All current predictions for the future of Emperor Penguns, Aptenodytes forsteri, suggest that the species is in serious trouble, due to the effects of anthropogenic climate change, with predictions suggesting that all known colonies will be extinct or quasi-extinct (the point at which a population has shrunk so much that it is unlikely to be able to recover) by the end of the century if carbon dioxide emissions continue to rise at the current rate. If conservation measures are to be developed which will give the species any hope of survival, then monitoring Emperor Penguin colonies is essential. However, the extremely remote location of these colonies makes observing them from the ground impractical. This has caused scientists studying Emperor Penguins to turn to satellite imagery as a way to detect and monitor colonies of these Birds. This has proven to be a useful method not just for monitoring the health of Penguin colonies, but also of discovering new ones, with eight new colonies located in 2019, using data from the European Space Agency's Sentinel-2 satellite.
In a paper published in the journal Antarctic Science on 20 January 2024, Peter Fretwell of the British Antarctic Survey reports the discovery of four new Emperor Penguin colonies, using imagery from Sentinel-2 and Maxar WorldView.
The first new colony described by Fretwell lies on the Dronning Maud Land coast on the northern side of the Lazarev Ice Shelf, and is tentatively named the 'Lazarev North Colony'. A colony has previously been recorded on the Lazarev Ice Shelf. This colony known as the 'Lazarev Colony' was first observed by the Soviet Antarctic Survey in 1959, and was subsequently found in a number of satellite images. However, it has not been seen since 2014, and was recorded as being extinct in 2019.
Fretwell considers it highly likely that the Lazarev North Colony is a relocated remnant of the old Lazarev Colony. The oldest image in which it is visible dates to 2018, and it can be seen in images from 2019, 2020, 2021, and 2022, although it is not present in all images over this period. No very high-resolution images of this colony, which would enable an estimate of the population size, but it appears to be significantly smaller than the Lazarev Colony in 2014, which contained about 4500 pairs of breeding Penguins. Fretwell suggests the colony may have relocated due to the extension of the ice tongue or a change in sea-ice conditions.
The second new colony is located at Verleger Point on the coast of Marie Byrd Land in West Antarctica. This colony is visible in all Sentinal-2 images of the region from 2018 to 2022, and is also visible in the higher resolution Maxar WorldView images, allowing the size of this colony to be estimated at about 500 pairs of Birds. \The colony is about 53 km to the east of the abandoned Soviet Russkaya research station, which was abandoned in 1990, although if the scientists at this base ever made observations of Penguins in the area, they did not publish them.
The third new colony is located on the eastern side of the West Ice Shelf. It is some way offshore, on stable fast ice which has formed around icebergs which have grounded on the shallow seas of the area. This colony is located about 65 km to the east of the Karelin Bay colony and about 180 km to the west of the Burton Glacier Ice Shelf colony, with all three colonies appearing to exist at the same time. Another colony was reported at Gaussberg, about 150 km from the new colony, in 1958. This colony appears to have subsequently vanished, making it possible that one of the current populations is in fact this colony relocated. However, since the closest population to the old Gaussberg colony site id the Burton Glacier Ice Shelf colony, Fretwell feels it is unlikely that the new colony is that colony, and suggests that this is instead a well-established colony, which was missed in earlier surveys because it is so far from shore. Because there is already a colony named for the West Ice Shelf, Fretwell names this colony the 'Vanhoeffen Colony' in honour of Ernst Vanhoeffen, the biologist on board the First German South Polar Expedition of 1901-1903.
The Vanghoeffen Colony is visible in all Sentinal-2 images from 2018-2022, as well as in very high-resolution Maxar WorldView images, allowing an estimate of the size of the colony to be made, at about 5000 breeding pairs of Penguins.
The final new colony described is located on the northten side of the Gipps Ice Rise, which itself forms the southern margin of the Larsen C Ice Shelf. This is a noteworthy discovery, as no colony has been discovered between the Jason Peninsula and Dolleman Island until now, despite a number of searches.
This colony is extremely small, estimated at about 200 breeding pairs of Penguins, and located in an area which is often obscured by cloud cover, making it extremely hard to detect in satellite images, although once identified it could be found in Maxar WorldView images dating back as far as 2016. The colony was located against ice cliffs or in a small ice creek north of the ice rise, until 2021, when the calving of a large ice berg changed the topology of the region, forcing the Penguins onto open fast ice, where the colony became easier to detect.
The discovery of the four new colonies, together with the re-discovery of a colony at Umbeashi in Amundsen Bay, which was thought to be extinct in 2019, but reformed in 2021 and 2022, brings the number od known Emperor Penguin colonies to 66, as well as filling several gaps in the distribution of these Birds. Despite this, it only raises the known global population of Emperor Penguins by about 5700 pairs. Given that the former Lazarev Colony was thought to comprise about 4500 pairs, and the new Lazarev North Colony is thought to be much smaller, this probably does not represent a major increase in the total Emperor Penguin population.
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