A grey seal (Halichoerus grypus), representative of the North Atlantic species, has been recorded in the north-east Black Sea. It is the first documented case of successful long-term survival of an exotic pinniped. We have been receiving data about regular sightings of the seal identified as the observed individual since 2001. It is a 160–170 cm long adult female. The seal used an underwater cave as a shelter. The most likely way of introduction of the grey seal to the Black Sea is escape from captivity. According to available data (body size and moulting seasonality), we tentatively identify it as a representative of the Baltic subspecies. The biotope requirements of the grey seal and monk seal are similar: both species use coastal karst caves and grottos. In addition, the seal's presence in this region is a marker of the lack of anthropogenic disturbance. Thus, the survival of a seal in this region indicates the possibility of successful re-colonization of the Black Sea by monk seals.

The Mediterranean monk seal is categorized as Critically Endangered on the IUCN Red List and is in urgent need of effective conservation measures. Following a steep decline in the 20th century, the National Park Service of Madeira initiated efforts to protect the species in the archipelago of Madeira, including habitat protection, scientific research and public awareness. The aim of this study was to analyse data collected during a monitoring project (1988–2005) to assess the conservation status of the species and identify priority conservation actions for the future. The study recorded the presence of the species at key pupping sites in a strictly protected area at the Desertas Islands, increased sightings in recent years around the main island of Madeira, an increase in the number of pups born, and low mortality. The population in the archipelago of Madeira is currently estimated to be 20-30 adults. These findings suggest that the species remains Critically Endangered in the area but that its conservation situation has improved because of the implementation of effective conservation actions. Conservation priorities identified include protecting suitable monk seal habitat at Madeira, investigating seal–fisheries interactions, increasing environmental education, and strengthening regional legislation for the protection of the species.