130925-studie-wildlife-comeback-in-europe

Threat Description Impact
Hunting and Hunting, trapping and egg collection.
High
trapping
Unintentional
effects of hunting
and trapping
Natural systems
modification
Transport and
service corridors
Renewable
energy
Table 2.
Major threats that
drove Whooper swan
decline and may
still constrain the
population [1, 4, 47] .
Table 3.
Conservation actions
in place for Whooper
swan [1, 4, 7, 52, 53] .
Action
Legislation
Site/area
protection
Secondary poisoning from ingestion of lead
pellets.
Drainage of wetland habitats.
Collision with overhead power cables.
Planned wind power plant developments are
likely to be an important cause of habitat loss for
Icelandic Whooper swans.
Medium
Historically high
Medium
Potentially high
the 1840s [25] , but the species’ distribution in the
country contracted 1,100km northwards [16] . Since
the 1950s, Whooper swans have been extending
their distribution southwards in Norway, Sweden,
Finland, and Russia, and have recently become
established as a breeding bird in the Baltic States,
Poland, Germany, Denmark, the Netherlands,
Hungary, Belarus and Ukraine [5, 6, 26–44] (Figure 2),
while first breeding in France was recorded in
2012 [45] and a small number breed in the UK [46] . In
contrast, the winter distribution has not changed
appreciably [8] , although there are some indications
of a southward shift in Britain and Ireland [7] .
Description
Legally protected across its range and listed in various international
treaties (see ‘Legal protection and conservation status’).
There are 737 identified IBAs for Whooper swan in Europe, of which
61% are designated as SPAs or other protected areas and 9% are not
protected.
Most key wintering areas and many key breeding areas of the
northwest European population are protected, but few foraging
areas lie in protected areas.
Few key sites for the Icelandic population are protected.
Major threats
Unsustainable hunting, trapping and egg
collection were the main driver of the decline
in Whooper swans in Europe during the 19 th and
early 20 th centuries [48, 49] . Persecution drove the
northwest European population northwards into
poor quality habitat and unsuitable arctic climate,
which resulted in declines in reproductive performance
[4, 50] . Habitat loss through the drainage of
wetlands is also likely to have had an adverse effect
on Whooper swan population size [1, 6] . As the species
switched to foraging in agricultural habitats, a
conflict with agriculture has developed due to the
damage caused to crops and pasture, which is the
main ongoing threat to the species [7] .
Other threats include lead poisoning from the
ingestion of lead shot, collision with powerlines,
and the risk posed by development of wind power
plants in the UK [1, 51] .
Drivers of recovery
The most important driver of the recovery of the
species following the declines suffered prior to
the 1950s is the protection of the species from
hunting [1, 7] . Improvements in food availability
during the winter, through the expansion and
intensification of agriculture contributed to
increase and range expansion of Whooper swans
in northwest Europe [54] . Breeding in the Baltics
also means that Whooper swans overwinter closer
to their breeding grounds, resulting in a shorter
migration [55] , while milder winters have also been
very beneficial to Whooper swan productivity [6] .
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