Prof. XIE Zhouqing, from University of Science and Technology of China (USTC), together with Prof. Carlo Baroni from University of Pisa, have made progress in investigating the relationship between the Holocene penguin population and climate change. They revealed the evolution procedure of Adélie penguin habitat in Enkesburg Island, and the result is published in Quaternary Science Reviews .
(Adélie Penguin congregating on a ice floe, image from Encyclopædia Britannica )
Research group conducted detailed grid survey and adequate sampling of the numerous penguin breeding sites in Enkesburg Island, based on the China Antarctic Research Station. Accelerator mass spectrometry (AMS) was used to conduct Carbon-14 dating of penguin fecal sediment profiles and residual samples. An integrated study was accomplished through the combination with the relevant samples and data accumulated in the past 30 years by the team of Professor Carlo Baroni from the University of Pisa in Italy, which is shown to be a fruitful international cooperation.
The research group developed a method combining the dating and area determination of abandoned nesting areas, and systematically replayed penguin population changes and nesting area migration processes after the Holocene.
According to their research, Adélie penguins first settled in Enkesburg Island in 8600 years ago, being the earliest penguin breeding site in the Ross Sea since the Holocene. Thus, the duration of Adélie penguins’ existence was extended by 1600 years, which begins when the local glacier retreated. In other words, penguins landed and propagated there immediately after the glacier retreating.
(Reconstructing the evolution of penguin colony distribution during the historical period in the Ross Sea, Image from the team)
The study suggests that the ice-free environment provided by the interglacial lakes in Tla Nova Bay allowed Enckelsberg Island to host migrating penguin populations from the Scott Coast during a period of nearshore sea ice expansion, serving as a valuable refuge for regional penguins.
Furthermore, this paper put forward that nearshore sea ice in the Ross Sea has been increasing in recent decades, so areas with interglacial lakes, such as Enckelsberg Island, will play a more critical role in the continuation of penguin populations.
(Written by ZHANG Boxian, edited by LIU Zige, USTC News Center)