The emperor penguin is the tallest and heaviest of all living penguin species and is endemic to Antarctica.

It is the only penguin species that breeds during the Antarctic winter.

Like all penguins, it is flightless, with a streamlined body, and wings stiffened and flattened into flippers for a marine habitat.

Its diet consists primarily of fish, but also includes crustaceans, such as krill, and cephalopods, such as squid.

The female lays a single egg, which is incubated for just over two months by the male.

The emperor penguin breeds in the coldest environment of any bird species.

The emperor penguin has been kept in near threatened category by the IUCN.

The emperor penguin is a social animal in its nesting and its foraging behaviour.

As a defence against the cold, a colony of emperor penguins forms a compact huddle (also known as the turtle formation) ranging in size from ten to several hundred birds, with each bird leaning forward on a neighbour.

What are the causes for an increased risk to emperor penguin species?

The primary causes for an increased risk of species endangerment are declining food availability, due to the effects of climate change and industrial fisheries on the crustacean and fish populations.

Other reasons for the species’s placement on the Endangered Species Act’s list include disease, habitat destruction, and disturbance at breeding colonies by humans. Of particular concern is the impact of tourism.

Is there any link between loss of sea ice and emperor penguin population viability?

There has been found a clear link between negative sea ice anomalies and emperor penguin breeding failures with grave consequences for emperor penguin population viability.

Since 2016, the Antarctic sea ice extent — the total region with at least 15% sea-ice cover — has been shrinking with the total area of frozen water around the continent reducing to new record low levels almost every year. This puts more than 90% of emperor penguin colonies at risk as they may go extinct by the end of this century, if Earth continues to get warmer at the present rate.

As a result of the loss of sea ice, the penguin chicks are unable to develop their waterproof adult wings and regulate their body temperature. This leads to their vulnerability to drowning or freezing to death.

How the role of stable sea ice in the emperor penguin breeding cycle is crucial?

The role of stable sea ice in the emperor penguin breeding cycle is crucial. Emperor penguins spend their whole breeding cycle on the sea ice. They need it to last from early April until late December.

The birds arrive from the sea to their preferred breeding sites on sea-ice in late March to April. They court and mate, and then lay eggs in May and June. Eggs hatch in August after which parent emperor penguins take turns to feed their chick.

The chick grows quickly and by December starts to lose its grey downy feathers and replaces them with sleek black waterproof adult plumage.

By late December or early January, the fledgling period comes to an end, leading chicks to go into the water and look for food themselves.

Therefore, the sea ice on which emperor penguins breed needs to remain stable between April to January to ensure successful breeding.