Surging Population of Gentoo Penguins Over Other Species in Antarctica Is Not a Good Sign- Scientists Warn
Scientists have observed an unusual surge in the population of Gentoo penguins in Antarctica that poses a threat to the existence of the other penguin species. A 2016 report addressed the rising heat temperatures and anticipated the year to be “the hottest” on record. The most affected were some penguin species, specifically Adelie, who are more sensitive to climate change than Gentoo penguins, per EuroNews.
The population of Chinstraps and Adelie penguins was in decline in the Antarctic regions due to the warming climates, as per BoredPanda. However, the Gentoo species reportedly adapted to the changing temperatures quite impressively and even inhabited the newly exposed areas from the melting glaciers. Even though the melting ice in the Antarctic Peninsula allows all penguins to travel farther for breeding purposes, Gentoo penguins have risen to the occasion better than other species.
Another study closely observed the population size of the three penguin species over a 38-year period at Signy Island, South Orkney Islands, per the National Library of Medicine. Researchers compared the data of breeding pairs over the whole island from 1978 to 2016 and found the population of Gentoo penguin pairs increased by 255% (3.5% per annum) whereas Chinstraps declined to 68% (-3.6% per annum) and Adelies by 42% (-1.5% per annum).
Gentoo and Adelie penguins witnessed phases of population changes while Chinstraps consistently declined over the past four decades sparking concerns among scientists. “The gentoo penguin is a climate change winner, with populations moving farther south than we have ever seen them,” said Michael Wethington, a Stony Brook University graduate. He said that new colonies were viewed as rare occurrences but have been spotted in the past decade, per a report by NASA’s Earth Observatory. Besides climate change and habitat expansion, experts highlighted another aspect that is detrimental to the penguin species. Krills have been the main food source for penguins but their abundance has fallen over the last 50 years.
Krills are reliant on sea ice for habitat and food like algae and phytoplankton but the melting glaciers are a risk to their populations. Nevertheless, Gentoos are highly adaptable to a flexible diet in addition to climate changes. Thus, the krill scarcity does not affect their survival while the same cannot be said for Chinstraps and Adelie. These two species are greatly dependent on the marine crustaceans for food. Increased fishing activities in the Antarctic regions have also contributed to the falling krill density.
A 2021 study compared data between fishing activities and the Southern Annular Mode, which indicates climate change in Antarctica, with penguin population records. Scientists found that increased fishing during the non-breeding period impacted both Chinstrap and Gentoo numbers, adding to the negative population growth rates. Fishing organizations also net significant amounts of krill to supply animal feed demands and convert it into omega-3 dietary supplements for human consumption.
Competition from whales and seals for krill was also considered a contributing factor in the declining penguin populations in a different study from 2020, published in the journal Scientific Reports. All in all, the rapidly melting ice glaciers and warming climates are causing an imbalance in the natural weather conditions, also causing the sea levels to rise. A report by the Antarctic and Southern Ocean Coalition addressed how the global climate crisis is hindering natural processes in the region and treading towards catastrophic change that will surely impact humans in the long run.