According to research published on Antarctic Science a few hours ago, some emperor penguins are moving their colonies due to the melting of ice caused by climate change. Four new emperor penguin breeding sites have been identified thanks to the Copernicus Sentinel-2 and Maxar WorldView-2 satellites monitoring the emperor penguin population.
Peter Fretwell, researcher at the British Antarctic Survey, told: "The emperor penguins preferred to search for areas where the ice is more stable. The four newly discovered colonies had probably existed for many years.
They are mostly small colonies, with fewer than 1,000 breeding pairs each." The sites are located on the northern side of the Lazarev Ice Shelf and on the eastern side, on the northern slope of the Gipps Ice Rise and at Verleger Point.
The four areas identified and, together with the other Umbeashi site, bring the overall number of colonies registered in Antarctica to 66.
With the exception of a single colony, the others would number less than 1000 specimens, with lower reproductive success for the emperor penguins.
Reproduction of emperor penguins
Emperor penguins have the particularity of breeding in one of the most inhospitable regions of the world, Antarctica, during the winter. Temperatures can drop to -65°C, with winds blowing at more than 200 km/h.
Sometimes, when a nesting site becomes too windy, a colony of emperor penguins may move to a less hostile location. The emperor penguin reaches maturity at three years of age, but generally does not begin breeding until one to three years later.
The annual breeding cycle begins at the beginning of the southern winter, in March and April, when all adult emperor penguins head to the colony's nesting areas. They often have to walk 50–100 km from the outskirts of the pack ice into the hinterland.
The start of the journey seems to be induced by the decrease in the length of the days. Thus, by controlling the brightness and imitating short days, scientists induced the entry into the breeding season in captive emperor penguins.
Emperor penguins are monogamous. Pairs form throughout the breeding season. However, only 15% of couples remain faithful from one year to the next. This is due to the very short duration of the female's fertile period: for her it is more important to reproduce immediately than to wait to find her partner from the previous year