130925-studie-wildlife-comeback-in-europe

Executive summary
With biodiversity in continuing decline
worldwide, and targets set to reduce biodiversity
loss not being met, conservation successes are
rare in comparison to the news on declining
populations and extinctions. Wildlife in Europe
is showing a variety of responses to human
pressure: while certain groups are clearly in
decline and require conservation attention,
other wildlife species are showing resurgence
from previously low levels. Understanding the
mechanisms allowing this wildlife comeback is
crucial to better conservation of wildlife both in
Europe and across the world, if we can apply the
principles underlying conservation success to
reverse declines in other species.
In this report, we attempt to unravel patterns
and processes behind wildlife comeback in Europe
since the mid-20 th century, focussing on a selected
subset of mammals and birds. Of the many
possible metrics of biodiversity change, we focus
on two of the most useful and widely reported in
order to understand the recent positive changes
in some species. Firstly, we examine changes in
species range. Secondly, we examine the change in
population abundance and possible factors behind
the trends, such as the mitigation of threats or
targeted conservation action.
The story of conservation success against a
backdrop of a biodiversity crisis is given centre
stage by means of detailed accounts for 18
mammal and 19 bird species showing signs of
comeback. For each, we examine population
trends over time and evaluate historical and
current ranges, highlighting where a species’
range has contracted, persisted, expanded or
been recolonised over time.
Our analysis shows that while these species
have increased in abundance since the 1960s (with
the exception of the Iberian lynx (Lynx pardinus),
which declined), there is great variation between
species and regions. For example, abundance
increases ranged from less than 10% for the Red
kite (Milvus milvus) to more than 3,000% for the
European bison (Bison bonasus), Eurasian beaver
(Castor fiber), White-headed duck (Oxyura leucocephala)
and some populations of Pink-footed
goose (Anser brachyrhynchus) and Barnacle goose
(Branta leucopsis). For mammal species, increases
in abundance were greatest in southern and
western Europe.
Analysis of range change showed that the
mammal species selected for this study have, on
average, increased their distribution range by
around 30% since the mid-20 th century. Ranges
of bird species selected for this study have on
average remained stable over the same time
period, although the majority of species at first
contracted considerably, but then expanded
again by 14% since the 1980s. There is much
variation in species distribution trends among
taxa and across space, from clustering of range
expansions in Fennoscandia and eastern Europe
for mammalian carnivores, to pan-European
increases in deer, with opposing trends between
central and northwestern Europe, where more
bird species have expanded, and southeastern
Europe where more have contracted.
We find that wildlife comeback in Europe since
the mid-20 th century appears to be predominantly
due to species protection and active targeted
conservation (both birds and mammals), habitat
management and site protection (birds) and legal
protection (both). Of the species management
techniques, actively boosting existing or setting
up new populations, via translocations and
reintroductions, was the foremost type of species
management linked to increased abundances
amongst mammals and birds. Reduction in
hunting pressure, protection from persecution
and the phasing out of certain toxic chemicals,
thus decreasing non-natural mortality, were also
important for species recovery.
Despite a picture of increasing abundance and
expanding distributions for a number of European
bird and mammal species, many other species are
still at risk. Furthermore, the results of this report
have to be viewed in the context of large historical
range declines. In some instances, such as with
European carnivores and many bird species, ranges
and abundances had already declined dramatically
from historical distributions by the mid-20 th
century. Therefore, wildlife resurgence has to be
White-tailed eagle in
Flatanger, Norway.
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