Overview
- Adélie and chinstrap colonies now settle about 10 days earlier on average, while gentoos advanced roughly 13 days per decade and up to 24 days at some sites between 2012 and 2022.
- Authors describe the change as the fastest documented phenological shift in any bird, drawn from 77 time‑lapse cameras at 37 colonies and millions of volunteer image annotations.
- On-site sensors show breeding locations warmed about 0.3°C per year—roughly four times the Antarctic average—with earlier settlement closely tracking these increases.
- Earlier, overlapping seasons are intensifying competition that tends to favor diet-flexible gentoos, with field reports of gentoo expansion and pressure on krill- and ice-dependent Adélie and chinstrap penguins.
- The team cautions that effects on chick survival and long-term population trends remain unclear, prioritizing continued monitoring following publication in the Journal of Animal Ecology.