Most Antarctic animals and plants are set to decline by 2100

Under a business-as-usual-scenario, 65 per cent of land animals and plants in the Antarctic will decline by the end of the century, with emperor penguins among those that will endure the steepest population loss

By Corryn Wetzel

Around 65 per cent of Antarctic animals and plants could decline by the end of the century if conservation efforts aren’t ratcheted up. Species expected to undergo the steepest population drops are emperor penguins, Adélie penguins, chinstrap penguins and soil nematodes.

In a two-part analysis, Jasmine Lee at the British Antarctic Survey and her colleagues compiled scientific data to pinpoint which of the Antarctic’s wildlife will be most at risk under moderate and severe warming scenarios. Then, they asked a group of 29 international experts on Antarctic biodiversity to assess the cost and effectiveness of different management strategies over the next century, like reducing tourism and the spread of invasive species.

Under current management strategies and moderate warming, the team found 65 per cent of land plants and animals will decline by the end of the century. If warming is limited to below 2°C by 2100, the estimate drops to 31 per cent. “Everyone tends to think of Antarctica as this remote and untouched wilderness that’s free of these threats that are facing the rest of the world,” says Lee, but the results suggest otherwise.

Seabirds were slated to endure the steepest declines, with emperor penguins (Aptenodytes forsteri) losing 90 per cent of their population by 2100, largely because they rely on ice for breeding. Dry soil nematodes and Adélie penguins (Pygoscelis adeliae) are expected to decline by more than half. Not all species suffered from climate change: some native flowering plants are expected to spread with warmer temperatures and more available liquid water.

Finally, the 29 experts collectively identified 10 key steps to reduce the most severe damage at an annual cost of $23 million – excluding the cost of addressing climate change – that could benefit up to 84 per cent of plants and animals. The most promising solutions were increasing habitat protection for vulnerable species, managing the spread of disease and reducing the introduction of invasive species.

Despite the challenges facing emperor penguins, Lee says this doesn’t mean the species is fated for certain extinction. “I hope we can mitigate climate change enough that that’s not the kind of future we will see,” she says.

Journal reference: PLoS Biology, DOI: 10.1371/journal.pbio.3001921