Closing the waters around Robben Island in South Africa to fishing for a three-year trial period helped increase the survival of endangered African penguin chicks by 18 percent, researchers at the University of Exeter in the UK report in a new study.
The research team published their results in the latest edition of the Royal Society Journal Biology Letters, and the findings indicate that prohibiting fishing activities, even in small areas, can drastically improve the survival chances of threatened creatures.
“One of the major challenges of conserving a mobile species like the African penguin,” said Dr. Richard Sherley, a research fellow at the university, “is that once they leave a protected area they are subject to outside pressures and dangers, including poor prey availability.”
“Our study shows that small no-take zones can aid the survival of African penguin chicks, but ultimately commercial fishing controls must be combined with other management action if we are to reverse the dramatic decline of this charismatic species,” he added.
Benefits of small-scale fishing bans
The African penguin population is currently in a freefall, with adult survival rates plummeting over the last decade – and even though the Robben Island ban on commercial fishing improved chick survival rates, overall prospects of the species remain dim over the long haul.
African penguins feed on anchovies and sardines, but fishing of those species near Cape Town is being partially blamed for a nearly 70 percent reduction in the species’ numbers that occurred in the years between 2001 and 2013. The status of the penguins led to experimental fishing closures around four colonies between 2008 and 2014.
The newly published study is the first to demonstrate that such experimental closures could have a beneficial impact on the demographics of the penguin population. While the Robben Island closure did improve chick survival, however, the population will not be able to fully recover unless more is done to limit the fishing of sardines in the region.
Penguins and other seabirds sometimes respond to a lack of food by abandoning breeding, opting not to relay eggs after they are lost, or bringing less food to their chicks, thus hampering their ability to grow and harming their overall health. Dr. Sherely’s team reported seeing all of these behaviors in African penguins over the past several years.