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Mediterranean and Black Sea Cetacean Red List Assessment
Tursiops truncatus ponticus
There is no estimate of total population size but information from incomplete surveys suggests that the
current population size is not less than several 1000s of animals.
The past 60-year period (1946-2005; three generations) includes events, circumstances and trends that
are relevant to Criterion A, as follows:
(1) Large directed takes occurred before the ban on small cetacean hunting was declared in Turkey
in 1983. Within the 38-year period from 1946-1983, the total number of bottlenose dolphins killed was at
least 24,000-28,000 but certainly much greater (probably by tens of 1000s) because those figures do not
incorporate any catch statistics from Romania, or for Turkey before 1976 and after 1981, or for Bulgaria
before 1958 (see “Threats”). There are indications of some recent intentional killing and harassment in
Ukraine;
(2) Regionally dispersed incidental mortality in bottom-set gillnets from 1946 through the 1980s is
roughly estimated at some 100s per year. The scale of this mortality almost certainly increased in the
1990s-2000s owing to the rapid expansion of illegal, unreported and unregulated fishing in the Black Sea;
(3) Live-capture of bottlenose dolphins for captivity, including the attendant mortality during capture
operations, is roughly estimated at 1,000-2,000, all told, since the early 1960s. Live-captures continue in
the Russian Federation, with 10-20 animals taken annually from a small area;
(4) A mass stranding/mortality event of unknown cause occurred in 1990, believed to have involved at
least 100s of bottlenose dolphins;
(5) There has been ongoing degradation of the Black Sea environment overall (including bottlenose
dolphin habitat) and declines in many of its indigenous animal populations (including bottlenose dolphin
prey) from the 1970s to the present, with a likely peak in the devastation caused by overfishing and habitat
deterioration (including pollution and explosive growth of populations of invasive species) in the late
1980s–early 1990s. These processes, taken together, have led to severe declines in prey populations.
The inference of a reduction in population size of 50% was supported by a simple simulation in which
the population was assumed to increase at a constant rate of 4% per year and the direct and incidental
removals (as indicated by paragraphs (1), (2) and (3) above) were estimated realistically. This simulation
showed that a decline of more than 50% in the last three generations would be required for the current
population size to be about 15,000 bottlenose dolphins.
Distribution
Country Names
Territorial waters of
Native -
presence
confirmed
Native –
possibly
present
Visitor
Possibly Visitor
Vagrant
Possibly
vagrant
Other
Bulgaria
X
Georgia
X
Romania
X
Russia
X
Turkey
X
Ukraine
X
Annex 3: Regular Species
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