by
The
two
maps
above
show
Europe’s
beaver
population
in
1900
compared
to
2021.
They
both
come
from
this
wonderful
video
by
Qarol
Mapping:
The
Eurasian
beaver
(Castor
fiber)
was
hunted
to
the
brink
of
extinction
for
its
fur
and
castoreum,
leaving
only
around
1,200
individuals
surviving
across
eight
isolated
populations
ranging
from
France
to
Mongolia
by
1900.
However,
widespread
reintroductions
across
Europe,
means
there
is
now
an
estimated
population
of
at
least
1.5
million
in
2021.
But
what’s
going
on
with
North
American
beaver
(Castor
canadensis)
population
in
Finland?
North
American
beavers
were
introduced
to
Finland
in
1937,
initially
intended
as
a
reintroduction
effort
after
the
local
extinction
of
Eurasian
beavers.
At
the
time,
it
was
not
recognized
that
the
North
American
beaver
was
a
separate
species.
From
an
initial
group
of
seven
individuals,
the
population
expanded
rapidly,
reaching
approximately
12,000
animals
within
64
years.
By
1999,
around
90%
of
Finland’s
beavers
were
identified
as
North
American.
Despite
their
introduction,
North
American
beavers
are
not
universally
viewed
as
invasive,
since
their
ecological
role
in
Europe
closely
mirrors
that
of
Eurasian
beavers,
which
have
not
returned
to
the
region
naturally.
To
manage
their
numbers,
hunting
licenses
have
been
issued.
A
2010
report
concluded
that,
although
the
current
American
beaver
population
in
Finland
poses
no
significant
ecological
issues,
their
higher
reproductive
rates
and
tendency
to
build
slightly
larger
dams
could
lead
to
problems
if
their
range
expands
eastward
into
Russia.
However,
such
an
expansion
has
not
yet
been
observed.
Below
you
can
see
the
map
for
1900
vs
2021
in
more
detail:
1900
2021
Differences
Between
the
Eurasian
and
North
American
Beaver
| Feature |
Eurasian Beaver (Castor fiber) |
North American Beaver (Castor canadensis) |
|---|---|---|
|
Size & Weight |
Slightly smaller and lighter; typically weighs 11–30 kg. |
Slightly larger and heavier; typically weighs 16–32 kg. |
| Fur |
Generally lighter-colored, grayish-brown fur. |
Darker, reddish-brown fur. |
|
Skull & Head Shape |
Longer, narrower skull with a less prominent nose. |
Shorter, wider skull with a more prominent, rounded nose. |
|
Tail Shape |
Narrower, less oval-shaped tail. |
Broader, more oval-shaped tail. |
|
Chromosome Count |
48 chromosomes. |
40 chromosomes. |
|
Dam Building |
Smaller dams and lodges. |
Larger dams and lodges. |
| Reproduction |
Smaller litter sizes (average 1–3 kits). |
Larger litter sizes (average 3–4 kits). |
|
Behavioral Traits |
More cautious and wary of humans; less adaptable to human-altered landscapes. |
More adaptable and somewhat more tolerant of human presence. |
| Range |
Native range extends from Western Europe to East Asia (historically widespread, but reduced). |
Widely distributed throughout North America (Canada, USA, Mexico). |
|
Conservation Status |
Historically near extinction but recovering in parts of Europe and Asia. |
Common and abundant, not threatened. |
What
do
you
think
of
this
map?
Go to Source
Author: Brilliant Maps
