Warmer winds a boost to easy-rider albatross

Stronger winds over the Southern Ocean around Antarctica have helped the wandering albatross fly faster and breed more successfully, European scientists said on Thursday. However, the study published in the US journal Science cautioned that those benefits may be short-lived if the globe continues to warm and wind speeds shift further in the coming decades. The study focused on four decades of data on a population of albatrosses on the windy Crozet islands, beginning in 1966. Scientists began fitting the snow-colored wind-riders -- with the largest wingspans of any living bird averaging about three meters or 10 feet -- with satellite transmitters in 1989 to track their movements. Over time, they found that an increase in atmospheric pressure, likely a result of warming temperatures, has boosted wind speeds over this particular sector of the western Indian Ocean where the birds roam. And the albatrosses have responded in kind, flying faster, growing fatter by an average of one kilogram (half pound), spending less time foraging for food, having more babies, and extending their range further southward. "Wandering albatrosses appear so far to have benefited from wind changes occurring in the Southern Ocean, with higher speeds allowing for more rapid travel," said the study, noting a marked change in the 2000s over the 1990s. "In wandering albatrosses the probability of prey encounter and capture is related to the daily distances individuals are able to cover." The birds' beefier size was "one of the most unexpected changes we observed over the past 20 years," added the study. The weight gain was likely due to improved access to food but could also be a structural adaptation by the birds, who may be exploiting their increased mass to maximize their flight ability in windier zones. But if current trends continue, the winds could become too fast for the albatrosses and by 2080 their habit of foraging over the Crozet Islands may prove impractical. "Travel and flight speeds will not respond linearly to the increase in wind speed, and too strong gales winds become unfavorable for dynamic soaring flights," said the research. The study was led by Henri Weimerskirch and colleagues at the Centre d'Etudes Biologiques de Chize in Villiers en Bois, France; and Maite Louzao of the Helmholtz Centre for Environmental Research in Leipzig, Germany.