On the 19th September 2005, the project Marine IBA's initiated aerial censuses of marine birds along the Portuguese coast that give an almost instantaneous image of their distribution along the coastal strip. The data obtained are compared with those obtained from the boat censuses and allow the detection of the occasional errors in the two methods (boat and aerial censuses). For some species that actively move away from the boats whilst at a great distance, this is the best method for detection and inclusion in the census.
The support of the Aeroclube of Lisbon has been essential in the execution of these search flights, which allow us to cover a coastal strip 20 nautical miles wide from the North to the South of the country. The aerial transects are made at an altitude of around 150m (500 ft) and require two pilots for safety reasons, as such low altitude flying demands high levels of air safety. The remaining two seats of the Skyhawk we use (a single motor plane with raised wings) are occupied by two observers who take continuous counts of the areas of sea below. These flights have already detected 12 species of birds and two marine mammals (Fin Whale Balaenoptera physalus and Common Dolphin Delphinus delphis ), and also Balaeric Shearwater Puffinus mauretanicus , Northern Gannet Sula bassana e Cory's Shearwater Calonectris diomedea . |