Cetaceans in Greece: Present status of knowledge

2008b). No information is available from the Aegean Sea and the Gulf of Corinth. However,
the habitat and behaviour of the few short-beaked common dolphins that live in mixed pods
with striped dolphins in the Gulf of Corinth indicate that a diet primarily based on
cephalopods is likely.
Main threats
The threats most likely implicated in the decline of Mediterranean short-beaked common
dolphins are diverse and include prey depletion, contamination by xenobiotics, direct killing,
fishery bycatch and global climate change (Bearzi et al. 2003). However, the long-term study
of the inner Ionian population unit suggested that the most important threat is prey depletion
caused by overfishing (Bearzi et al. 2008b). Unsustainable fisheries exploitation resulting in
food-web and other damage are an ongoing and possibly increasing threat for this and other
cetacean species in Greek waters. Overfishing has caused a continuing decline of the fish
stock biomass in the Greek Seas since the mid 90s (Stergiou 2005, Stergiou et al. 2007),
including the short-beaked common dolphin’s key prey (Machias et al. 2007). According to
the available information, it seems that two more threats for this species in Greece are
related to interactions with fisheries. A short-beaked common dolphin was found stranded
with trammel nets around its head and lower jaws. Two more specimens that stranded in the
N Aegean had marks probably originating from nets and a third one was found stranded with
its flukes cut off by a knife. At least once, two or three short-beaked common dolphins were
found stranded the same day in the Thracian Sea. This evidence indicates that bycatch and
possibly direct killing occur and constitute a threat. Direct, intentional killing by some
fishermen would not be a surprise, since it occurs for common bottlenose dolphins and
striped dolphins and most fishermen do not discriminate among dolphin species.
IUCN Red List classification
Mediterranean subpopulation classified as ‘Endangered’ (Bearzi 2003); listed as ‘Least
Concern’ globally (IUCN 2008).
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