Status of grey seals along mainland Europe from the Southwestern Baltic to France

Abstract

<div>The grey seal was a common species along mainland Europe during the Stone Age (8,000-5,500 BC). Along the North Sea coast populations started to decline substantially during the 11th century as a result of excessive hunting. The last breeding populations disappeared in the 16th century in the Wadden Sea, and before 1900 in the Kattegat-Skagerrak and the Southwestern Baltic as a result of an extermination campaign. No regular pupping occurred along mainland Europe until the end of the 1970s, when a breeding colony was established near Amrum in the German Wadden Sea. Somewhat later, additional breeding sites were discovered near Terschelling in the Dutch Wadden Sea (1980), at Helgoland, and off Brittany in France. Tracking of movements indicate these seal groups to be linked to the larger populations in the UK. Numbers of grey seals in the recolonised areas have increased over the years, but in the Kattegat-Skagerrak stable numbers</div><div>of about 25 individuals have been observed since the 1970s, whereas more than 100 grey seals are found in the Southwestern Baltic. In the southeastern North Sea, 120 grey seals occur during moult at Helgoland, 120 in the German and over 1,130 in the Dutch parts of the Wadden Sea in 2004. Along the southern Dutch and Belgian coasts small groups are regularly observed, but no colonies have yet been established. In the colonies off Brittany in France about 105 grey seals have been counted. Successful pupping has only been recorded 3 times in the Kattegat-Skagerrak over the past 30 years, and 2-4 pups are born annually in France and the Southwestern Baltic. The relative strongholds for breeding along the European continent are the Dutch Wadden Sea, where in 2003/2004 at least 150 pups were recorded, Amrum in the German Wadden Sea (23 pups) and Helgoland (8 pups). Consequently, total numbers of counted grey seals from the Southwestern Baltic to France amounted to at least 1,600 in 2004, while about 190 pups were born in the area.</div

The 1988 and 2002 phocine distemper virus epidemics in European harbour seals

“…In the Kattegat they disappeared before 1900, and the present low numbers originate from both the northeast Atlantic and the Baltic (Søndergaard et al 1976, Härkönen et al 2006. Grey seals equipped with satellite transmitters showed highly migratory behaviours (Dietz et al 2003, S. Brasseur & P. Reijnders unpubl.…”

Status of Baltic grey seals: Population assessment and extinction risk

“…Thus, vital rates cannot be transferred from other populations uncritically. On the other hand, the Baltic grey seal has most likely been isolated from other North-East Atlantic grey seal populations for less than 9,000 years (Härkönen et al 2007) and they share many basic biological features with other grey seal populations. Our approach has been to utilize data from other grey seal as a 'best guess' and adjust values when information from the Baltic was available.…”

“…Hunting caused regional extinctions of grey seals in France, the Wadden Sea, the Kattegat-Skagerrak, the Limfjord, the southern Baltic (Härkönen et al 2007), and the US Atlantic coast (Barlow et al 1995). After protective measures were undertaken in the mid 20th century, some of these regions have been re-colonised since the 1970s.…”

“…After protective measures were undertaken in the mid 20th century, some of these regions have been re-colonised since the 1970s. However, reproducing grey seal populations are still absent from several regions where they were abundant only 2 centuries ago (Härkönen et al 2007). Thus, experience tells us that grey seals are vulnerable to hunting pressure and great care should be taken if hunting is introduced.…”

State of biodiversity in the Nordic countries

“…For example, the number of harbour seal (Phoca vitulina) in Sweden and Denmark has increased by more than 500% in 30 years (Figure 9.5). Also, in recent years the grey seal (Halichoerus grypus) has slowly started to recover after its near-extinction in the Nordic region about 100 years ago (Härkönen et al 2007). The positive trends are mainly due to bans on seal hunting and protection of breeding sites.…”