Editor's choice July/August 2025

The editor’s choice is the article by Eriksen et al.: “Climatic variation affects seasonal survival of an alpine bird species”

Ecologists have only just begun to understand the potential impact of climate change on wildlife. Perhaps the most obvious response expected of cold-adapted species in alpine ecosystems is altitudinal shifts. However, while range shifts and population declines in response to warming have received much attention, this paper draws attention to the less obvious, more subtle effects of climatic variability. Lasse Eriksen and colleagues radio-tracked 272 individual willow ptarmigan over seven years in the Norwegian mountains, to model seasonal mortality risks linked to changing snow patterns. They investigated how mismatches in the timing of moulting and food scarcity might pose competing risks that vary with environmental conditions. The study revealed that an early onset of winter increased spring mortality in yearlings, whereas high spring snow levels raised mortality rates for both adults and yearlings. In autumn, only sex-based differences were observed. The authors conclude that mortality in both spring and autumn is the result of a trade-off between predation risk - exacerbated by white plumage on snowless ground - and starvation due to limited food access. Early autumn snow may also have delayed effects later in spring, particularly on young birds entering their first winter. This study highlights how climate-induced changes in snow patterns impact mountain bird survival and emphasizes the importance of including fine-scale mechanisms in population models to improve predictions under climate change.

/Ilse Storch

Editor-in-Chief

Comments