Researchers on Crozet fit a transmitter on a wandering albatross. (credit David Gremillet/CNRS)
As the climate changes and redirects the worlds wind currents one group of birds are benefitting from the new patterns. The albatross appears to be gaining weight despite spending less time foraging and is also seeing better breeding success.
A new study seems to suggest that a changing climate may not be all bad for some species of birds – at least in the short term. The study, from the Helmholtz Association of German Research Centre and the French National Centre for Scientific Research, suggests that changing wind speed and directions are allowing albatrosses to spend more time looking after their chicks and less time out looking for food.
Westerly winds move south with climate change.
The changing climate has seen air currents in the albatrosses range increase in speed and head further south. This has allowed the albatross to fly faster and get to well stocked feeding grounds quicker. The result is that the average recorded weight of albatrosses has increased by a kilogramme and the females were able to spend more time incubating their eggs leading to a better breeding success rate.
Th study looked at 40 years of data about the foraging habits of albatrosses and breeding success. The researchers also looked at data from the Crozet Islands population of wandering albatrosses (Diomedea exulans) which contained 20 years worth of foraging and body mass index data.
Miniature tracking devices used to follow albatrosses.
New data was produced by using miniature tracking devices to see how albatross behaviour has changed. By tracking the albatrosses the researchers were able to determine the changing flight of the birds over the last few decades.
What they found was that female birds used more windy areas and travelled more towards the south pole.
“This means that they spend less time at sea while incubating the egg and thus the breeding success increases” explains Dr. Henri Weimerskirch of the French National Centre for Scientific Research (CNRS-CEBC).
More southerly feeding grounds reduces albatross by-catch.
The benefit of the females flying further south rather than towards the sub tropics that were their previous feeding grounds is that they are less likely to become part of by-catch of long line fishing boats.
“The wandering albatross Crozet population has decreased as a result of adult mortality on longline fishing in subtropical waters, especially females since they favour warmer subtropical waters in the north compared to the more southerly distribution of males” says Dr. Maite Louzao Arsuaga, who has been modelling albatross movement from 2009 to 2011 at the UFZ. “Due to the changing wind conditions, females are now foraging in more southward areas where such fishing is not that widespread“.
Albatrosses gain 10% in body weight.
The most surprising part of the study for the researchers was that both male and female birds now weighed about 1 kilogramme more that a couple of decades ago. This is equal to 10% extra in body weight.
With the global population of wandering albatrosses put at around 8,000 pairs these new changes in foraging behaviour and breeding success is welcome news. however it may be short-lived as some climate scientists believe that by 2080 wind patterns will have moved further south. Albatrosses would then have to fly further south to find suitable feeding grounds.
