Penguins on the precipice: Survival in the ‘noisiest bay in the world’

Bunkering in South Africa’s Algoa Bay has dramatically cut the population of the former world’s largest colony.

The first time I visited St Croix island, in 2017, it was home to about 6,000 breeding pairs of African penguins – 35 percent of the global population of this endangered species.

On a blissful September morning, we sped across Algoa Bay on South Africa’s east coast, past a grimy cargo ship and the bulging meringue that is the Nelson Mandela Bay football stadium, before stopping alongside St Croix. The boat rocked from side to side as waves broke against the tiny, jagged outcrop that has wrecked many a ship over the centuries.

To the human eye, the rocky, sun-baked pinprick seemed a pretty inhospitable place but birds clearly saw things differently. A waddling throng of knee-high penguins huddled above the high-water mark while, behind them, a lone gull perched on a replica of the cross erected by the Portuguese explorer Bartolomeu Dias in 1488.

As we rounded the island, the huge Ngqura Port and its floating fuel stations came into view. In 2017, the practice of ship-to-ship bunkering (refuelling at sea) had only been going for one year. Back then, the biggest concern about bunkering was that it would result in oil spills. While there have been four spills – in 2016, 2019, 2021 and 2022 – some of which killed penguins, the noise caused by the bunkering activities is likely even more devastating to the birds.

“In a bid to avoid the noise, the penguins swim further, to less productive feeding grounds. This means they can’t build up enough reserves to survive the moult, when they have to fast for three weeks,” explains Lorien Pichegru, an adjunct professor at Nelson Mandela University, who has been studying the penguins on St Croix since 2008.