Kaliakra to Danube Delta IMMA

Kaliakra to Danube Delta IMMA map

Size in Square Kilometres

15 445 km2

Qualifying Species and Criteria

Black Sea bottlenose dolphinTursiops truncatus ponticus

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

Black Sea harbour porpoisePhocoena phocoena relicta

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

Marine Mammal Diversity 

Phocoena phocoena relicta, Delphinus delphis ponticus, Tursiops truncatus ponticus

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Kaliakra to Danube Delta IMMA is located in the coastal and shelf waters of Ukraine, Romania and Bulgaria, extending from Hyrlo Prorva in the Ukraine in the north to Cape Kaliakra in Bulgaria in the south. It includes water depths between 1m, in the West, up to the 60 meters isobath in the east of Bulgaria, Ukrainian and Romanian waters. The IMMA area includes three EBSA regions, Danube Delta Marine Area, Kaliakra, and Vama Veche – 2 Mai Marine Reserve. The area is selected as an IMMA because in summer time it supports aggregations of two endangered species of Black Sea cetaceans: the Black Sea bottlenose dolphin Tursiops truncatus ponticus and the Black Sea harbour porpoise Phocoena phocoena relicta. There are several local sub-populations of bottlenose dolphins in the area present over several years and showing residency patterns. The coastal waters of the IMMA, including those in front of the Danube delta and the Kaliakra Cape, are an important feeding habitat for Black Sea cetaceans.

Description of Qualifying Criteria

Criterion A – Species or Population Vulnerability

The IMMA contains important habitat for the survival and recovery for all three Black Sea cetaceans species. Moreover, all the three Black Sea sub-species are included in the IUCN Red List: Black Sea bottlenose dolphin and harbour porpoise are considered Endangered, whereas the Black Sea common dolphin is considered Vulnerable. Evidence for the presence of all three species is collected from regular vessel surveys in territorial waters (Popov, 2017-2020; Paiu et al., 2019a, b, 2020a, b; Goldin et al., 2017) and two large scale aerial surveys (Birkun et al., 2014; Paiu et al., 2021). Studies of stranding events have shown the presence of the species along the coast of the area (Vasiliu, F., Dima, L., 1990; Gladilina et al, 2020, 2021;  Paiu et al., 2019b; 2020a, b; Panayotova et al., 2017)

Criterion B: Distribution and Abundance

Sub-criterion B2: Aggregations

Two large-scale studies, one conducted by Birkun in 2013, and the other one, the CeNoBS Survey in 2019, both recorded aggregations of each species within the IMMA area.  Among them, the largest aggregations of the Black Sea bottlenose dolphins in the western Black Sea were found near the Constanta coast and the Kaliakra Cape (Paiu et al., 2021), and several very high density areas for harbour porpoises were recorded within the IMMA in the vicinity of the Danube delta (Birkun et al., 2014).

During the ANEMONE surveys which were conducted in 2019 and 2020 and covered all four seasons, aggregations of all three cetacean species were observed in the territorial waters of Romania, in the marine zone of the Danube Delta, as well as near Constanta harbour and 2 Mai-Vama Veche Marine Reserve (Paiu et al., 2019; 2021). In another study conducted by the National Institute for Marine Research and Development ”Grigore Antipa” in the same areas, aggregations of each of the three species, including groups of up to 50 individuals were recorded (Nicolae et al. 2017).  In Ukrainian waters east and north-east to the Danube Delta there are regularly observed aggregations of harbour porpoises and bottlenose dolphins, mostly reported during the summer season (Birkun et al., 2014; Gol’din et al., 2017; Gladilina, 2018). Another habitat where aggregations of all the three Black Sea cetacean species are seen is the area adjacent the Zmiinij Island; their groups were recorded during all the aerial and vessel surveys in that area. Particularly large aggregations of harbour porpoises were recorded during the July 2013 vessel surveys (Birkun et al., 2014).

Ten vessel surveys conducted in Bulgarian territorial waters during the period 2017-2020 have revealed that mean encounter rate for Black Sea harbour porpoise and bottlenose dolphin is higher in the IMMA, than in the rest of the territorial waters (Popov, 2017, 2018, 2019, 2020). That gradient in density is used for defining the southern boundary of the IMMA.

In the northernmost part of the area, in Ukrainian waters, there is a local population of bottlenose dolphins seen at least during the summer, possibly of several hundred individuals. Among them, there are 35 animals individually photo-identified in 2019, and one individual was recorded in 2017 and 2019 in the same area (Gladilina et al., 2020). In the territorial waters of Romania, in the Danube Delta Marine Protected area groups of harbour porpoises and bottlenose dolphins feeding and traveling in the same area were observed from summer to late autumn. Because of the influence of the Danube River, the turbidity in the area is very high which offers good habitat for harbour porpoises (Nicolae et al., 2017). Bottlenose dolphins can be regularly encountered between Cape Midia and Constanta Harbour and in the south around Kaliakra (Nicolae et al., 2017; Paiu et al., 2021; Popov, 2019; 2020; Panayotova 2015 a, b).

