130925-studie-wildlife-comeback-in-europe

Figure 1a.
Distribution of
Alpine ibex in
Europe in 1800 [4] ,
1967 [16] and 2008 [2] .
Please note that the
1967 distribution
represents an
over-estimation of
the species’ actual
range.
Figure 1b.
Map highlighting
areas of range
expansion,
persistence and
contraction of the
Alpine ibex in Europe
between 1967 and
2008. Please note
that contraction
observed from 1967
to 2008 is likely to
be an artefact of the
difference in map
resolution.
Drivers of recovery
There are several possible reasons for the increases
in population size observed from our data set of
Alpine ibex (Table 3). At a country level, populations
from Italy and Switzerland, which have
shown range change since the mid-20 th century
(Figure 1a), are increasing at a low rate at just
above zero. In contrast, an ibex population from
France was associated with the largest increase in
abundance over the study period. This population
resulted from a reintroduction to the Vercors
area in the Western Alps [17] , and its increase was
considered in support of a reintroduction project
of the Bearded vulture (Gypaetus barbatus)
here. Unexpectedly, populations that were not
threatened and did receive management intervention
increased less than their counterparts. It is
possible that the lack of information available from
the French population skewed the results, and that
this population may well have been managed in
some way and not affected by any threats.
Other possible factors influencing the change
in population of the Alpine ibex can be identified
from the literature. For example, the Gran Paradiso
population is strongly affected by winter conditions,
with low snow depth in mild winters in
the 1980s resulting in an increase due to adult
survival, and this may have also positively affected
recruitment [7] . In general, yearly fluctuations in
numbers were negatively affected by population
density, by winter snow depth, and by the inter-
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