Results are provided of a population genetics study using the starch gel electrophoresis technique and concerning 22 species of seabirds from four localities of the Southern Ocean: Antarctic Continent (Adélie Land), two subantarctic islands (Crozet and Kerguelen Islands) and one subtropical island (Amsterdam Island). Concerning genetic differentiation, species classification is reviewed using data from electrophoresis: for example, populations of King Penguins Aptenodytes patagonicus from Kerguelen and Crozet Islands show a high level of isolation. For five species, electrophoretic data are compared with the preliminary results of a mitochondrial DNA study. At a higher taxonomic level, storm petrels Hydrobatidae are markedly distant from the other three families of Procellariiformes. Concerning heterozygosity, genetic variability is low in the Wandering Albatross Diomedea exulans, low on average for seabirds in general, and increases on average towards higher latitudes.