Between 2001 and 2009 151 bottlenose dolphins (Tursiops truncatus) were identified based on long-term natural marks on their dorsal fins. Density of dolphins in the Amvrakikos Gulf is among the highest recorded anywhere in the Mediterranean Sea. However, this is not indicative of favourable conservation status or pristine habitat. Dolphins in this virtually closed ecosystem constitute a geographically and otherwise distinct conservation unit with little demographic exchange and by living in this semi-closed shallow habitat, face a high risk of extinction due to their reproductive isolation, small population size and small extent of occurrence, as well as to acute and growing anthropogenic impacts.
In 2010, after two years of no recorded sightings a group of short-beaked common dolphins (Delphinus delphis) in the Inner Ionian Sea Archipelago was spotted. The group was composed of twelve individuals: 9 adults, 1 juvenile and 2 calves. 5 of the adults were recognized from previous years and scientists propose that they have been absent due to depletion of local fish-stocks resulting from overfishing.
For the first time since beginning work in the Gulf ‘emigration’ of bottlenose dolphins has been detected from Amvrakikos Gulf to the Inner Ionian Sea archipelago and in the Gulf of Corinth. These observations show that even animals appearing to be resident within a given area (i.e. the Amvrakikos Gulf) can temporarily leave “home” and range over large portions of sea.
In 2010 had the project had its first ever sighting of the striped dolphins Stenella coeruleoalba.
The abundance of dolphins in the Gulf is largely due to local abundance of their prey and is not an indication of a pristine environment or low anthropogenic impact. Eutrophication (an increase in the concentration of chemical nutrients in an ecosystem to an extent that increases the primary productivity of the ecosystem) and pollution have been increasing in recent years and the resulting threats are not mitigated or even addressed by management action. This is curious, considering the inclusion of the whole Amvrakikos Gulf in a National Park, the inclusion of northern sectors of the Gulf in the Natura 2000 network (EC Sites of Community Importance) and designations as Ramsar site (wetlands of international importance designated under the Ramsar Convention) (1975), Special Protection Area (EC Directive 79/409 on the conservation of wild birds), and Specially Protected Area (SPA, under Protocol 4 of the Barcelona Convention).
The project has developed strong relationships with the local community in the city of Vonitsa, where the field station is based, through engaging local fishermen and school children. Events such as ‘dolphin days’ to teach children about dolphins and conservation, beach-cleaning, dolphin lectures, meetings, and the distribution of educational booklets have all helped to gain local support in the area.
Marine and Freshwater Ecosystems, 18(2): 130-146
Bearzi, G., Agazzi, S., Gonzalvo, J., Costa, M., Bonizzoni, S., Politi, E., Piroddi, C. & Reeves, R.R. (2008) Overfishing and the disappearance of short-beaked common dolphins from western Greece. Endangered Species Research, 5: 1-12
Bearzi, G., Fortuna, C.M., Reeves, R.R. (2009) Ecology and conservation of common bottlenose dolphins Tursiops truncatus in the Mediterranean Sea. Mammal Review, 39(2): 92-123
Gonzalvo J. (2007). Marine conservation as a common goal: the benefits of communication between marine biologists and artisanal fishermen. Pp. 15-16 In: D. Maldini, D. Meck Maher, D. Troppoli, M. Studer, J. Goebel (Eds.) Translating scientific results into conservation actions: new roles, challenges and solutions for 21st Century scientists. Earthwatch Institute, Maynard MA, USA.