Wandering albatrosses exert high take-off effort only when both wind and waves are gentle
Résumé
The relationship between the environment and marine animal small-scale behavior is not fully understood. This is largely due to the difficulty in obtaining environmental datasets with a high spatiotemporal precision. The problem is particularly pertinent in assessing the influence of environmental factors in rapid, high energy-consuming behavior such as seabird takeoff. To fill the gaps in the existing environmental datasets, we employed novel techniques using animal-borne sensors with motion records to estimate wind and ocean wave parameters and evaluated their influence on wandering albatross takeoff patterns. Measurements revealed that wind speed and wave heights experienced by wandering albatrosses during takeoff ranged from 0.7 to 15.4 m/s and 1.6 to 6.4 m, respectively. The four indices measured (flapping number, frequency, sea surface running speed, and duration) also varied with the environmental conditions (e.g., flapping number varied from 0 to over 20). Importantly, takeoff was easier under higher wave conditions than under lower wave conditions at a constant wind speed, and takeoff effort increased only when both wind and waves were gentle. Our data suggest that both ocean waves and winds play important roles for albatross takeoff and advances our current understanding of albatross flight mechanisms. eLife assessment This fundamental study advances our understanding of seabird responses to environmental conditions, with implications for movement ecology, flight biomechanics, animal foraging, and bioenergetics. Animal-borne data-loggers are used to generate a compelling high quality dataset on animal movement and environmental conditions. The study will interest ornithologists, comparative bio-mechanists, ocean ecologists and those interested in technological advances in animal sensors.
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