Time is almost up for the African penguin: Double blow of overfishing and climate change may kill them off

Research conducted by University of Exeter suggests penguins are in peril
Young birds are being forced to fish in waters with scarce stocks
Rapid changes in climate as well as overfishing are to blame, report says
Computer models shows breeding is 50 percent lower due to ecological 'trap'

Published: 13:43 EST, 9 February 2017 | Updated: 13:43 EST, 9 February 2017

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Time could almost be up for a species of penguin being driven to extinction, according to new research.

African penguins search large areas of ocean off the coast of southwest Africa for signs which usually indicate an abundance of prey.

But over-exploitation of fishing stocks, warming seas and changing salinity now lead the young birds into an 'ecological trap', forcing them to search in the wrong places to find food.

Over-exploitation of fishing stocks, warming seas and changing salinity could spell the end for the African penguin. New research by the University of Exeter suggests breeding is 50 percent lower due to an ecological 'trap'

African penguins look for areas of low sea temperatures and high chlorophyll-a, which indicate the presence of plankton and the fish which feed on it.

But climate change and industrial fishing have depleted fish stocks in these areas.

What were once reliable cues for prey-rich waters are now leading youngsters, leaving colonies for the first time, to feed in seas devoid of fish.

And they are not adapting to the man-made changes caused to their environment, the new study warns.

The study, which was published in the journal Current Biology, used satellite trackers on 54 juvenile penguins from eight colonies covering the species' breeding and feeding grounds off the coast of Namibia.

Small changes in the temperature and salinity of the waters in the area, known as the Benguela ecosystem, have caused the species to move their feeding ground hundreds of kilometres to the east.

The changes are decimating numbers, with computer models suggesting breeding is 50 percent lower than if the birds were able to escape the 'trap'.

The African penguin, previously known as the jackass penguin, is already listed as endangered by the International Union for Conservation of Nature

THE STUDY

Juvenile African penguins look for areas of low sea temperatures and high chlorophyll-a, which indicate the presence of plankton and the fish which feed on it.

The study used satellite trackers on 54 juvenile penguins from eight colonies covering the species' breeding ground off the coast of Namibia.

Small changes in the temperature and salinity of the waters in the area, known as the Benguela ecosystem, have caused the species to move their feeding ground hundreds of kilometres to the east.

The changes are decimating numbers, with computer models suggesting breeding is 50 percent lower than if the birds were able to escape the 'trap'.

Research Fellow Dr Richard Sherley, of the Environment and Sustainability Institute at the University of Exeter, led the study.

He said: 'When the young of this endangered species leave the colony for the first time, they travel long distances, searching the ocean for certain signs that should mean they have found an area with lots of plankton and plenty of the fish that feed on it.

'But rapid shifts caused by climate change and fishing mean these signs can now lead them to places where these fish, the penguins' main prey, are scarce with impacts on their survival - a so-called 'ecological trap.'

'Protecting the penguins, and other species, from falling into similar ecological traps will require better action to account of the needs of predators in managing fisheries and concerted action to tackle climate change.'

Research Fellow Dr Richard Sherley, of the Environment and Sustainability Institute at the University of Exeter, who led the study

The African penguin, previously known as the jackass penguin, is already listed as endangered by the International Union for Conservation of Nature.

It said the species is 'undergoing a very rapid population decline' which shows 'no sign of reversing.'

Dr Sherley added: 'The penguins still move to where the plankton are abundant, but the fish are no longer there.

'In particular, sardines in Namibia have been replaced in the ecosystem by lower-energy fish and jellyfish.

'Climate change and fisheries are transforming the oceans, but we don't have a complete understanding of their impact.

'Our results support suspending fishing when prey biomass drops below certain levels, and suggest that mitigating marine ecological traps will require major conservation action.'