In 2012 circa 28 000 grey seals were counted in the Baltic Sea.
Grey seals sighted in censuses in the 2000s throughout the Baltic Sea (red);Finnish count shown in blue.
The number of ringed seals observed during ringed seal counts has increased but slower than the number of grey seals. It is still thought that the reason for the slow growth of ringed seal population is due to a reproductive problem. According to calculations by Swedish researchers*, the ringed seal population in the Bay of Bothnia has grown approximately 4.5 per cent yearly between 1988 and 2006.
*Source: Tero Härkönen, Naturhistoriska riksmuseet
It is estimated that a little over hundred years ago there were up to 90 000 grey seals and 180 000 ringed seals in the Baltic Sea. On the other hand, the seal populations were at their most reduced level in the 1970's and 1980's when it was estimated that 2000–4000 grey seals and fewer than 5000 ringed seals remained. The main reason for the decrease in seal populations was excessive hunting. Later on after the 1960's, the reason for their population decrease can be found in high levels of toxic substances, which have weakened the breeding efficiency. Today, seal populations are recovering.
Seal-counting flights are made during the moulting period in the spring.
Photo: Petri Timonen
Baltic seals – balancing between sustainable ecosystem management and fisheries (ECOSEAL)
Hyljeseuranta (in Finnish)