Newsletter / Blog
2012-07-15 Sea Ducks in rough water - Europe
The 2012 IUCN Red
List for birds released by BirdLife International gave a strong warning message
that the risk of extinction has increased substantially for nearly 100 species
of Amazonian birds. What are the results for Europe?
Detailed surveys
in the Baltic Sea for the period 2007-2009 revealed that almost 3 million Long-tailed Ducks - Clangula hyemalis - have disappeared
from the Baltic Sea since the previous survey
in 1992-1993. This sharp decline in numbers resulted in the species being
uplisted to Vulnerable.
The Steller’s Eider - Polysticta stelleri - was already listed as Vulnerable but
decreased also by 66% in the Baltic Sea, while
the fortunes of another sea duck, Velvet
Scoter - Melanitta fusca are even
worse, with the species now being listed as Endangered.
Overall, the
numbers of sea duck species wintering in the Baltic Sea
have declined by about 60%. As these sea ducks feed on bivalves (like mussels,
clams and oysters, whose populations are also declining and changing in size and
distribution), ecosystem changes and global warming are plausible causes.
Factors as
predation, diseases and nutritional deficiencies are also present. But the
direct threats identified are caused by human activities, eg degradation of the
seafloor life caused by fishing as well as oil pollution, by catch in
fisheries, hunting and pollution by hazardous chemicals. Not all of these
factors are the ultimate reason for the decline but their cumulative effect and
the fact that they can be contained by targeted management and legislation
makes them important for consideration. |