Marine Mammals of Turkey: Dolphins, Porpoises, and Seals

Turkey’s marine mammal fauna includes dolphins and harbour porpoises across the Black Sea, Marmara, Aegean and eastern Mediterranean, together with the Mediterranean monk seal along suitable Aegean and Mediterranean coasts. The most consistently documented focal species are the common bottlenose dolphin, short-beaked common dolphin, striped dolphin, Risso’s dolphin, harbour porpoise and Mediterranean monk seal. Rough-toothed dolphins and several other members of the dolphin family are supported by rarer, geographically limited or recently confirmed records.

Why Published Marine Mammal Totals for Turkey Differ

An updated national checklist published in 2025 reports 12 marine mammal taxa within Turkey’s wild mammal fauna.[a] That total is not a count of dolphins, porpoises and seals alone: it also covers whales accepted by the checklist. A separate TUDAV review published in 2019 discusses 13 cetacean species reported from Turkish seas, including regular species, rare visitors and historical records.[b]

The two figures describe different bodies of evidence. The 2025 checklist applies national mammal-list criteria, whereas the 2019 marine review also discusses unusual sightings, strandings and historical reports from Turkish seas.

Dolphins, Porpoises and Seals Recorded in Turkish Waters

The checklist below separates repeatedly documented regional taxa from species known through sparse, exceptional or recently published records. In this table, “regular” refers to repeated documentation within the relevant sea area; local abundance and seasonal use still vary by place and survey period.

The Black Sea’s Three-Cetacean Assemblage

The modern Black Sea cetacean assemblage consists of the common bottlenose dolphin, short-beaked common dolphin and harbour porpoise. Regional conservation literature usually refers to the Black Sea forms as Tursiops truncatus ponticus, Delphinus delphis ponticus and Phocoena phocoena relicta. The three taxa divide the basin differently according to depth, shelf structure, prey and season.

A basin-wide aerial survey found common dolphins concentrated mainly in deeper waters during summer, including southern survey sectors crossed by transects off Turkey. Bottlenose dolphins showed a stronger association with coastal and shallow shelf habitat along parts of the western Turkish Black Sea coast. Harbour porpoises occurred in coastal and shelf waters but were also recorded offshore and over deeper Turkish waters.[c]

The aerial-survey pattern is seasonal. Sea state, survey coverage, prey movements and time of year all influence detections, while poorly sampled sectors can appear emptier than they are.

Common Bottlenose Dolphin

Bottlenose dolphins use coastal waters, bays, shelf areas and the Turkish Straits System. Their ability to forage near shore and around human-modified seascapes makes them one of the cetaceans most likely to overlap with small-scale fisheries, vessel routes and heavily used coastal zones. Black Sea animals are assessed separately from the wider Mediterranean population because the regional population is biologically and geographically distinct.

Short-Beaked Common Dolphin

Common dolphins are documented in all four Turkish sea areas, but their ecology differs among basins. In the Black Sea they often occur farther offshore than bottlenose dolphins during summer surveys. In the Aegean and Mediterranean, records include coastal and open-water settings, and regional conservation assessments distinguish the inner Mediterranean subpopulation from the Black Sea population.

Black Sea Harbour Porpoise

The harbour porpoise is the only porpoise regularly documented in Turkish waters. Its main Turkish range lies in the Black Sea, Bosphorus and Marmara. Records farther into the Aegean are unusual, with the core Turkish occurrence concentrated in the Black Sea, Bosphorus and Marmara. The species’ small body size, brief surfacing behaviour and limited visibility in rough water also make visual detection more difficult than for many dolphins.

Marmara and the Turkish Straits Connect Two Marine Faunas

The Bosphorus, Sea of Marmara and Dardanelles form a narrow marine connection between the Black Sea and Aegean. Bottlenose dolphins, common dolphins and harbour porpoises are all documented in this system. Animals observed in the straits may be feeding locally, moving between adjacent areas or using only part of the connected corridor.

Marmara records also include occasional taxa that are more characteristic of deeper Aegean or Mediterranean habitat. Risso’s dolphin, for example, appears in Marmara mainly through occasional sightings or strandings. Such records fit the sea’s role as a narrow transition between neighbouring cetacean communities rather than the pattern seen in its three regularly documented small cetaceans.

Aegean and Eastern Mediterranean Dolphin Diversity

The Aegean and eastern Mediterranean support a broader dolphin assemblage than the Black Sea. Bottlenose and common dolphins use coastal and shelf waters, while striped and Risso’s dolphins are more strongly associated with open water, continental slopes, deep basins and submarine canyon systems. Offshore surveys have also produced records of rough-toothed dolphins and other rarely encountered delphinids.

Striped Dolphin

Striped dolphins are regular in the Aegean and Mediterranean but are not part of the Black Sea cetacean fauna. Their offshore habitat reduces the number of casual land-based observations, so survey routes, ferry observations, acoustic monitoring and strandings all contribute to the regional record. In Marmara, the species is represented by occasional records rather than the repeated pattern seen in the Aegean and Mediterranean.

