130925-studie-wildlife-comeback-in-europe

Estimate Year assessed Reference
Global >1,036,226 2012
[11]
Europe (minimum) >337,539 2003–12
[6, 12–18]
% of global population 33%
Austria >3,000 2008
[12]
Belarus 24,000 2003
[6]
Belgium 200–250 2003
[6]
Bosnia and Herzegovina Unknown - -
Croatia 180 2003
[6]
Czech Republic 500 2003
[6]
Denmark 188 2011
[13]
Estonia 11,000 2003
[6]
Finland 2,000 2003
[6]
France 14,000 2011
[14]
Germany >25000 2013
[12]
Hungary 500 2007
[15]
Latvia >100,000 2003
[6]
Lithuania 50,000–70,000 2003
[6]
Netherlands 507 2010
[16]
Norway 70,000 2003
[6]
Poland 18,000–23,000 2003
[6]
Romania >170 2003
[6]
Russia (European) Unknown - -
Serbia 30 2003
[6]
Slovakia >500 2003
[6]
Spain 18 2003
[6]
Sweden >100,000 2003
[6]
Switzerland 1,600 2007/8
[17]
Ukraine 6,000 2003
[6]
United Kingdom 146 2012
[18]
1845 (which was only effective from 1899), numbers
recovered to 7,000 in 1919; however, subsequent
over-hunting caused population declines despite
reintroductions in the 1920s [5] . In the early 1940s,
individuals immigrated to eastern Norway from
the reintroduced Swedish population along the
Trysil watershed [5] . This natural spread continued,
becoming a significant factor in the 1970s, and
this, in combination with reintroductions in the
1950s and 1960s in Norway, led to considerable
increases in number and range, leaving the species
to occupy the country in two disjunct populations
(Figure 1a) [5] .
Hunted to extinction in 1938, Lithuania provides
ideal habitat for the Eurasian beaver [5] . Reintroductions
between 1947 and 1959, coupled with
immigration from Latvia, Belarus and Kaliningrad
in Russia, has led to a constant increase since the
end of the 1940s [5] . Even though range expansion
halted in the mid-1970s, when the beaver occupied
the entire country [5] , increases have continued in
the late 1990s due to the post-Soviet abandonment
of drained farmland leading to scrub regrowth,
which combined with existing drainage ditches
provide ideal beaver habitat [2] .
Abundance and distribution: changes
Table 2.
Latest population
estimates for the
Eurasian beaver
globally, in Europe
and for European
populations. Please
note that there
was no information
available for Bosnia
and Herzegovina, and
European Russia.
is currently found throughout Latvia except the
northwestern part [5] .
The beaver occurs in all of Sweden except the
south, northwest, and the area around Uppsala
north of Stockholm, and this population forms
part of the continuous distribution of the species
from the Baltic to the Atlantic [5] . The population,
which was extirpated in 1871 [6] , was re-established
entirely through reintroductions [2] . Following
reintroductions of Norwegian beavers from
1922 at 19 sites, the species was able to expand
reasonably quickly due to limited barriers
resulting from the topological characteristics of
the country [5] . After rapid range extension, the
characteristic population explosion took place in
the 1970s, resulting in an estimated population
of over 100,000 individuals spread across what
is now a continuous range [5] . Populations are
completely protected in the northernmost
province Norrbotten, in the eastern Uppsala and
Stockholm provinces, and in the south, while
seasonal unrestricted hunting elsewhere results in
an annual harvest of around 6% per annum [5] .
Growing from a remnant population of around
100 individuals [5] , the Norwegian beaver has
provided source stock for all Scandinavian populations
and now represents up to 21% of the species
in Europe (Table 2). After receiving protection in
In 1955, the Eurasian beaver occurred in over 25
distinct populations in eastern Germany, the south
of France, eastern Europe and Scandinavia (Figure 1a),
occupying an area of over 256,000 km 2 . By 2013, the
range had increased by 650% to nearly 1,670,000
km 2 , adding territory across the European continent
(Figures 1a and b). While the species seemingly lost
ground in the south of France, eastern Germany,
Norway, northern Sweden and Ukraine, this is likely
to be an artefact of the difference in map resolution.
The 1955 map is very simplified, giving the impression
that the beaver has contracted compared to the more
detailed 2013 range. However, it is possible that even
the present day map, although broadly accurate,
represents an underestimate of distribution due
to the rapidly changing situation of the species
across the continent [1] , which would lead to greater
expansion since 1955 than depicted in Figure 1b.
Range loss may, however, be a reality in Finland,
where the beaver is experiencing interspecific
competition with the introduced North American
beaver (Castor canadensis) [1] . Despite this, previously
disjunct populations have been connected, creating
large ranges in central and eastern Europe, and in
Norway and Sweden, and creating new populations
in countries where the species had been absent for
many centuries, for example Spain and the United
Kingdom (Figures 1a and b).
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