Distribution, abundance and movements of the bottlenose dolphin in the Pelagos sanctuary MPA.

1. The Pelagos Sanctuary is the largest marine protected area of the Mediterranean Sea (87 500?km2), and is located in the north-west part of the basin. The presence of the bottlenose dolphin in this area is well documented but its distribution and abundance are not well known. 2. The present study collected and analysed data from 10 different research groups operating in the Pelagos Sanctuary from 1994 to 2007. Photo-identification data were used to analyse the displacement behaviour of the dolphins and to estimate their abundance through mark–recapture modelling. 3. Results show that the distribution of bottlenose dolphin is confined to the continental shelf within the 200?m isobath, with a preference for shallow waters of less than 100?m depth. 4. Bottlenose dolphins seem to be more densely present in the eastern part of the sanctuary and along the north-west coast of Corsica. 5.Bottlenose dolphins show a residential attitude with excursions usually within a distance of 80?km (50?km on average). A few dolphins exhibit more wide-ranging journeys, travelling up to 427?km between sub-areas. 6.The displacement analysis identified two (sub)populations of bottlenose dolphins, one centred on the eastern part of the sanctuary and the other one around the west coast of Corsica. 7. In 2006, the eastern (sub)population was estimated to comprise 510–552 individuals, while 368–429 individuals were estimated in the Corsican (sub)population. It was estimated that in total, 884–1023 bottlenose dolphins were living in the Pelagos Sanctuary MPA in the same year. 8. The designation of a number of Special Areas of Conservation (SACs) under the Habitats Directive is discussed as a possible tool to protect the bottlenose dolphin in the Pelagos Sanctuary and in the whole of the Mediterranean Sea.