Aerial Survey

The ObSERVE Aerial project was carried out by an international consortium led by University College Cork with international partners IMARES, Alnilam and Aerosotravia.  It involved a team of trained observers flying over the sea in a specially equipped aeroplane along an extensive set of survey lines, in order to record the occurrence, distribution and numbers of whales, dolphins, porpoises and seabirds.  Other species of interest such as sharks and sea turtles were also seen and recorded.

The aerial survey track-lines were designed to be extensive and representative of a large study area (see Image below). Surveys took place during both the summer and winter seasons for a survey line coverage of 16,802km in 2015-16, and 20,295km in 2016-17.  Finer-scale aerial surveys for seabirds were also carried out in the summer, autumn and winter of 2016 in the Irish Sea.  These achieved a total survey line coverage of 6,687km.

In total the project's four combined summer and winter aerial surveys recorded, analysed and mapped almost 10,000 sightings of seabirds, representing 24 species.  A further 19 species of cetacean (i.e., whales, dolphins & porpoises) were recorded, analysed and mapped by the project team from almost 2,000 sighting records over the two-year field study.  The project's detailed observations and analyses include numerous records of rarely-seen beaked whales, which are specialised deep-diving species, significant sightings of Minke whale calves, as well as unexpected species such as the Beluga/White whale - a mainly Arctic species, and White-tailed Tropicbirds which are usually seen in the tropics.

The ObSERVE Aerial project represents the first time that the winter abundance and density of cetaceans and seabirds have been estimated in this region.  Among other achievements, the results from these new geographically extensive surveys will help to inform future assessments of species' conservation status and the risk to protected species and their habitats from human or environmental stressors.

For further information about the ObSERVE programme, please contact us at


Scientific publications from the ObSERVE Aerial project:

New insights into ocean sunfish (Mola mola) abundance and seasonal distribution in the northeast Atlantic

Using tagging data and aerial surveys to incorporate availibility bias in the abundence estimation of blue sharks (Prionace glauca)​​

Assessing the effectiveness of foraging radius models for seabird distributions using biotelemetry and survey data