ABSTRACT
Historically, products from seals have provided an important extra income for people inhabiting the Swedish coast (Almkvist et al., 1980). Thus seals have been the subject of intense hunting. Furthermore, seals were regarded as vermin by fishermen, and bounties were paid for killing seals between 1808 and 1864, and again from 1891 to 1974. After the Second World War the number of seals was low because of this intensive hunting. Despite decreased hunting pressure after the war, the Swedish seal populations did not recover (Bergman, 1956). The populations of all three species of seals which inhabit the Baltic, the grey seal (Halichoerus grypus), the ringed seal (Pusa hispida botnica) and the harbour seal (Phoca vitulina), were found to further decrease rapidly in the 1960s and 1970s (Almkvist et al., 1980). According to a recent report (Hårding and Härkönen, 1999), the grey seal population in the Baltic Sea decreased from 88 000-100 000 at the beginning of the twentieth century to approximately 4000 in the late 1970s. The corresponding decrease for the ringed seal in the Baltic Sea during the same period was from 190 000220 000 to approximately 5000. The harbour seal population in the Baltic Sea at the beginning of the twentieth century was about 5000 (Hårding and Härkönen, 1999). At present, the Baltic harbour seal population is estimated at 600 (Helander and Härkönen, 1999). From the beginning of the 1980s a slight increase in seal populations has been recorded in the Baltic Sea. Based on photo-ID data the number of Baltic grey seals recently is estimated to be about 12 000 (Hiby et al., 2001). Low numbers of ringed seals have been recorded in the Baltic Sea: 200-300 in the Gulf of Finland and 1400 in the Gulf of Riga (Härkönen et al., 1998).
