Se informa de los resultados de relevamientos avíales en las islas Grevy, Bayly, Wollaston y Deceit del archipiélago del Cabo de Hornos, realizados en primavera y verano entre 1980 y 1982. Se efectuaron censajes separados por ambientes de Litoral-Océano, Bosque Costero, Bosque Interior, Turbosos, Saxícolas y Lacustres. Se calculó riqueza específica, diversidad y uniformidad, para cada ambiente y para el conjunto de ambientes terrestres de cada isla. Se calcularon índices de similitud y se hicieron análisis de grupos recurrentes entre islas. Los índices de riqueza específica y de diversidad para el ambiente de Litoral-Océano fueron mayores en la isla Deceit, que es la más alejada del continente de las estudiadas; en cambio, para los ambientes terrestres estos índices fueron mayores en la isla Grevy que es la más cercana. Los menores valores se obtuvieron en la isla Wollaston, no obstante ser la más grande todas las del grupo estudiado.
Results of avian surveys in the islands Grevy, Bayly, Wollaston and Deceit of the Cape Horn archipelago, carried on during spring and summer between 1980 and 1982 are reported. Separate censuses for different environments such as Littoral-Ocean, Coastal Forest, Interior Forest, Bog, Saxicolus and
Lacustrine were held at each island. Species richness, diversity and uniformity were calculated for each environment and also for the terrestrial environments as a whole on each island. Similarity indices and recurrent groups between islands were also analysed. Species richness and diversity indices, calculated for the Littoral-Ocean samples, were higher at Deceit, which is the farthest island from the continent of the studied ones; conversely, for terrestrial habitats these indices were higher at Grevy, which is the nearest. The lower values were obtained at Wollaston, notwithstanding of being the bigger island of the studied group.