Bird numbers plummet due to shipping noise pollution
An endangered penguin species is facing another hurdle.
THE already endangered African penguin is being driven away from its natural habitat off the east coast of South Africa due to noise from ship refuelling, a scientific study has found.
The number of African penguins on St Croix island in Algoa Bay, once the world's largest breeding colony of the birds, has plummeted since South Africa started to allow ships in the area to refuel at sea, a process known as bunkering, six years ago, the study found.
Situated in a busy shipping lane along South Africa's east coast, Algoa Bay is rich in marine and bird life where southern right whales roam in its sheltered waters.
``We found the noise levels, which were already high, to have doubled'' since bunkering began, Lorien Pichegru, acting director of the Coastal and Marine Research Institute at Nelson
Mandela University, which led the study, said.
Elevated noise levels affect marine animals' ability to find and corral prey, communicate or navigate properly, scientists have previously found.
``This year we are at 1200 breeding pairs at St Croix from 8500 pairs in 2016, an almost 85% decrease since bunkering started in South Africa,'' Pichegru said. ``I was counting the dead birds every month on the beach of the bay.''
The study, published in the peerreviewed Science of the Total Environment journal, is the first to explore the impact of maritime traffic noise pollution on a seabird, and the consequence of offshore bunkering activities on underwater noise levels, researchers said.
Pichegru said penguins in the St Croix islands were already struggling to breed due to a variety of challenges, including industrial fishing of scarce prey.
``Bunkering did not kill all the penguins, it was just the thing that made the whole ecology tip over and then the penguins couldn't cope with that,'' she said. — Reuters