Cetaceans in the coastal waters of southern Romania: initial assessment of abundance, distribution, and seasonal trends

Cetaceans in the coastal waters of southern Romania: initial assessment of abundance, distribution, and seasonal trends

Romulus-Marian Paiu, Bogdan Olariu, Angelica-Ioela Paiu, Mihaela-Elena Mirea Cândea, Anca-Maria Gheorghe, Dumitru Murariu

Mare Nostrum NGO, Bogdan Voda Street 16, Constanta, 900613, ROMANIA
Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, Bucharest, R-050095, ROMANIA
Faculty of Geography, University of Bucharest, 1st Nicolae Balcescu blvd., Bucharest 010041, ROMANIA


This paper presents the results of two vessel surveys in 2017 (spring and summer) in order to estimate cetacean abundance and distribution in Romanian Black Sea waters following distance sampling methods. Eight transects, from east to west, perpendicular on the shore line with a total length of 211.95 km, were designed and executed in sea conditions ≤ Beaufort 4 in an area of 1063 km2with coverage of 39.6%. In total there were 275 sightings of bottlenose dolphin (Tursiops truncatus ponticus), common dolphin (Delphinus delphis ponticus) and harbour porpoise (Phocoena phocoena relicta) recorded. Both European Union (EU) Marine Strategy Framework Directive and Habitats Directive require Member States to monitor and maintain at favourable conservation status those species identified to be in need of protection, including all cetaceans. This study provides the baseline data on the Black Sea cetaceans in Romanian waters.

Keywords: Black Sea, cetaceans, abundance, distribution, line transect sampling, vessel survey

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