‘Breeding failure’ for thousands of emperor penguin chicks over last three years

New research has found that emperor penguin chicks in Antarctica have been wiped out due changes in sea-ice conditions.

Emperor penguins at the Halley Bay Colony have failed to raise chicks for the last three years due to changes in the local sea-ice conditions. Emperor penguins need stable sea-ice from April to December on which to breed on.

Until recently, the Halley Bay colony was the second largest in the world, with the number of breeding pairs varying each year between 14,000 and 15,000. For the last 60 years, the sea-ice conditions have been stable.

However in 2016, after stormy weather, sea ice broke up in October, well before any chicks would have fledged. This occurred again in 2017 and 2018, resulting in the death of almost all chicks at the site each season. Today, the colony at Halley Bay has all but disappeared.

Lead author and BAS remote sensing specialist Dr Peter Fretwell said: “We have been tracking the population of this, and other colonies in the region, for the last decade using very high resolution satellite imagery. These images have clearly shown the catastrophic breeding failure at this site over the last three years. Our specialised satellite image analysis can detect individuals and penguin huddles, so we can estimate the population based on the known density of the groups to give reliable estimate of colony size.”

Scientists from the British Antarctic Survey (BAS) used high resolution satellite imagery to reveal the unusual findings. Going forward, this imagery will allow them to gain vital information about how this iconic species may cope with future environmental change.

Antarctica is rapidly changing. A recent report by NASA and the University of California, Irvine has found that ice mass in Antarctica has been declining rapidly over the last 40 years.

The research team were able to determine that between 1979 and 1990, Antarctica shed an average of 40 gigatonnes of ice mass annually. From 2009 to 2017, about 252 gigatonnes per year were lost.

This is resulting in a rapidly changing environment for the continent. BAS penguin expert and co-author Dr Phil Trathan, said: “emperor penguins numbers are set to fall dramatically, losing 50-70% of their numbers before the end of this century as sea-ice conditions change as a result of climate change.”

Photograph: Fguerraz