Emperor penguins are in danger of dramatic declines by the end of the century due to climate change as melting sea ice will have a ripple effect on the iconic animal's food chain, a new research has warned.
The study proposes that the Emperor penguins are "fully deserving of endangered status due to climate change."
Emperor penguins are heavily dependent on sea ice for their livelihoods, and, therefore, are sensitive to changes in sea ice concentration (SIC).
The researchers' analysis of the global, continent-wide Emperor penguin population incorporates current and projected future SIC declines, and determined that all of the colonies would be in decline - many by more than 50 per cent - by the end of the century, due to future climate change.
"If sea ice declines at the rates projected by the IPCC climate models, and continues to influence Emperor penguins as it did in the second half of the 20th century in Terre Adelie, at least two-thirds of the colonies are projected to have declined by greater than 50 per cent from their current size by 2100," said lead author of study Stephanie Jenouvrier from the Woods Hole Oceanographic Institution (WHOI).
"None of the colonies, even the southern-most locations in the Ross Sea, will provide a viable refuge by the end of 21st century," Jenouvrier said.
Researchers have been returning to Terre Adelie, in eastern Antarctica, every year to collect biological measurements of the penguins there, charting the population's growth (and decline), and observing their mating, foraging, chick-rearing patterns.
"The role of sea ice is complicated," added Jenouvrier.
"Too much ice requires longer trips for penguin parents to travel to the ocean to hunt and bring back food for their chicks. But too little ice reduces the habitat for krill, a critical food source for emperor penguins. Our models take into account both the effects of too much and too little sea ice in the colony area," said Jenouvrier.
The researchers found that, while some colonies will increase for a while, this growth is short-lived. By the end of the century at least two-thirds of them will have declined by more than half.
Of even more concern, all of the colonies are projected to be declining by that time. Although current climate models do not look further into the future than that, a dramatic change would be required to reverse these declines.
"We propose that the Emperor penguin is fully deserving of endangered status due to climate change, and can act as an iconic example of a new global conservation paradigm for species threatened by future climate change," the study authors said.
The study was published in the journal Nature Climate Change.
