113 Emperor Penguins at Halley Bay

What this episode covers

Watch this on video Buy us a coffee: Chris / Henry Emperor penguins are probably one of the most difficult animal species to reach, as they are true Antarctic penguins that spend the winter on the ice around the southern continent to hatch their young. They breed in large colonies, the largest ones being at Coulman Island in the Ross Sea and at Halley Bay in the Weddell Sea. Over the past 60 years that researchers have been observing the Halley Bay colony, between 14,300 and 23,000 pairs have flocked to the site’s sea ice to breed. But since 2016, breeding failures have been “catastrophic” and the penguins appear to have abandoned what was once a reliable haven. In 2015 the strongest El Niño in decades began disrupting Halley Bay’s “fast ice,” that is anchored to the shore or ocean floor. Between April and December, the penguins depend on fast ice to provide stable ground for mating, incubating eggs and caring for chicks. But in 2016, the ice broke apart before the baby penguins would have developed the feathers they needed to swim. Thousands of them appear to have drowned. The ice failed to properly reform in 2017 and 2018, leading to the death of almost all the chicks at the site each season. And now, the colony at Halley Bay has largely disappeared. The Brunt Ice Shelf at the colonies' edge is traversed by a crack. Previously stable for about 35 years, this crack recently started accelerating northward last year as fast as 4 kilometers per year. Today the large Chasm 1 crack is only [within a few kilometers]((https://www.abc.net.au/news/2019-10-09/formation-of-brunt-ice-shelf-iceberg-in-antarctica-captured/11370748?nw=0) of the McDonald Ice Rumples and the Halloween crack. If the cracks merge, the area of ice lost from the shelf will likely be at least 1700 square kilometers (660 square miles). It seems that many of the adult emperor penguins have travelled elsewhere to find more reliable breeding ground. Satellite data shows that a colony of emperor penguins at the nearby Dawson-Lambton Glacier suddenly experienced a “massive increase” in numbers starting in 2016. At the same time, scientists have been looking for new colonies for the last 10 years. Through satellite mapping technology they know have located 11 previously unknown emperor penguin colonies based on mapping the brown-red guano stains the birds leave on the ice. So it's literally the penguin poo seen by satellites that leads to the discovery of these previously unknown emperor colonies in Antarctica. There are now known to be 61 emperor penguin colonies scattered around the continent.