130925-studie-wildlife-comeback-in-europe

5. Overview of wildlife comeback
In this section we synthesise the information
gathered in the species accounts to ask what this
information can tell us about the resurgence
of selected species in Europe, in terms of the
magnitude of change in abundance and distribution
and the predominant reasons underlying
the comeback of these species. This will help us to
apply lessons learned to other species across Europe
in order to stem the tide of biodiversity loss, meet
conservation targets and ultimately allow the re-establishment
of a wilder Europe for all to enjoy.
Changes in population size
The species presented in this study were selected on
the basis of a notion that they had all undergone a
recovery after a period of serious decline. As a result,
it is not surprising that all the bird and mammal
species [with the exception of the Iberian lynx (Lynx
pardinus), for which the data showed declines in
abundance although recently the species has been
showing signs of steep recovery from its all-time
low] showed increases in abundance from the
mid-20 th century to the present. However, there
was high variability among species (Figures 1 and 2).
This is due in part to the variation in rate of increase
across the study period, but also to the regional
variation within species trends.
most of the species with complete time series
showed overall increases since 1961, recovery of the
Northern chamois and Harbour seal was evident
from 1965 and 1977 respectively. It is important
to note that time series are not complete for all
of our species (see Figure 3), and that the number
of populations for which data were available also
varied over time.
Regional patterns in abundance change show
a complex picture when grouped across species
(Figure 5). Eastern Europe, which has been the
source for many of the comeback species [e.g. the
Grey wolf (Canis lupus) and the Eurasian lynx (Lynx
lynx)], exhibited the lowest increases in abundance,
while southern and western regions in particular
experienced on average the highest increases in
population abundance across mammal species.
This is likely to reflect growth in abundance at the
range margins of several species.
Variation in abundance change was largest in
western Europe which is most likely a reflection of
varying success of range expansion and population
establishment in areas where wildlife had previously
been decimated.
It is important to remember that since 2005
there have been further increases for some species
and populations, although much of this data was
not yet available for our analysis (but see recent
development sections in the species accounts).
Mammals
For mammals, the greatest abundance increases
over the period from 1960 to 2005 were observed
in herbivores, specifically in the European bison
(Bison bonasus) and the Eurasian beaver (Castor
fiber), and the vast majority of recent trends
greatly exceed the Palearctic vertebrate average
(Figure 1). Brown bear (Ursus arctos), Harbour seal
(Phoca vitulina) and Northern chamois (Rupicapra
rupicapra) show the smallest increase, which is
comparable to the Palearctic vertebrate average. In
terms of average annual growth rates, the Eurasian
beaver (Castor fiber) again shows the highest rates,
followed by the European bison (Bison bonasus),
although with much variability between years, and
the Grey seal (Halichoerus grypus) (Figure 3). While
Birds
For birds, the majority of species or populations
increased by between two and seven times, but
others ranged from less than 10% for Red kite
(Milvus milvus), to more than 70 times for the
Svalbard population of Barnacle goose (Branta
leucopsis) and more than 40 times for the Russian/
Baltic population of that species, more than 40
times for the Iceland/Greenland population of
Pink-footed goose (Anser brachyrhynchus) and
more than 30 times for White-headed duck (Oxyura
leucocephala) (Figure 2).
Much of this variability was due to differences
among bird species in the realised yearly growth
rates, as well as the year at which recovery began.
On average, species recovered by 5% per year from
Grey seal at Donna
Nook in England,
an RAF bombing
range where
decades without
persecutionhave left
the seals now being
very relaxed in the
presence of humans.
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