Data for the conservation and protection of seabirds in the Southern Ocean
Variations in the population size of 7 species of marine predators in the Southern Ocean. Data from the observatory show contrasting trends over the whole period, with populations declining (4 species including the yellow-billed albatross in red) while one is stable (the black-browed albatross in goose pook-green) and 2 are increasing (like the Amsterdam albatross in dark green).
Nest Counting and Data Analysis
To count the nests of nesting birds, scientists take aerial images using a kite. On this picture it is a colony of gorfous macaroni in Kerguelen. By enlarging the picture it is possible to count the number of pairs of birds and to compare the breeding success of this species from one year to another.
Life story of a snow petrel
Banding makes it possible to follow the fate of individuals throughout their lives because seabirds are very loyal to their colony and nest. The example below shows the life history of a snow petrel in Terre Adélie wearing ring n°FL11617 between 1982 and 2013. The life histories of all banded individuals are coded as 0 (not seen that year) and 1 (seen that year), making it possible to calculate the proportion of individuals that survive from one year to the next in the population. For snow petrels, the annual survival rate varies around 95%, which corresponds to an average life expectancy of about 30 years. Tracking banded individuals also makes it possible to calculate the number of juveniles reared over the course of a lifetime. For example, individual FL11617 reared 17 chicks between 1982 and 2012.