Climate change has marked effects on global weather patterns and oceanic systems, impacting animal behaviour and fitness in potentially profound ways. Despite this, we lack detailed information about species’ responses to climatic variation. Using an 11-year tracking dataset of over 300 individual birds, we explore the consequences of variation in the Southern Annular Mode (SAM) and Southern Oscillation Index (SOI) for individual behaviour and fitness in wandering albatrosses Diomedea exulans breeding in the Southern Indian Ocean. Our results reveal distinct responses between males and females to climatic variation that align with the impacts of each climatic index on the distinct foraging ranges of each sex. In positive SAM phases, linked to poorer foraging conditions in female ranges and better conditions in male ranges, females exhibited behaviour consistent with reduced foraging success: that is, fewer prey capture attempts, and more movement between feeding patches. Males, on the other hand, showed no behavioural change. During positive SOI phases, associated with good foraging conditions in both male and female foraging ranges, both sexes showed evidence of more successful foraging, with birds engaging in more search behaviour, and taking shorter trips with fewer prey capture attempts, together indicating increased food intake per unit time. We found limited evidence for a role of individual variation, as measured through differences in personality, suggesting that plastic responses to climate are sufficiently important so as to obscure inter-individual variation. Supporting this was the finding that individual breeding success was unaffected by climatic variation, suggesting that plastic foraging behaviour allows albatrosses to mitigate climate impacts and maintain reproductive output.
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This content will become publicly available on November 1, 2025
Strong winds reduce foraging success in albatrosses
Knowledge of how animals respond to weather and changes in their physical environment is increasingly important given the higher frequency of extreme weather recorded in recent years and its forecasted increase globally 1,2. Even species considered to be highly adapted to extremes of weather, as albatrosses are to strong winds 3–5, may be disadvantaged by shifts in those extremes. Tracked albatrosses were shown recently to avoid storms and the strongest associated winds 6. The drivers of this response are so far unknown, though we hypothesise that turbulent storm conditions restrict foraging success, possibly by reducing the detectability or accessibility of food, and albatrosses divert towards more profitable conditions where possible. We tested the impact of physical environment - wind speed, rainfall, water clarity, and time of day - on feeding activity and success of two species of albatrosses with contrasting foraging strategies. We tracked 33 wandering and 48 black-browed albatrosses from Bird Island (South Georgia) with GPS and immersion loggers, and 19 and 7 individuals respectively with stomach-temperature loggers to record ingestions, providing an in-depth picture of foraging behaviour. Reduced foraging profitability (probability of prey capture and overall mass) was associated with stormy conditions, specifically strong winds and heavy rain in surface-seizing wandering albatrosses, and probability of prey capture was reduced in strong winds in black-browed albatrosses. We show that even highly wind-adapted species may frequently encounter conditions that make foraging difficult, giving context to storm avoidance in albatrosses.
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- Award ID(s):
- 1951500
- PAR ID:
- 10553891
- Publisher / Repository:
- Elsevier Inc
- Date Published:
- Journal Name:
- Current Biology
- ISSN:
- 0960-9822
- Subject(s) / Keyword(s):
- animal behaviour biologging climate impacts extreme weather seabirds
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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