ESTONIAN ENVIRONMENTAL REVIEW 2009

8.4.2. Species: seals
With the mild winters of recent years, the status of the
two seal species in Estonian waters, the grey and ringed
seal, has come under attention. The grey seal primarily
inhabits coastal areas adjacent to open sea and rocks that
just barely protrude over sea level. Expeditions in search
of food are often long and they catch food at a depth of
50–100 m. The use of feeding areas varies seasonally; in
autumn the creatures prefer shallower areas closer to
the coast. They prefer ice floats for giving birth, but in
the absence of such ice they are capable of giving birth
on dry land. The abundance of grey seals has risen in the
last decade in Estonian coastal areas and throughout the
Baltic Sea. This is a case of a population that inhabits the
entire Baltic Sea and which grows about 7–8% a year in
their native habitat in the central part of the Sea. The
Baltic grey seal is currently no longer threatened.
The ringed seal’s habitat is in the straits where they
mainly spend night hours on the rocks lining the islands’
coasts. They head for deeper water in summer to search
for food, at a depth of 30–80 metres. Ringed seals are
more stationary than grey seals and their primary habitat
in Estonia is in the Väinameri straits and the Gulf of Riga.
When ice forms on the Väinameri, they usually head to
the northern part of the Gulf of Riga and the Bay of Pärnu,
where their primary reproduction areas are located. Their
reproductive success depends completely on the existence
of ice and how long it lasts. In the last five years,
only 2003 and 2006 have seen solid ice cover, while the
rest of the winters have been warmer than the average.
In 2008, reproduction was completely unsuccessful as
the ice was nearly lacking. The abundance of ringed seals
in Estonia is not known exactly but it is not estimated to
exceed 1500 animals. The Estonian population is detached
from other populations in the Baltic Sea and no migration
takes place. The ringed seal is an endangered species in
Estonia, and the population’s status may worsen given
the frequent mild winters.
5000
4000
4127
number of individuals
3000
2000
1000
0
1567
1611
1893
2206
2548
2826
2781
2390
3010
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Figure 8.17. Grey seal abundance in 1999–2008. Data: Environmental Board.
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