Cape Town - In its heyday 22 000 years ago, the African penguin had a magnificent population of over 20 million on at least 15 large islands off the West Coast of South Africa which were home to various marine birds and penguin colonies.
Now the species is on the edge of extinction. There are approximately only 10000 breeding pairs left today after a dramatic post-1900 collapse of the African penguin population from 1.4 million.
A new study by researchers at Stellenbosch University, led by Dr Heath Beckett, argues the decline began almost 20000 years ago.
The study titled “A natural terminal Pleistocene decline of African penguin populations enhances their anthropogenic extinction risk”, found that even before the post-1900 collapse, the species suffered historic population decline due to a tenfold reduction in suitable nesting and breeding spaces which resulted from sea levels rising up to a 100m – even before anthropogenic global warming.
This gradually covered these large islands teeming with African penguins, which were then forced to “islandhop” as sea levels rose in search of suitable and safe breeding spaces (with access to sardines and anchovies), or to move on to the mainland and into conflict with humans.
Beckett said the main objective of the study was to show there had been major changes in their habitat availability over the past 22000 years.
“This could have had a massive effect on penguin populations. These populations are now experiencing additional human pressures on top of this in the form of climate change, habitat destruction and competition for food,” he said.
The researchers argue the study highlighted the potential for a reserve of resilience in African penguins that could be leveraged for its conservation and management.
Professor Guy Midgley, acting head of the Stellenbosch University School for Climate Studies and a co-author, said: “The coming risk is that future human-caused warming will exceed anything this species has seen in hundreds of thousands of years. Future species conservation efforts need to consider all this new information to allow conservation plans to be adjusted,” he said.
African penguins are climate survivors, but they are now hanging by a thread.
“African penguins wake us up to the fact that hundreds, possibly thousands, of species in the temperate and sub-Antarctic regions were climate refugees even before humans began to warm the planet, and this must inform our view of climate change risks, and how we need to respond,” Midgley said.
“It’s a total survivor and, given half a chance, they will hang on. Island hopping saved it in the past, they know how to do this,” he said.
