A drastic decline in African penguin populations at the St. Croix Island colony in Algoa Bay is ringing alarm bells about the impact of human activity and climate change on the birds.
African penguins are listed as endangered by the International Union for Conservation of Nature.
Professor Lorien Pichegru of Nelson Mandela University’s Coastal and Marine Research Institute has been researching the impacts of various anthropogenic threats on African penguins in Algoa Bay for 15 years. She said the colony on Dassen Island, once the largest colony of African penguins in the world, collapsed by 90% in the mid-2000s, making the colony on Sainte-Croix Island in the Algoa Bay the second largest colony in the world.
“Now this one is collapsing too,” she said.
Pichegru said the reason for the decline in penguins is due to a lack of prey and sustained high fishing pressure, particularly on the west coast, as the fishing industry operated mainly from Cape Town and the bay of Saint Helena.
This and additional pressures on the colony of St. Croix contributed to its recent collapse in Algoa Bay.
“I carried out a population census on the island of St. Croix a few months ago on behalf of the Department of Forestry, Fisheries and the Environment, with the assistance of South African National Parks We have counted over 1,000 breeding pairs, which is about 2,500 penguins, counting those that are not breeding,” she said.
Pichegru said that corresponds to a 90% decrease from 10 years ago, while the penguin colony on Bird Island has halved over the same period.
“Penguins barely move once they start breeding in a colony. These penguins are dead. I counted a large number of dead adults on the beach along the Alexandria dune field in part of long-term monitoring research that I am conducting with Bayworld colleague Dr. Greg Hofmeyr As African penguins across South Africa decline at an alarming rate, so do gannets and Cape cormorants, all three endangered, all three dependent on small pelagic fish, sardines and anchovies, as prey.
“The number of Cape Gannets counted dead along the Alexandria dune field in Algoa Bay has also increased drastically,” Pichegru said.
She said stocks of small pelagics have recently declined in part due to climate change.
“We cannot change the climate to improve conditions for fish, to increase food availability for seabirds. One can, however, stop fishing around their colonies. My research has repeatedly proven over the years the benefits of sardine fishing exclusion zones around penguin colonies for nesting birds.
“It was confirmed in the West Coast settlements by colleagues of mine. However, no effective closure has been implemented to date for two years, despite the minister’s promises. These are urgently needed,” she said.
Pichegru said Île Sainte-Croix is particularly vulnerable due to its location downwind of the bay, which limits the size of penguin feeding habitat.
“Changes in prey availability are felt much more quickly by breeding penguins. In addition, the proximity of two industrial ports increases noise pollution levels in the penguins’ feeding habitat, and bunkering activities greatly increase the risk of oil spills, as shown by the four oil spills that have occurred in the bay since 2016, since the start of ship-to-ship bunkering in the bay,” said Pichegru.
She said noise pollution is something scientists and the community have only recently begun to recognize globally, and her latest research shows that noise levels in the bay have doubled since 2016, due an increase in maritime traffic in the bay since the start of bunkering, affecting many levels of the ecosystems.
“Fish, invertebrates, birds and marine mammals use sound to communicate, find food, find mates, locate predators, etc. Penguins are canaries in the coal mine, revealing the underlying problems sailors that we cannot see. Noise mitigation measures will need to be put in place and discussions with the South African Maritime Safety Authority are ongoing,” she said.
According to the Southern African Foundation for the Conservation of Coastal Birds Eastern Cape and BirdLife South Africa websites, in 1910 an estimated 1.4 million African penguins lived on Dassen Island alone. In the late 1970s, the estimated number was 222,000 birds. By the late 1980s this number had dropped to 194,000 birds and by the early 1990s to 179,000 birds. Two years ago, that number had dropped to around 47,000 birds.
Gary Koekemoer, president of the Algoa Bay branch of the Wildlife and Environment Society of South Africa, said the tragic irony is that at some point the population of St. Croix was increasing. In the mid 1980s St Croix was home to 44,781 penguins and by the early 1990s this number had risen to 62,330 penguins.
“Pelagic fish stocks in the region have been decimated by overfishing. Bunkering is also essential. The only anchorage is adjacent to islands and Marine Protected Areas (MPAs), so underwater noise and regular oil spills have a huge impact on the penguins. Climate change has an additional impact as sea temperatures change, reefs die, weather patterns change and as a result food chains collapse,” Koekemoer said.
He said pelagic fishing and bunkering should be stopped.
“St Croix should be isolated from humans and these [measures] will undoubtedly contribute to restoring one of the main indicator species of our bay. Is it doable? Some say absolutely, we’d be crazy not to. Others say the opposite, we are crazy to think we can stop all economic activity based on the sea and we shouldn’t because it puts food on the tables.
“Our Constitution and our environmental laws enshrine the principle of sustainable development, the idea that all development (i.e. human activity) must balance economic, social and environmental factors,” he said. .
He said there was a need for proper environmental risk assessment and reduced fishing near the settlement.
“Move the moorings to a new location that creates a buffer zone and move the shipping lanes. Strictly control existing bunker requirements. Pressure decision makers and their institutions to let go and do the things already agreed upon,” he said.
Koekemoer said they need to get bunker operations and businesses that profit from using the bay to pay their taxes, like all other businesses, to fund proactive conservation and restoration initiatives.
Enviro-Quest chief executive Ronelle Friend said the drastic drop in penguin numbers on the island has occurred over the past five years, coinciding with the timing of ship-to-ship (STS) bunkering. in the Bay.
“STS bunkering began at the end of 2016 in the mooring areas of the port of Coega. Anchorage area 2 is just off St. Croix Island and flush with the boundary of the Addo Marine Protected Area. The distance from where Umnenga II, the mothership, is anchored to St. Croix Island is 2 km,” she said.
Pichegru adds: “As penguins are indicators of the ecosystem, their protection is likely to benefit other species in their habitat. Communication is the key to conservation and dialogues between conservationists and industries are crucial to moving together towards a sustainable future. DM/OBP