57%) birds of prey carcasses. These included an Endangered Martial Eagle (n=1), Vulnerable Lanner Falcons (n=3) and Least Concern Jackal Buzzards (n=17). These represent a high 2.2 raptor fatalities per month. Four of the 31 raptors (13%) were Red Data raptors. These are unadjusted fatality rates, and they arose despite mitigations, and despite drought conditions over the Western Cape. If we account for scavenger removal rates (60% in South Africa) that typically occurs within the first few days (Shaw et al. 2015), we can calculate that a minimum of 90 carcasses occurred at WC1WF before scavenging. This assumes all were located which is rarely true, so what follows are minimum estimates.

Assuming the same proportion of raptors (57%) within those 90 carcasses over 14 months, we can make the following deductions for avian fatalities likely at the same sized Boulders WEF in a dry year:

• A minimum of 77 birds will be killed per year at the Boulders Wind Farm; • About 57% (44) of these will be raptors; • About 13% (6) of these will be Red Data raptors per year. Figure 1: The extent of the Boulders WEF (grey polygon) and records of Red Data raptors and cranes present on the site over the last 3-4 years. Endangered Black Harriers (= red balloons) have been recorded foraging on the Boulders site and are particularly common in the most coastal areas where indigenous vegetation remains to the north and the west. A satellite-tracked harrier set up a non-breeding roost 4.5-km west of the proposed WEF in 2009-2010 (= orange polygon “core Black Harrier Roost [Lockie]”) and foraged across the Wind Farm. Suitable breeding habitat was also identified in the eastern arm of the proposed WEF (= green polygon). Over 200 Blue Cranes (= blue balloons) are known to frequent the area, and at least 100 of those have been recorded inside the proposed Boulders WEF. A Vulnerable Secretarybird nest (= white balloon) was discovered in 2015 inside the Boulders site by Marlei Martins. These are minimum fatality estimates for the Boulders WEF because: (i) not all carcasses are found (observer bias) and accounted for above; (ii) dry years typically support lower species diversity and harriers than wetter years in southern Africa (Seymour et al. 2015, Garcia-Heras et al. 2016); (iii) the turbines (120-m) planned for Boulders WEF are larger than the operational turbines at WC1WF (80-m). Taller turbines kill disproportionately more birds than shorter ones (Loss et al. 2013, and Figure 2). We have modelled the USA data, taken from 54 Wind Farms with suitable data, and added the existing South African data (Ralston et al. 2015) to it. (iv) Turbines of 120-m hub height are predicted to kill three-fold more birds (6.8 vs 22.0 birds/turbine/year) than 80-m turbines. Thus, the number of raptors likely to be killed by taller turbines at the Boulders site will exceed the 44 raptors and six Red Data raptors by an estimated three-fold – with likely annual fatality rates at about 132 raptors per year, of which 18 Red Data raptors are forecast to be killed. The effect of tall turbine on avian fatalities does not appear to have been taken into account in the Bioinsight report, even though they were aware of the Loss et al. (2013) paper.

Figure 2: Modelled results of avian fatalities in relation to hub height for turbines above 80-m (the hub height of the West Coast 1 WEF). Data taken from Loss et al. (2013) and modelled with 95% confidence limits. The jagged lines are the 95% boot-strapping confidence limits to determine if the South African data (red dots) fall within the limits of the modelled data – which they do. (Dr B Erni, Stats Dept Uct). Figure 3: By incorporating the South African data (n = 8 fatality points) into the USA data we can estimate that for 80-m turbines an average of 6.8 avian fatalities are predicted per turbine per year. For 120-m-high turbines (red line) an average of 22 fatalities/turbine/year are predicted – 3 x higher than the 80 m turbines. These figures are used to predict how many fatalities can be expected at the Boulders Wind Farm with taller turbines. (B Erni and F Cervantes Stats Dept, UCT). OCCURRENCE of ENDANGERED BLACK HARRIERS in the BOULDERS SITE Black Harriers are one of South Africa’s rarest birds with an estimated 1 000 mature individuals in the global population (Curtis et al. 2004, Simmons et al. 2005, Taylor et al. 2015). It has recently been found to be highly susceptible to impacts with turbines, especially during the breeding season when birds soar to heights dangerously compatible with the blade swept areas of turbines (Simmons and Martins 2018). Based on an 18-year programme of research and satellite tracking (Garcia-Heras et al. 2019) suitable breeding areas were modelled for this Endangered species (Colyn et al. in prep.). We identified about seven core areas in South Africa where habitat was highly suitable for breeding (Simmons et al. 2020). The Cape Columbine area is one of those areas (Figure 4). As such, it is critical to conserve it and to reduce impacts to Black Harriers there. This indeed is one of the recommendations of the Black Harrier Guidelines aimed at reducing Wind Farm impacts to Black Harriers (Simmons et al. 2020). Whilst Black Harriers were mentioned in the Bioinsight (2018) report as a species with “an unfavourable conservation status” (it is Endangered) the extent of the birds’ occurrence was not gauged, despite SABAP 2 data being available for this exercise (Figure 5). This comparison of SABAP 1 atlas data with SABAP data shows that the Cape Columbine area is one of the few regions where harrier sightings have either increased as gauged by Reporting Rate (presence per 100 atlas cards), or occurrence has increased (recorded in SABAP2 but no records in the SABAP1 atlas period (Figure 5).

