07.04.2021 | 2. Biodiversity of the Proposed IMMA of the Turkish Straits System

FESCH.TV INFORMIERT:

Liam van Walsum, Enorha Guimard, Tim Awbery, Belen Yıldırım, Aylin Akkaya

The Turkish Straits System (TSS) is an important waterway that serves as a trade artery for a large part of Central and Eastern Europe, holds strategic importance as a gateway for world navies and is historically considered the divide between Europe and Asia. However, the system is also important as it hosts a diverse array of marine mammals and was recently proposed as an IMMA because of this diversity.

The system itself consists of the Istanbul Strait (Bosphorus), Sea of Marmara and the Canakkale Strait, and connects the Black Sea to the Mediterranean via the Aegean Sea. The Black and Aegean seas have a distinct salinity gradient and therefore the Sea of Marmara behaves as an acclimatisation water body for organisms travelling through the strait.

The TSS hosts two marine mammal assemblages: The Black Sea assemblage consisting of genetically distinct subspecies of Bottlenose dolphins (Tursiops truncatus ponticus), Short Beaked Common dolphins (Delphinus delphis ponticus), and Harbour porpoise (Phocoena phocoena relicta); and the Mediterranean assemblage of Bottlenose dolphins (Tursiops truncatus), Short Beaked Common dolphins (Delphinus delphis), and Mediterranean Monk seals (Monachus monachus). Species from both assemblages have been sighted within the Sea of Marmara but the extent to which species interact and mix has not been definitively determined.

The organisms that reside and travel within the TSS are subject to immense human pressures such as noise pollution, ship strikes, oil pollution, plastic pollution, entanglement, bycatch and light pollution. The extent to which these pressures impact these organisms is also not definitively known but may shed light on how cetaceans may adapt to human development.