North Aegean Sea - Key Species
Anchovy (Engraulis encrasicolus)
Anchovy is the most abundant fish species in the ecosystem and in the landings, and is mainly caught by purse-seiners. It is a short-lived species (the majority of individuals caught are 1-2 years old) with interannual biomass fluctuations, it feeds on mesozooplankton and spawns during summer. Anchovy was identified as the fish species with the larger overall effect in the N. Aegean Sea ecosystem. It is considered fully exploited.
Sardine (Sardina pilchardus)
Sardine and anchovy comprise 30% of Greek landings. Sardine spawns mostly during winter and mainly feeds on mesozooplankton. Sardine catch peaked during the late 1980s and has shown a decreasing trend since with high interannual fluctuations. It is considered fully exploited.
European hake (Merluccius merluccius)
Hake mainly feeds on large invertebrates and fish, including small pelagics. It is also a cannibalistic species. Hake is one of the main commercial species; small individuals are mainly fished with trawls and nets, while the larger ones are fished with longlines. It is considered over-exploited.
Red mullet (Mullus barbatus)
It is a lower trophic level species, which mainly feeds on benthic invertebrates and detritus. It is one of the main target species for bottom trawls and artisanal fleets.
Invasive Ctenophore (Mnemiopsis leidyi)
This invasive ctenophore has entered the N. Aegean Sea in the 1990s. It was considered responsible, together with overfishing, for the collapse of the small pelagic fishery in the Black Sea (Daskalov 2002). Even though the impact on the N. Aegean Sea food-web is not yet considered very high, its recent spread in other parts of the Mediterranean and the population blooms that it presents, suggest that its impact might increase, which is the cause of some concern.
Marine birds
Several species of seabirds are present in the area some of which are considered vulnerable. The more common species are Larus cachinnans (Yellow-legged gull), L. melanocephalus (Mediterranean gull), L. audouinii (Audouins gull, near threatened according to IUCN Red List), Calonectris diomedea (Corys shearwater), Puffinus yelkouan (Yelkouan shearwater, near threatened) and Phalacrocorax aristotelis (Shag). Most of the gulls mainly feed on fishery discards, the shearwaters forage in open waters, while the shag is restricted in coastal areas.
Dolphins
Tursiops truncatus (bottlenose dolphin) and Delphinus delphis (common dolphin) are mainly found in the shallow parts of the area, while Stenella coeruleoalba (stripped dolphin) is occasionally found in deeper waters. A very small population of Phocaena phocaena (harbour purpoise) is also present in the area. Information about population status in the area is unfortunately scarce for all cetacean species. Although by-catch of dolphins and harbour porpoise is low, they are highly impacted by the fisheries due to their low turnover rates.
Mediterranean Monk Seal (Monachus monachus)
The Mediterranean monk seal is one of the most endangered mammals in Europe (listed as critically endangered in the IUCN red list). Few individuals are dispersed in rocky islands in the area. Conservation action for this species is mainly focused on hotspots in Greek Seas.