A new study has proven that African penguins benefit when there is a greater abundance of fish available and it can be used to inform fisheries management in future.
The three-year study looked at a colony on Robben Island during a period when the area was closed to commercial fishing and monitored the health of the birds as well as the effects on the surrounding fish populations.
The researchers fitted the adult penguins with small cameras for a rare glimpse into their underwater behaviour.
The study found a direct link between the abundance of anchovy and sardine, and the penguins' foraging behaviour and the condition of their offspring.
Dr Kate Campbell, who led the research at the University of Cape Town as part of her PhD project, said the closure of commercial fisheries created a "unique opportunity to study how African penguins directly respond to natural changes in local abundance of their prey - anchovies and sardines".
Co-author Katta Ludynia told News24 the results clearly show the birds benefit when there's more fish around.
Although this is hardly surprising, Ludynia said it's important to have proof.
"If there's a lot of fish around an island, it doesn't mean that the birds actually have access to the fish because the fish might be taken out by the fisheries."
"So basically, the fish that was around was available to the birds, and we could show the more fish there is, the better the birds do - which is not a new thing, but it's very good to be able to actually prove it..."
Ludynia added that the study is highly relevant at the moment as the endangered African penguin continues to decline, with 2018 seeing the lowest ever recorded numbers of breeding pairs in South Africa.
The scientists say the small predators can also help inform fishery management and marine conservation efforts in future.
"The African penguin is a good indicator of the situation of our oceans, as this study shows, and unfortunately it is not showing us a great picture at the moment," Ludynia said.
The study was published in the Journal of Applied Ecology this week.