The future of the vulnerable Cape Vulture hangs in the balance as older design power lines continue to kill or maim birds, non-governmental organisation VulPro said this week.
In April, it recorded 23 vultures - mainly the endemic Cape Vulture - that were either killed or permanently injured on power lines around the country.
At the weekend, this number increased to 28.
VulPro founder Kerri Wolter said most of these recorded cases were in the North West and Eastern Cape.
She has raised concerns because they were used to seeing a mortality rate on power lines of around three vultures per month.
"The tragedy of this latest unacceptably high tally is that it is possible to proof powerlines to prevent these mortalities from happening," she said.
"For our team, the death by electrocution of the oldest of our captive-bred chicks, which was released last year on 8 November to help supplement the wild bird population, hit us particularly hard."
Vultures travelled long distances to look for food, water sources and breeding sites.
Vulpro said power lines were often used as a roosting point because they were elevated and allowed vultures to easily lift-off and climb thermals.
"More often than not, powerline related injuries maim birds for life, with no chance of being re-released back into the wild. Collisions usually result in broken wings and legs which may need amputation and/or pinning, whilst electrocutions nearly always result in fatality."
Eskom was aware that vultures were high-risk because of their large wingspans and heavy bodies.
They could potentially touch two live lines simultaneously, resulting in electrocution and tripping the electricity supply.
The parastatal had been recording reported incidents for many years in a national register, and also required new power lines to have a "bird-friendly" design.
Last year, a partnership between Eskom and the Endangered Wildlife Trust (EWT) resulted in the Bird Detection System (BDS).
The solar powered BDS was the first real-time system to transmit video clips or photos directly to a cellphone or data bank, with information sent straight to a cloud server.
"This device will enable us to gather information about the time of day or night these collisions occur, what the weather conditions are like at the time, and the behaviour of the bird right before colliding with a power line. This will give us far greater insight into what causes these collisions and allow us to find more effective ways to reduce them," said EWT Wildlife and Energy Programme Manager Constant Hoogstad at the time.
VulPro says many vultures die because of powerlines. (VulPro)
It was first tested in De Aar in the Northern Cape Province, where bird mortalities were high.
Eskom spokesperson Khulu Phasiwe said on Monday that they were aware of vulture mortalities and very responsive to issues raised by wildlife organisations.
"We are working together. Where we do get issues, we put mechanisms in place."
He encouraged wildlife organisations to report any issues to Eskom.
Members of the public should report wildlife deaths on electrical infrastructure to 0860 111 535.
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