In a concerning development, researchers have discovered that penguins in Antarctica have radically shifted their breeding seasons, seemingly in response to the effects of climate change. The decade-long study, led by Penguin Watch at the University of Oxford and Oxford Brookes University, has revealed dramatic changes in the behaviour of three penguin species – Adélie, chinstrap, and gentoo.
The findings, published in the Journal of Animal Ecology, show that the timing of the breeding season for all three species has advanced at record rates. Gentoo penguins have exhibited the most significant change, with an average advance of 13 days over the past decade and up to 24 days in some colonies. This represents the fastest change in breeding phenology recorded in any bird, and possibly any vertebrate, to date. Adélie and chinstrap penguins have also advanced their breeding by an average of 10 days.
“We are very concerned because these penguins are advancing their seasons so much, and penguins are now breeding earlier than in any known records,” said the report’s lead author, Dr Ignacio Juarez Martínez. “The changes are happening so fast that the penguins could end up breeding at times when their prey is not available yet. This could result in a lack of food for the penguin chicks in the first weeks of their life, which could be fatal.”
The researchers gathered evidence from 77 time-lapse cameras positioned around 37 colonies in Antarctica and some sub-Antarctic islands. They found that the shifting breeding periods could also result in increased competition between the region’s penguin species, with some species potentially emerging as “winners” and others as “losers.”
“Gentoos are a more temperate species and are already benefiting from the milder conditions that climate change is bringing to Antarctica,” explained Juarez. “They’re already expanding their colonies throughout the peninsula and growing their numbers in colonies that were already established, while Adélies and chinstraps are both declining throughout the Antarctic peninsula.”
The scientists warn that these drastic changes in penguin breeding patterns could have far-reaching consequences for the Antarctic ecosystem. Penguins play a crucial role in the food chain, bringing nutrients from deep water up to the surface, which is vital for the completion of photosynthesis by algae.
“We’ve already seen gentoos take nests that were previously occupied by Adélies or chinstraps,” said Juarez. “Losing several species of penguins before the end of the century, as models predict, could be a fatal blow to the functioning and resilience of the Antarctic ecosystem.”
The researchers emphasize the urgent need to preserve penguin diversity in Antarctica, as the changing climate continues to disrupt the delicate balance of the region’s ecosystems.