Risso’s Dolphin

Risso’s dolphins are associated mainly with deeper Aegean and Mediterranean waters. They can approach land where steep coastal slopes bring deep water close to shore, while their main habitat remains associated with deeper water. Their distribution is linked partly to deep-diving cephalopod prey and the structure of continental slopes and canyons.

Mediterranean Monk Seals Depend on Undisturbed Coastal Refuges

The Mediterranean monk seal is not a cetacean. It is a true seal in the family Phocidae and must return to land for resting, giving birth and nursing. In the eastern Mediterranean, suitable habitat includes remote rocky shores, sea caves and, historically, open beaches. Marine caves now provide many of the least disturbed resting and pupping sites available to the species.[i]

Turkey’s Aegean and Mediterranean coasts contain breeding and resting habitat, but occupancy is highly uneven. Seal use is concentrated in caves and rocky refuges with suitable entrances, internal beaches or ledges, manageable wave exposure and limited disturbance from people and fishing activity.

Regional conservation planning calls for the protection and management of monk seal caves, haul-out sites and pupping areas along the Turkish Aegean and Mediterranean. Recommended measures include regulating human entry, reducing disturbance around occupied sites and protecting the surrounding marine area rather than treating only the cave chamber as habitat.[j]

Rare Delphinids Recorded in Turkish Waters

Several animals with “whale” in their English names are taxonomically dolphins. False killer whales and pilot whales belong to Delphinidae, the same family as bottlenose, common and striped dolphins. Their larger body size does not place them among the baleen whales or sperm whales.

Rough-Toothed Dolphin

A published encounter provided the first confirmed documentation of rough-toothed dolphins in the eastern Mediterranean waters of Turkey.[f] ACCOBAMS reporting also records the species during expanded Turkish visual and acoustic survey work. Current records remain concentrated in the eastern Mediterranean and do not yet define the size or continuity of a Turkish population.

False Killer Whale

A group of false killer whales was observed approximately six nautical miles from Gökçeada on 21 January 2020. The record was reported as the first sighting for the northern Aegean Sea.[g] It adds the northern Aegean to the documented regional occurrence record, while repeated use around Gökçeada has not been established.

Long-Finned Pilot Whale

Long-finned pilot whales appear in historical and regional lists for the Aegean and eastern Mediterranean, where they are treated as rare. Turkish evidence consists of occasional or historical records rather than a repeatedly documented coastal population.

The Mersin Bay Humpback Dolphin Record

Two to four humpback dolphins were reported from Mersin Bay during observations in February and April 2016, and the publication identified them as Indian Ocean humpback dolphins, Sousa plumbea.[h] The underlying visual material has also been described as sufficient for identification to the genus Sousa but not necessarily for an uncontested species-level determination. The record remains an exceptional Turkish occurrence, with the genus-level identification and the published Sousa plumbea determination both relevant to its interpretation.

Conservation Status Depends on the Assessed Population

A species can receive different Red List categories at global, Mediterranean and Black Sea scales. The unit being assessed may be an entire species, a named subspecies or a regional subpopulation. Black Sea, Mediterranean and global assessments therefore need to be matched to the population unit named in each assessment.

The table records categories published through an ACCOBAMS resolution compiling assessments completed from 2018 to 2021.[d] Several Black Sea entries were presented as provisional submissions awaiting completion of the IUCN review process. Later ACCOBAMS reporting stated that updated assessments for the three Black Sea cetaceans were under review, so the table retains the assessment scale and publication context beside each category.[k]

A Red List category describes extinction risk for a defined assessment unit. Local abundance, detectability and trends in Turkish waters require separate field data.

Bycatch Is the Clearest Measured Pressure in the Black Sea

Entanglement in fishing gear is one of the most direct causes of human-related cetacean mortality documented in the Black Sea. Harbour porpoises are particularly exposed because their habitat overlaps with fixed nets and other coastal fisheries. A recent ACCOBAMS scientific assessment reported that estimated Black Sea harbour porpoise bycatch exceeded the modelled sustainability threshold used in the analysis.[e]

Observed carcasses capture only part of bycatch mortality because some animals sink, decompose offshore, are removed from gear without being reported or strand beyond monitored coastlines. Stranding records also include deaths from other causes. Bycatch assessment therefore combines carcass examination, fishing-effort data, onboard or electronic observation and uncertainty estimates.

What Western Black Sea Strandings Reveal

A TUDAV compilation recorded 1,243 cetacean strandings along the western Turkish Black Sea coast between 2003 and 2016. Harbour porpoises accounted for 77 percent, bottlenose dolphins 10 percent, common dolphins 7 percent and unidentified cetaceans 6 percent. The 77 percent figure describes the recovered stranding sample along the monitored coast; living-community composition requires abundance surveys rather than carcass proportions.

Underwater Noise, Vessel Traffic and Coastal Disturbance

Cetaceans rely on sound for orientation, communication and foraging. Shipping, seismic exploration, construction, military sonar and other intense sound sources can mask biological signals or alter behaviour. ACCOBAMS reporting identifies oil and gas activity and military operations as underwater-noise concerns along the Turkish Mediterranean coast, with monitoring and mitigation treated as research and management priorities.