Criterion C: Key Life Cycle Activities

Sub-criterion C2: Feeding Areas

Within the IMMA the presence of two species (harbour porpoise and bottlenose dolphin) is often associated with the period of migration, spawning and feeding of food resources such as horse mackerel (Trachurus mediterraneus), turbot (Scophthalmus maeoticus), European sprat (Sprattus sprattus), Black Sea herring (Alosa immaculata), whiting (Merlangius merlangus), and European anchovy (Engraulis encrasicolus) (Smederevac-Lalic et al. 2018; Yankova, 2011). The highest density of harbour porpoises was detected in spring time, and coincided with animals congregating into larger groups. Similar observations were documented in offshore waters in late autumn (Popov, 2019).  Higher abundance of bottlenose dolphins was detected in summer and autumn and relates well with seasonal fish migration into the area, and there are numerous anecdotal evidences for bottlenose dolphins and harbour porpoises feeding in front of the Danube delta (Popov, 2020; Gol’din et al., 2017).

In the IMMA feeding behavior has been observed in all three cetacean species. During all seasons bottlenose dolphins and harbour porpoises have been recorded feeding in shallow waters (Mare Nostrum Monitoring Program Report). In the southern part of the IMMA the high abundance of pelagic (anchovy, sprat, horse mackerel) and demersal (red mullet, whiting) fish species is confirmed by existing permanent fishing gear – pound nets – and regularly documented presence of porpoises and bottlenose dolphins around that gear. Interaction with regularly operating trawlers is well documented for bottlenose dolphins. Larger groups of feeding porpoises (more than 10) have also been observed at the site (Popov, unpublished).

Supporting Information

Birkun Jr., A., Krivokhizhin, S., Komakhidze, A., Mukhametov, L., Shpak, O., Goradze, I., Komakhidze, G., Kryukova, A. 2006. Wintering concentrations of Black Sea cetaceans off the Crimean and Caucasian coasts. 20th Annual Conference of the European Cetacean Society. (Gdynia, 2-7 April 2006).

Birkun Jr., A. 2008. Delphinus delphis ssp. ponticus. The IUCN Red List of Threatened Species 2008: e.T133729A3875256. https://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T133729A3875256.en. Downloaded on 24 February 2021.

Birkun Jr., A. 2012. Tursiops truncatus ssp. ponticus. The IUCN Red List of Threatened Species 2012: e.T133714A17771698. https://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T133714A17771698.en. Downloaded on 24 February 2021.

Birkun Jr., A., Frantzis, A. 2008. Phocoena phocoena ssp. relicta. The IUCN Red List of Threatened Species 2008:e.T17030A6737111. https://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T17030A6737111.en. Downloaded on 24 February 2021.

Birkun Jr., A., Willsteed, E.A., James, F.A., Kilgour, C., Lander, M., Fitzgerald, G.D, N. S. P. 2014. Studies for carrying out the common fisheries policy: adverse fisheries impact on cetacean populations in the Black Sea. European Commission. 347p.

Galtsoff, P.S. 1924. Seasonal migrations of mackerel in the Black Sea. Ecology, Vol. 5, No. 1 (Jan., 1924), pp. 1-5.

Gladilina, E., Vishnyakova, K., Ivanchikova, J., Neprokin, O., Gol’din, P. 2020. National Monitoring Survey NMS Ukraine – Cetaceans. 2020. EU-UNDP Project ‘Improving Environmental Monitoring in the Black Sea – Selected Measures (EMBLAS-Plus). Ukrainian Scientific Centre of Ecology of the Sea, Odesa.

Gladilina, E., Vishnyakova, K., Ivanchikova, Ju., Neprokin, O. and Gol’din, P. 2020. EU-UNDP Project – Improving Environmental Monitoring in the Black Sea – Selected Measures (EMBLAS-Plus). Cetaceans (Photo-ID). Data downloaded from OBIS-SEAMAP (http://seamap.env.duke.edu/dataset/2129) Downloaded on 25 February 2021.

Gol’din, P., Gladilina, E., Savenko, O., Vishnyakova, K., Neprokin, O. and Ivchenko, Ye. 2017. Identification and initial assessment of cetacean groupings in coastal waters of the north-western Black Sea, Ukrainian sector (final report). MoU ACCOBAMS N° 09/2016/FAC, 100 p.