Figure 4: Black Harrier breeding suitability model (Colyn et al. in prep.) showing the most suitable core areas for breeding in the Western Cape. All blue and green areas are high-use areas from ~5% suitability (green) to the highest category above 40% suitability (blue).

Figure 5: National Bird atlas data for the Black Harrier from the SABAP1 vs SABAP2 schemes of the Animal Demography Unit, UCT. Globally, Black Harriers have decreased between these two schemes about 21% over ~20 years, yet the Cape Columbine area (circled) is one the few places where increases in reporting rates (green squares) or new occurrence (blue squares) have been detected. That is, harrier sightings have increased over 20 years and the area is increasing in importance as a core Black Harrier stronghold.

SABAP1 & SABAP2 data, species only present SABAP1

SABAP1 & SABAP2 data (Rep rate reduced in SABAP2) Decrease

SABAP1 & SABAP2 data (Rep rate increased SABAP2)

SABAP1 & SABAP2 data, (species only present SABAP2) Increase

No breeding areas were found on the proposed Boulders Wind Farm (this survey was outside the breeding season), but harriers forage through the natural remaining habitats. This was confirmed by two sets of data collected by M Martins as a specialist observer in 2015 (Figure 6), and also confirmed by satellite tracking data from 2009-2010. The first female satellite-tracked bird (Lockie) in the long-term Black Harrier Research Programme at UCT flew from the Niewouldtville area to Cape Columbine in December 2009 and stayed there from 7 December 2009 to 25 January 2010, a total of 45 days (Garcia-Heras et al. 2019). She crossed the proposed Boulders site at least twice during this period (Figure 6) and set up a temporary roost just south of Paternoster. Breeding is also likely, but unconfirmed, in several areas surrounding the Boulders site: (i) at Groot Paternoster Nature Reserve (2 adults in three days in January 2020), and two young birds in December 2019 (P Pickford pers. obs.). (ii) An adult pair and a young bird were also photographed (Photo 2) over Britannia Heights in August 2017 (J and A Todd pers. obs.) suggesting breeding took place less than 5-km from the northern boundary of the Boulders Wind Farm.

Photo 2: Black Harriers are common and resident in the coastal areas of the Cape Columbine area. These birds were photographed in August 2017 south of Britannia Heights less than 5-km from the Boulders WEF and a juvenile bird was in attendance (J Todd).

Photo 3: Possible Black Harriers breeding habitat discovered at S32°49'15" E 18° 0'26" on the Boulders/WC1WF border (RE Simmons). The habitat comprises a mix of Sarcocornia and Juncus, both favoured nesting vegetation types for Black Harriers. Surveys in July 2020, when birds return to the Western Cape, will determine if this habitat is used or not. What effect would wind farm harrier deaths have on the Black Harrier population? Population viability modelling of Black Harriers for another wind farm project in the Eastern Cape calculated what the effect of one adult or one juvenile killed every second year would be on the population (F Cervantes unpubl data). The results were quite dramatic for this Endangered species: If just 5 wind farms were to kill one adult harrier every second year the Black Harrier population would decline fast (Figure 7). The decline would amount to 19% in 50 years. Similar modelling at a higher rate of 3 adults killed every second year by just five wind farms in South Africa would have dramatic effects on the harrier population. The Black Harrier population would then collapse in about 125 years. That model predicts an average decline of 30% in 30 years or 50% in 50 years (F Cervantes unpubl data). I give these results to show that any Black Harrier killed at wind farms in South Africa will affect the global population so any proposed wind farm that may kill Black Harriers must be reconsidered.

Figure 7: If five wind farms were to each kill one adult harrier every second year, the Black Harrier population will decline rapidly. The model predicts an average decline of 11% in 30 years (19% in 50 years).

To summarise the Black Harrier findings for the Cape Columbine area:

