Cetaceans in Greece: Present status of knowledge

Distribution and effort
The distribution of all available records (Figure 3, Annex II) provides a reasonably good
coverage of the Greek Seas and therefore, the geographic range given for each species is
thought to represent a good approximation of the real figures. Nevertheless, much more
effort is needed in order to obtain the precise distribution of each species. The absence of
sightings in some geographical areas is in most cases the result of lack of survey effort (e.g
the central and eastern Aegean). However, in some particular areas (Patraikos Gulf and
inner Ionian Sea) the absence of sightings more accurately reflects the scarcity of cetacean
presence. Figure 2 in Annex I provides the distribution of the searching effort so far and it is
particularly useful in avoiding misinterpretation of the results of this report, as well as for
planning future research effort.
The cetacean species recorded in the Greek Seas can be divided in three major categories
according to their distribution: a) the striped dolphin, the common bottlenose dolphin, the
sperm whale and the Cuvier’s beaked whale are or seem to be present in the entire range of
the bathymetry/habitat that is considered typical for them, b) the short-beaked common
dolphin, the fin whale and the harbour porpoise present heterogeneous distributions within
their potential habitats, c) the Risso’s dolphin can be predictably found in a small number of
areas only, although its occurrence (as sightings or strandings) has been recorded in most
geographical areas of the Greek Seas.
Stranding data
Eleven species have been identified within the stranding record (Table 1). The percentage
of identified animals among 1352 strandings from 1991 to 2008 was 47%. As the vast
majority (99%) of unidentified animals belonged almost exclusively to three delphinid
species (common bottlenose dolphins, striped dolphins and short-beaked common
dolphins), their percentages among identified animals are underestimated. Extrapolated
numbers for these three species (see methods in section “Stranding data”) for the period
1996-2008 are presented in Table 1. The common bottlenose dolphin is the most common
species among strandings (44.8%) followed by the striped dolphin (31.2%). Averages of ca.
34 and 23 stranded animals per year were recorded for these two dolphin species,
respectively. The short-beaked common dolphin was found among strandings with an
average rate of 9 stranded animals per year (11.7%). The occurrence of Cuvier’s beaked
whale (5.5%) in the stranding record accounted for about four animals per year, but when
atypical mass strandings were excluded this number was about two per year. The Risso’s
dolphin (2.2%), the sperm whale (1.7%) and the harbour porpoise (1.5%) accounted for
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