The highly mobile wandering albatrosses (Diomedea exulans) explore the Southern
Ocean around the Antarctic continent, where they spend several decades of their
life foraging, breeding and moving well over 18 000 km in one year across open ocean. They are
adapted to navigate the extreme environment open ocean and return to isolated
islands to breed. Despite this being one of the most charismatic bird species we still have had very limited knowledge about the dispersal
flights and migration of young albatrosses, but also to which zones different
populations as well as birds of different age and sexes move. Knowledge which is central for the conservation of the species.
Wandering albatross Diomedea exulans; Photo: Susanne Åkesson |
In a newly published study in PLoS ONE we tracked, by satellite
telemetry, the departure dispersal of 13 juvenile wandering albatrosses from
the Crozet Islands and compared them with tracks of 7 unrelated adults during
the interbreeding season. We used the satellite tracks to identify different behavioural
steps of the inherited migration program used by juvenile wandering albatrosses
during their first solo-migration. Our results show that the juvenile wandering
albatrosses from Crozet Islands moved to sex-specific foraging zones of the
ocean using at departures selectively the wind. The birds’ departure flights coincided
with tailwinds from southwest. The results suggest that the inherited migration
program used by the juvenile wandering albatrosses encode several distinct
steps, based on inherited preferred departure routes, differences in migration
distance between sexes, and selective use of winds. During long transportation
flights the albatrosses were influenced by winds and both adult and juveniles
followed approximate loxodrome (rhumbline) routes coinciding with the foraging
zone and the specific latitudes of their destination areas. During the long
segments of transportation flights across open seas the juveniles selected
routes at more northerly latitudes than adults.
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