Sinop IMMA

Sinop IMMA map

Size in Square Kilometres

755 km2

Qualifying Species and Criteria

Black Sea Harbour Porpoise – Phocoena phocoena relicta

Criterion A, B(2), C(2)

Black Sea Bottlenose dolphin – Tursiops truncatus ponticus

Criterion A, B(2), C(2)

Black Sea Common dolphin – Delphinus delphinus ponticus

Criterion A, B(2), C(2)

Marine Mammal Diversity 

Phocoena phocoena relicta, Tursiops truncatus ponticus, Delphinus delphinus ponticus

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Sinop Region is home to three cetacean subspecies — harbour porpoise, bottlenose dolphin and common dolphin. Black Sea subspecies of harbour porpoise and bottlenose dolphin are listed as endangered while Black Sea common dolphin is listed as vulnerable species in the IUCN Red List. The boundaries of the Sinop IMMA are delimited to the 200-meter depth contour around the peninsula. There is some evidence that there might also be high densities of common dolphins and harbour porpoises much further offshore all round the peninsula however the IMMA is limited to coastal waters around the peninsula which is thought to be one of the main wintering areas for harbour porpoises. Estimated population densities of harbour porpoises, bottlenose dolphins and common dolphins increase considerably in the spring season. Such agglomerations in the spring, which is the breeding period of those species, coincide with the turbot fishing period using bottom gillnets (both legal and illegal), which are the main cause of the bycatch cases, and this make the region more critical for the conservation of the cetaceans. Furthermore, observations of stranded newborn harbour porpoises are an indication that Sinop Region supports might be suitable area to harbour porpoises for calving.

Description of Qualifying Criteria

Criterion A – Species or Population Vulnerability

The Black Sea subspecies of harbour porpoise Phocoena phocoena relicta and bottlenose dolphin Tursiops truncatus ponticus are listed as Endangered (EN), and common dolphin Delphinus delphis ponticus as Vulnerable (VU) on the IUCN Red list (Birkun & Frantzis, 2008; Birkun 2008b; Birkun, 2012).

Criterion B: Distribution and Abundance

Sub-criterion B2: Aggregations

Although the harbour porpoises tend to form small groups from one to ten individuals in the Black Sea, they can be seen aggregated into hundreds of individuals in fish-abundant regions along their paths of seasonal migration (Birkun, 2008a). Such accumulations, the group size of which reaches 150 individuals, were observed during the winter in the Sinop IMMA.  The area is known as a wintering ground for anchovy, and is also one of the wintering grounds for harbour porpoise. Estimated density for harbour porpoise in the Sinop IMMA is 1.86 ind/km² (CV: 20.43%; 95% CI: 1.22-2.82) in winter (Özsandıkçı, 2021).  In the spring season, there is a considerable increase in the estimated density of both harbour porpoises and bottlenose dolphins. According to the results of line transect surveys, density estimates were 3.14 ind/km2 (CV: 29.96%; 95% CI: 1.76-5.62) for harbour porpoise, 0.44 ind/km2 (CV: 24.55%; 95% CI: 0.27-0.72) for bottlenose dolphin and 1.06 ind/km2 for common dolphins in the spring season (Özsandıkçı, 2021). There is a considerable increase in densities for all three species in spring compared to other seasons (Özsandıkçı, 2021) (Figures 4,5,6). In another boat-based survey, harbour porpoise sightings were clustered in the Sinop region and adjacent waters (Tonay, A.M., 2006, unpublished data) (Figure 7). Increased numbers of bycaught harbour porpoise in bottom turbot gillnets also implies spring aggregation of this species in the area (Gönener and Bilgin, 2009). Recently, harbour porpoise and common dolphin observations were recorded on the transect passing by Sinop Region, in the basin-wide aerial surveys within the CeNoBs Project (Paiu et al, 2021, in prep.).  The boundaries of the IMMA area are limited to a 200-meter depth contour around the peninsula. The results of the recent basin wide aerial surveys conducted within CeNoBS project in the summer of 2019 summer indicate high densities of common dolphins and harbour porpoises much further offshore all round the peninsula. On the other hand, the results of another boat-based line transect study carried out in shallow waters in four seasons show clearer evidences for the Sinop area’s importance and geographical range so that the IMMA has been limited to the coastal waters.

Criterion C: Key Life Cycle Activities

Sub-criterion C2: Feeding Areas

The Sinop IMMA is an area of intense fishing activity including both artisanal and industrial boats. The area is also well known as an overwintering area of the anchovy (Chashchin, 1996) which is the main prey species of the harbour porpoise. Evidence that harbour porpoises use the Sinop Region as a wintering ground is related mostly with overwintering anchovy schools in the area. All three cetacean species have been observed with clear feeding behaviour (associated with sea gulls, foraging behind trawlers) in the recent boat-based surveys (Özsandıkçı, 2021). In addition, anchovy stocks in the north Black Sea coast migrate directly to the mid-south Black Sea coast at the beginning of December and form dense schools when the water temperature drops suddenly due to the influence of strong northerly winds (Gucu et al. 2017). Besides, since it is a peninsula elongated to the north, it is an intersection point of the migration routes of pelagic fish moving between east and west. The fact that European sprat, Sprattus sprattus, which is another main prey fish of cetaceans in the Black Sea, migrates to the coastal regions of the south-central Black Sea during spring (Daskalov et al. 2012) may also be related to the cetacean density in this region.

Supporting Information

Bat, L., Erdem, Y., Ustao, S. ve Sat, H. H. 2005. A Study on the Fishes of the Central Black Sea Coast of Turkey, 16.

