12 March 2009

Amvrakikos Gulf: new photo-identification data

The research project ‘Dolphins of Greece’, conducted by Tethys in the Amvrakikos Gulf, has recently completed the analysis of photo-identification data pertinent to the whole 2008.

A total of 3,818 selected digital photos, obtained from January to December during sightings along survey transects that cover the whole gulf, allowed to photo-identify 115 individual bottlenose dolphins.

Most of these recognizable individuals are well-known and were already present in the catalogue started in 2001 , but four of them are new animals never seen before.

Ten of the 115 dolphins were sighted together with immature individuals (newborns, calves or juveniles) and this looks like a promising sign for this highly-resident population that lives in a semi-closed eutrophic gulf.

Photographs included a number of non-identifiable animals, i.e. individuals carrying no distinctive marks on their dorsal fins. These, as well as all the subadult classes, should be added to the number of animals sighted in 2008. So, at present, it appears that the total number of animals seen in the Gulf last year is consistent with the population estimate of 150 made in previous years (Bearzi et al. 2008).

Ongoing monitoring will allow researchers to gain insight into the ecology and trends of this unique bottlenose dolphin community.

Silvia Bonizzoni

For more information:
Bearzi G., Agazzi S., Bonizzoni S., Costa M., Azzellino A. 2008. Dolphins in a bottle: abundance, residency patterns and conservation of bottlenose dolphins Tursiops truncatus in the semi-closed eutrophic Amvrakikos Gulf, Greece. Aquatic Conservation: Marine and Freshwater Ecosystems 18(2):130-146.


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