• National Bird Atlas data (SABAP 1 vs SABAP 2) indicates that Cape Columbine is one the few areas in South Africa where Black Harrier sightings have increased (Figure 5); • Modelling of habitat suitability indicates that Cape Columbine falls within the highest habitat suitability category, one of just seven such areas in South Africa (Figure 4); • Satellite-tracking data indicates that some harriers use this area extensively prior to migration to Lesotho (Figure 6); • Movements across the Boulders site, and probable breeding records of harriers in the coastal area surrounding the WEF, were revealed from the records of M Martins in 2015, A and J Todd in 2017, P and B Pickford in 2019, and in this site visit in January 2020 (Figure 6); • Potential harrier breeding habitat was discovered on the border of the Boulders WEF and the WC1WF in January 2020 and a 3-5-km buffer would be required (Simmons et al. 2020) around it if Black Harriers are found to be breeding here in follow up visits in July 2020. • Modelling of wind farm deaths as low as 1 adult every second year at just five WEFs is sufficient to push the global Black Harrier population into steep decline and at higher rates will cause it to collapse in just over 100 years. These findings illustrate that the Cape Columbine area, with the Boulders WEF in the centre, is one of the most sensitive sites for Black Harriers in South Africa and should not be developed to safeguard the species from further impacts and long-term population decline. OCCURRENCE of NEAR THREATENED BLUE CRANES in the BOULDERS SITE The presence of Near Threatened Blue Cranes was reported from the Boulders WEF site, by Bioinsight (2018), but no indication of numbers was provided. These are categorised as the 11th most collision- prone species at South African Wind Farms (Ralston-Paton et al. 2015). Blue Cranes occur year-round on the Boulders site but are especially numerous after harvesting of cereal crops (C de Kock pers comm.). Figure 1 indicates the position of the regular and major accumulations recorded over the last three years in and around the proposed WEF site. The total numbers are estimated to be 220 birds, with regular breeding occurring on the site (C de Kock unpubl data). This was confirmed in the January 2020 site visit, when two adults with two chicks recorded there. While Blue Cranes are rarely victims of turbine impacts (Ralston-Paton et al. 2015), they are one of the most frequent victims of power line collisions (Shaw et al. 2010). The number of collisions, with scavenging biases accounted for, is 0.31 cranes/km of line per year in the Overberg and at these rates 12% of the total population of the Overberg’s crane population is killed annually. If we apply these rates to the five proposed alternative routings for the 132-kV lines from the Boulders WEF (6.2-km to 9.4-km) then we can estimate that:

• For the shortest route (6.2-km x 0.31 cranes/km) = 2 cranes/year may be killed annually. • For the longest route (9.4-km x 0.31 cranes/km) = 3 cranes/year may be killed annually. Whilst the impact of power lines was mentioned in the BioInsight report, there are still no known effective mitigations for bustards or cranes as they do not see bird diverters. Thus, the mitigations would have to be innovative and spelled out clearly. More importantly, the radar studies indicated that of an estimated 256 000 birds per year, 16% (41 000) flew in the blade swept zones of the operation WC1 Wind Farm and some of these are likely to be Red Data cranes or flamingos (Millikan 2013). This potential impact was not mentioned by BioInsight (2018) and this would require major mitigations or a re-siting of the proposed Wind Farm to avoid major fatality rates.

Photo 4: Blue Cranes on the proposed Boulders site. Over 100 birds occur on the site shortly after harvesting. Figure 6: Records of Black Harriers in and surrounding the Boulders WEF site (= grey polygon). A satellite-tracked female (Lockie) flew to this area from Niewoudtville in December 2009 and stayed 45 days before heading to Lesotho. Her core area south of Paternoster is indicated (= bright orange polygon), but she also foraged across the Wind Farm as judged by the Maximum Convex Polygon (= brown polygon). Other records (= red balloons) are Black Harrier records from 2015 (on the WEF site), or from 2019 and 2020 for resident pairs or individuals and juveniles at Groot Paternoster Nature Reserve, and Britannia Heights (far north). Possible breeding habitat within the Wind Farm (= green polygon) was also found during the January 2020 site visit.

To conclude, the Boulders Wind Farm is sited in an area of outstanding biodiversity and a major stronghold of the Endangered Black Harrier. Several measures indicate that the area is growing in importance for this species, and they may indeed breed on the proposed wind farm site. The Bioinsight (2018) report appears to have overlooked the threats to this species and the sheer numbers of at least 41 000 birds passing overhead at night within the blade swept zone of the adjacent Wind Farm (Millikan 2013). Independently of radar studies we have calculated that at least 132 raptors, of which 18 are Red Data species, are predicted to be killed annually at the Boulders WEF, based on fatality rates at WC1WF and the risks of taller turbines. The Biosight report was also completed in 2015 and thus the area should be re-appraised given that 5 years have passed since the study, and 3 years have passed since the walk-through in 2017. All lines of evidence strongly suggests that the Environmental Authorisation for the Boulders WEF must be over- turned and the Wind Farm re-sited in a less sensitive area, away from the suite of threatened species (Blue Cranes, Secretarybirds and flamingos) but especially the Endangered Black Harrier,. ACKNOWLEDGEMENTS Dr Muller and Christine Coetzee of Planet Capital and photographers Peter and Beverley Pickford are thanked for their hospitality and generosity, and to them and Anne and John Todd, and Colin de Kock for harrier and Blue Crane data and photographs. Marlei Martins added valuable harrier and Secretarybird records from the Boulders site and edited this report. Drs Francesco Cervantes Peralta and Birgit Erni kindly assisted with statistical modelling expertise. REFERENCES

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