The Ionian Dolphin Project aims to ensure the conservation of two dolphin species in greek waters

Common dolphins and bottlenose dolphins are studied by means of several research techniques to understand how they interact with their environment

Dolphins inhabiting the coastal waters of Greece are facing significant threats. Some dolphin populations must deal with increasing human encroachment, while others have disappeared altogether from portions of their former range. The Ionian Dolphin Project aims to ensure the long-term viability of two dolphin species living in two coastal areas of western Greece: the Amvrakikos Gulf and the Inner Ionian Sea archipelago.

bottlenose dolphin (Tursiops truncatus)

Bottlenose dolphins (Tursiops truncatus)

The most abundant coastal cetacean species in the Mediterranean Sea have been negatively affected in numerous ways by human activities. Until the 1960s, they were one of the main targets of culling campaigns, resulting in thousands of animals killed. In recent times, incidental mortality in fishing gear, prey depletion caused by overfishing, habitat degradation, boat traffic, noise, and health effects caused by pollution are important threats. Mediterranean bottlenose dolphins have been proposed for classification as Vulnerable in a recent Red List assessment by IUCN.

Common dolphin (Delphinus delphis)

Short-beaked common dolphins (Delphinus delphis)

Once one of the most abundant cetacean species in the Mediterranean Sea, common dolphins have declined throughout the region since the 1960s. The Ionian Dolphin Project aims to understand, through long-term monitoring, how the local dolphin communities interact with their environment and how human activities – particularly fisheries and pollution – may affect their conservation status. By deploying state-of-the-art techniques, the project contributes tools to 1) inform management action, 2) promote marine conservation in Greece, and 3) support conservation efforts in the wider Mediterranean region.

In 2003 the Mediterranean population was classified as Endangered in the IUCN Red List. In 2006 they have been included in Appendix I and II of the Convention on the Conservation of Migratory Species (Bonn Convention – CMS). The causes of their decline include prey depletion by overfishing and incidental mortality in fishing gear

Research methods

  • Surveys to monitor dolphins in the study areas are conducted daily from the IDP’s rigid-hulled inflatable boat equipped with a 100HP outboard engine.

  • Individual photo-identification, used to obtain information on dolphin abundance, movements, habitat use, social organization and reproductive success.

  • Recordings of the group size and behavior of the dolphins during long-lasting observation sessions, which are subsequently analyzed through GIS software.

  • Recordings of other marine species including sea turtles, tuna, swordfish and seabirds observed during the surveys at sea.

  • Inspection of dead dolphins found stranded or adrift in the study area, to identify the causes of death whenever possible, and collection of biological samples for further investigations. Occurrence of dolphin by-catch in fishing gear is also recorded.

  • Assessment of the interactions between dolphins and local fisheries.

Example of the evolution of the dorsal fin of a bottlenose dolphin regularly observed by the IDP team in the Ionian Sea between 2004 and 2010

shapes of dorsal fins of dolphins