Mazlum, R.E., Bilgin., S. 2014. Age, growth, reproduction and diet of the whiting, Merlangius merlangus euxinus (Nordmann, 1840), in the southeastern Black Sea. Cah. Biol. Mar. (2014) 55: 463-474.

Micu, D., Zaharia, T., Todorova, V., Nita, V., 2007. Romanian marine habitats of European interest. NIMRD, Contantza. 2007, p1-32.

Nicolae, C., Filimon, A., Nenciu, M., Pogurschi, E. 2017. Study on conservation status of marine mammals in the Danube Delta Marine Zone (ROSCI0066).

Paiu, M. 2019. Cetacean sightings by boat 2010-2019. Data downloaded from OBIS-SEAMAP (http://seamap.env.duke.edu/dataset/832) on 25.02.2021.

Paiu, R.M., Olariu, B., Paiu, A.I., Mirea Candea, M.E., Gheorghe, A. M., Murariu, D., 2019a. Cetaceans in the coastal waters of southern Romania: initial assessment of abundance, distribution, and seasonal trends. Journal of Black Sea / Mediterranean Environment. 25(3): 266–279.

Paiu, R-M., Mirea Candea, M., Timofe, C., Paiu, A., Gheorghe, A-M. 2019b, Raport Programul Monitorizarea şi Conservarea Cetaceelor din Marea Neagră, ONG Mare Nostrum, Constanţa.

Paiu, R-M., Mirea Candea, M., Timofe, C., Paiu, A., Gheorghe, A-M. 2020, Raport Programul Monitorizarea şi Conservarea Cetaceelor din Marea Neagră, ONG Mare Nostrum, Constanţa.

Paiu, R.M., Timofte, C., Gheroghe, A-M., Mirea-Candea, M., Tonay, A., M. 2020b. AT 4.3 Case study on cetacean stranding and sighting survey Report. ANEMONE Project. Mare Nostrum NGO. Constanta. p1-52.

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

Panayotova, M., Bekova, R., Prodanov, B. Assessment of marine cetacean populations in Bulgarian Black Sea in 2017 according to indicators of the EU Marine Strategy Framework Directive. Ecologia Balkanica, Special Edition 3, 73-83 (in press).

Panayotova, M., Todorova, V. 2015. Distribution of three cetacean species along the Bulgarian black Sea coast in 2006-2013. Journal of the Black Sea / Mediterranean Environment, vol. 21, No 1: 45-53.

Panayotova, M., Todorova, V. 2015b. Using opportunistic sightings to assess the distribution of small cetaceans in Bulgarian waters of the Black Sea in 2012. 2015. Acta Zoologica Bulgarica 67 (3): 421-427.

Popov, D., 30.10.2017. Cetacean distribution and abundance in Bulgarian territorial sea of the Black Sea, Final report, OceanCare Collaboration contract 31.01.2017, 15 pages.

Popov, D., 30.11.2018. Cetacean distribution and abundance in Bulgarian territorial sea of the Black Sea, Final report, OceanCare Collaboration contract 19.12.2017, 19 pages.

Popov, D., 30.10.2019. Cetacean distribution and abundance in Bulgarian territorial sea of the Black Sea, Final report, OceanCare Collaboration contract 07.01.2019, 22 pages.

Popov, D., 15.10.2020. “Cetacean distribution and abundance in Bulgarian territorial sea of the Black Sea”, Final report, OceanCare Collaboration contract of 25.02.20, 21 pages.

Radu, G., Nicolaev, S., Anton, E., Yankova, M., Panayotova, M., Raykov., V., 2010. Sprat and turbot fisheris in the Bulgarian and Romanian Black Sea area.

Shulman, G.E., 2002. Anchovies of the Sea of Azov and the Black Sea: Regularities of wintering migrations (Brief review).

Smederevac-Lalic, M., Kalauzi, A., Regner, S., Navodaru, I., Višnjić-Jeftić, Ž., Gačić, Z., Lenhardt, M., 2018. Analysis and forecast of Pontic shad (Alosa immaculata) catch in the Danube River. Iranian Journal of Fisheries Sciences. DOI: 10.22092/IJFS.2018.116611. 17(3) 443-457.

Vasiliu, F., Dima, L., 1990. Quelques considerations sur la presence et la mortalite des dauphins sur le littoral Roumain de la mer Noire. Pp. 171-176 in: Recherches marines (Proc. Romanian Marine Research Institute). IRCM, Constantza, 23, 200 p.

Yankova, M. 2011. An overview of the distribution of horse mackerel Trachurus mediterraneus in the Black Sea. ISSN 1314- 3379.


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