Overview
- The peer-reviewed analysis in Science Advances tracked roughly 17,000–19,000 birds on the Crozet/Possession archipelago over 24 years using RFID tags and a deep-learning model to infer mating dates.
- Average breeding now starts about 19 days earlier than in 2000, moving from roughly November 27 to November 8 by 2023.
- Chick survival increased from about 44% in 2000 to 62% in 2023, reflecting roughly a 40% gain in breeding success.
- Earlier breeding correlated with higher sea-surface temperatures and shifts in ocean productivity consistent with more lanternfish, and the birds displayed flexible foraging and diets.
- Authors and outside experts warn the advantage may be temporary as the polar front moves south and local colonies reach carrying capacity, prompting redistribution and raising the risk of future declines.