Birkun, A. A. (2008a). The state of cetacean populations. In T. Oğuz (Ed.), State of the Environment of the Black Sea (2001–2006/7) (Vol. 3, pp. 365–399). Publications of the Commission on the Protection of the Black Sea Against Pollution (BSC) 2008-3.

Birkun, A. A. (2008b). Delphinus delphis ssp. ponticus: Birkun Jr., A.A: The IUCN Red List of Threatened Species 2008: e.T133729A3875256 [Data set]. International Union for Conservation of Nature.

Birkun, A. A. (2012). Tursiops truncatus ssp. ponticus: Birkun, A.: The IUCN Red List of Threatened Species 2012: e.T133714A17771698 [Data set]. International Union for Conservation of Nature.

Birkun, A. A., & Frantzis, A. (2008). Phocoena phocoena ssp. relicta: Birkun Jr., A.A. & Frantzis, A.: The IUCN Red List of Threatened Species 2008: e.T17030A6737111 [Data set]. International Union for Conservation of Nature.

Birkun, A. A., Northridge, S., Willsteed, E., James, F., Kilgour, C., Lander, M., & Fitzgerald, G. (2014). Adverse fisheries impacts on cetacean populations in the Black Sea (Final report to the European Commission). European Comission.

Chashchin, A. K. (1996). The Black Sea populations of anchovy. Scientia Marina, 60, 219–225.

Çelikkale, M. S., Karacam, H., Düzgünes, E., Ünsal, S., & Durukanoglu, H. F. (1989). Size and distribution of dolphin populations in the Black Sea. Turkish. J. Zool, 13, 189-196.

Daskalov G, Cardinale M, Charef A et al. (2012) Scientific, Technical and Economic Committee for Fisheries. Assessment of Black Sea Stocks (STECF-12-15). Publications Office of the European Union, Luxembourg.

Gladilina, E. V., Lyashenko, Yu. N. ve Gol’din, P. E. 2013. Winter Distribution of Cetaceans in the Black Sea and Adjoining Areas in 2012/2013. Scientific Notes of Taurida V.I. Vernadsky National University Series: Biology, chemistry, Biology, chemistry, 26(65), 37-42.

Gönener, S. & Bilgin, S. 2009. The Effect of Pingers on Harbour Porpoise, Phocoena phocoena Bycatch and Fishing Effort in the Turbot Gill Net Fishery in the Turkish Black Sea Coast. Turkish Journal of Fisheries and Aquatic Sciences, 9(2). doi:10.4194/trjfas.2009.0205

Gücü, A. C., Genç, Y., Dağtekin, M., Sakınan, S., Ak, O., Ok, M., & Aydın, İ. (2017). On Black Sea anchovy and its fishery. Reviews in Fisheries Science & Aquaculture, 25(3), 230-244.

Key Biodiversity Areas Partnership (2020). Key Biodiversity Areas factsheet: Sinop Peninsula. Extracted from the World Database of Key Biodiversity Areas. Developed by the Key Biodiversity Areas Partnership: BirdLife International, IUCN, American Bird Conservancy, Amphibian Survival Alliance, Conservation International, Critical Ecosystem Partnership Fund, Global Environment Facility, Global Wildlife Conservation, NatureServe, Rainforest Trust, Royal Society for the Protection of Birds, World Wildlife Fund and Wildlife Conservation Society. Downloaded from on 26/02/2021.

Kırkım, F., Özcan, T., Sezgin, M., Çulha, M., & Katağan, T. (2014). Marine isopods (Crustacea) of Sinop Bay (Black Sea, Turkey). Journal of the Black Sea/Mediterranean Environment, 20(3).

Oğuz, T., Latun, V. S., Latif, M. A., Vladimirov, V. V., Sur, H. I., Markov, A. A., … Ünlüata, Ü. (1993). Circulation in the surface and intermediate layers of the Black Sea. Deep Sea Research Part I: Oceanographic Research Papers, 40(8), 1597-1612. doi:10.1016/0967-0637(93)90018-X

Özdemir, S., Erdem, Y., Özsandıkçı, U., & Büyükdeveci, F. (2017). Incidental catch problem of common porpoise (Phocena phocena) in the Black Sea Coastal Fisheries. International Symposium on Ecology and Enviromental Problems, Çanakkale, Turkey.

Özsandıkçı, U. (2021). Estimating Cetacean Abundance and Distribution in Sinop Coasts of the Black Sea. (Thesis no: 668565) [Doctoral Dissertation, Sinop University].

Özsandıkçı, U., Tonay, A. M., Danyer, E. ve Dede, A. (2019). Cetacean stranding records on the central Turkish Black Sea coast in May 2017- April 2019 (s. 484). World Marine Mammal Conference, Barcelona.

Özsandikçi, U., & Gönener, S. (2020). Effectiveness of Pingers on the Harbour Porpoise Phocoena phocoena relicta Abel, 1905 (Cetacea: Phocoenidae) in Turkey as Revealed by Shore-based Observations. ACTA ZOOLOGICA BULGARICA, 72(1), 155-159.

Paiu, M., Panigada, S., Cañadas, A., Gol`din, P., Popov, D., David, L., Roul, M., Belmont, J., Ozturk, A.A. (2021). Part A Detailed Report on cetacean populations distribution and abundance in the Black Sea CeNoBS/ACCOBAMS Survey Initiative. Constanta. (in prep.)

Tonay, A.M. (2006, unpublished data) Cetacean sighting survey in western and central coasts of the Turkish Black Sea in the spring 2016.

Ürkmez, D., Sezgin, M., Karaçuha, M. E., Öksüz, İ., Katağan, T., Bat, L., … & Şahin, F. (2016). Within-year spatio-temporal variation in meiofaunal abundance and community structure, Sinop Bay, the Southern Black Sea. Oceanological & Hydrobiological Studies, 45(1).


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