Flying free: Wind turbines planned for construction in the flight path of the great white pelican are likely to kill six birds per year. (Andrea Innocenti/Reda & Co/Universal Images Group/Getty Images)
BirdLife South Africa has urged the developer of a proposed wind energy facility on the West Coast to consider alternative locations to prevent vulnerable great white pelicans from colliding with its wind turbines.
In February 2012, Moyeng Energy received environmental authorisation for its proposed 35-turbine Rheboksfontein facility, which is to be built 3km west of Darling and about 15km east of Dassen Island, the only breeding site for the heavy, slope-soaring birds in the region.
The company has now proposed changes to the authorised facility, including the layout and size of the turbines, in its application for an amendment to its environmental authorisation to the department of environment, forestry and fisheries, to maximise generating capacity.
It also wants to extend the validity of its environmental authorisation, which was due to expire last month, for a further five years, “as there is uncertainty related to the commencement of round five of the renewable energy independent power producer procurement programme and resultant uncertainty of the start of construction, should the project be awarded”.
Samantha Ralston-Paton, the birds and renewable energy manager at BirdLife South Africa, said in a recent letter to Moyeng Energy’s environmental impact assessment practitioner, Environmental Resources Management (ERM), that it does not support the application as the proposed site is at an undesirable location.
“While we understand environmental authorisation for the project has been granted and renewed in the past, this does not change the fact that the site is in an ecologically important area (particularly for pelicans).”
The proposed facility, she said, is located directly within a flyway used by provisioning pelicans as they commute to and from Dassen Island.
Ralston-Paton said the environmental authorisation was based on assessments that are now inadequate by current standards and do not comply with international or local best practice.
“Between 2011-2012 (pre-construction monitoring) and eight months between 2013 and 2014 (radar study), additional data were collected. These indicated that the risk to the great white pelican, black harrier (endangered and endemic), martial eagle (endangered), African marsh harrier (vulnerable) and greater flamingo (near threatened) was more significant than initially assessed.”
Some species’ conservation statuses had also changed.
Ornithologist, Dr Andrew Jenkins, who completed the original avian impact assessment, found, in research funded by Moyeng Energy, that the project would have a considerable impact on the great white pelican, more so than initially thought.
His work used observers and radar to monitor the birds’ flight paths between Dassen Island and their core feeding ground, the Vissershok landfill, about 50km away.
Over eight months, observers recorded 407 great white pelican flocks commuting through the area, totalling 4 539 birds, with radar recording 28 783 individual pelican tracks.
However, ERM said turbine technology has significantly improved since the 2012 environmental authorisation.
“Moyeng Energy is able to increase the generation capacity or production output to 140 megawatts (from 129MW) through improvements in turbine rotor diameter (from 126m to 170m), hub height (120m to 130m) and individual turbine footprint while not increasing the project area of influence or environmental impact.
“Another benefit of improved technology is the removal of two turbines from the project layout. This will likely reduce potential project impacts, in particular related to avifaunal impacts.”
Moreover, ERM argues that the potential impact on bird species, particularly on pelicans, would now be reduced as two of the turbine locations with the highest number of “high-risk flights” had been removed from the revised development proposals.
“The predicted annual mortality of the revised layout is six great white pelicans per year, much lower than the 22 casualties per year predicted in the previous assessment.”
The updated assessment showed the Dassen Island population is declining, it said.
“The additional mortality associated with the revised project will not substantially change the current population trend, but will lead to a slight increase in the speed of the population decline.”
This is flawed, said Ralston-Paton.
“The report suggests that the proposed development would cause a slight increase in the speed of the population decline (this is not quantified) and implies that adding fatalities to an already declining population is not cause for concern.
“We cannot condone activities that will add further pressure to a declining population of a threatened species, and we suggest a precautionary approach must be adopted.”