The Turkish Straits carry dense commercial vessel traffic through habitat used by dolphins and porpoises. Risk is not limited to direct collision. Repeated vessel approaches, propeller noise and disruption of feeding groups may affect how animals use narrow passages. The degree of effect depends on vessel type, speed, distance, repetition and the behaviour of the animals at the time.

For monk seals, disturbance occurs at the boundary between sea and land. Coastal construction, cave entry, boat anchoring near resting sites, deliberate harassment and fishing activity around cave approaches can reduce access to the quiet refuges needed for pupping and nursing. Protection restricted to the dry part of a cave does not address disturbance in the water immediately outside it.

Fishing Interactions Are Not All the Same

• Incidental capture: an animal becomes entangled or trapped in gear set for another species.
• Depredation: dolphins remove catch from fishing gear, sometimes damaging nets and increasing the chance of retaliation or entanglement.
• Prey competition: fishing and marine mammals use overlapping fish resources, although the scale and direction of competition must be tested rather than assumed.
• Gear modification: changes in net design, setting depth, soak time, season or fishing area may reduce capture risk when supported by trials and monitoring.
• Acoustic deterrents: devices may reduce some interactions but can also exclude animals from habitat or lose effectiveness, so deployment requires species- and fishery-specific assessment.

What Sightings, Strandings and Surveys Reveal

Research cruises, citizen observations, ferry routes, stranding programmes and first-record papers describe different parts of Turkey’s marine mammal record. Designed surveys estimate animals available for detection along defined transects, stranding programmes document carcasses found on monitored shores, and first-record papers add unusual occurrences to the known fauna.

Well-watched bays can produce dense record clusters simply because they receive more observation effort. The same individual may also appear on multiple days. Photo-identification reduces duplication by matching dorsal-fin markings, while line-transect surveys use detection models to account for animals missed by observers.

Acoustic monitoring adds records for vocal species during darkness or poor weather, with detection distance influenced by call type, depth, equipment and background noise. Monk seal work uses another set of methods, including cave cameras, track or scat evidence, direct observation and genetic sampling. Together, these approaches describe occurrence, habitat use and population structure at different spatial scales.

Recent Turkish programmes have expanded visual and acoustic work in the eastern Mediterranean, while Black Sea assessments continue to update distribution, bycatch and population-status evidence. The eastern Mediterranean remains unevenly surveyed, particularly across offshore and deep-water habitat, and additional survey coverage can fill large gaps in the present occurrence record.[l]

ACCOBAMS entered 2026 with two developments relevant to Turkish marine-mammal research: the CetaBankTR cetacean tissue-bank project was reported as completed, and ASI-II continued preparations for coordinated Mediterranean aerial, vessel and passive-acoustic survey work through 2028.[m][n]

Sources and Verification

1. [a] An updated checklist of the wild mammals of Türkiye — 2025 national checklist reporting 177 wild mammals, including 12 marine taxa.
2. [b] Cetacean Studies in Turkey — Turkish-seas review covering historical records, occurrence classes, fisheries and western Black Sea strandings.
3. [c] CeNoBS Black Sea Cetacean Survey Report — Basin-wide summer aerial-survey results for Black Sea bottlenose dolphins, common dolphins and harbour porpoises.
4. [d] ACCOBAMS Resolution 8.12 on Red List Assessments of Cetaceans — ACCOBAMS resolution compiling dated Black Sea and Mediterranean population-level Red List assessments.
5. [e] Report of the ACCOBAMS Scientific Committee — Scientific Committee report covering Turkish survey work, Black Sea harbour porpoise bycatch and underwater-noise priorities.
6. [f] First documentation of rough-toothed dolphins in the eastern Mediterranean Sea of Türkiye — First confirmed record of Steno bredanensis in the eastern Mediterranean waters of Türkiye.
7. [g] First record of false killer whales in the northern Aegean Sea — Report of the 21 January 2020 false killer whale sighting near Gökçeada.
8. [h] Occurrence of humpback dolphins in Mersin Bay — Publication describing the February and April 2016 humpback dolphin observations in Mersin Bay.
9. [i] IUCN Mediterranean Monk Seal Conservation Handbook — IUCN handbook on Mediterranean monk seal monitoring, resting and pupping habitat, and conservation work.
10. [j] Regional Strategy for the Conservation of the Mediterranean Monk Seal — Regional monk seal strategy covering caves, haul-out sites and pupping habitat along Turkish Aegean and Mediterranean coasts.
11. [k] Report on the Conservation Status of Cetaceans and Relevant Activities in the Black Sea — Black Sea report on cetacean assessment updates, monitoring, bycatch and regional conservation activity.
12. [l] Report on the Conservation Status of Cetaceans and Relevant Activities in the Eastern Mediterranean — Eastern Mediterranean report summarizing survey coverage, research activity and offshore data gaps.
13. [m] ACCOBAMS — Establishing a Cetacean Tissue Bank in Türkiye (CetaBankTR) — 2026 Scientific Committee document reporting the completed national cetacean tissue-bank project.
14. [n] ACCOBAMS Survey Initiative II — Current programme information for the 2025–2028 regional survey initiative and its 2026 Mediterranean campaign.