Satellite tracking of the winter migration of Magellanic Penguins Spheniscus magellanicus breeding in the Falkland Islands

Magellanic penguin populations in the Falkland Islands may have decreased o ver the past decade. The post-breeding migration may be the period in which the birds are most vulnerable. To investigate this we equipped ten Magella nic Penguins after their moult at Seal Bay (51 degrees 38'S, 58 degrees 03' W), East Falkland, with satellite transmitters. The movements of the pengui ns were tracked for between 15 and 99 days until transmission ceased. All b irds initially migrated to the northwest. However, four birds entered Argen tinean coastal waters, then headed northeast following the coastline. The o ther penguins remained offshore, but also changed to a northeasterly course . Two birds migrated beyond 36 degrees S with a maximum distance to the col ony of more than 1800 km, while the minimum distance travelled was up to 27 00 km. Initially, the birds migrated quickly but their speed was reduced an d became more variable as time progressed. A high concentration of position al fixes, associated with low travelling speeds, indicated at least four di fferent areas where birds were assumed to forage efficiently. The relevance of these areas is discussed with respect to the diet of Magellanic Penguin s and possible interactions with human activities.