Species: Balearic shearwater (Puffinus mauretanicus)
Status: Critically Endangered (CR)
Interesting Fact: Like other shearwaters, the Balearic shearwater is named for its ‘shearing’ flight, in which it flies with stiffly held wings just centimetres above the ocean waves.
Considered to be the most threatened seabird in the Mediterranean, the Balearic shearwater is a medium-sized shearwater which breeds only on the Balearic Islands, in the western Mediterranean Sea. This species spends most of its time out at sea, where it dives into the water to catch fish and squid, using its long, sharp beak to capture its slippery prey. The Balearic shearwater returns to land to breed between February and June, and each pair lays a single large egg, usually in a small cave, cavity or under a boulder. Breeding pairs may remain together for many years. At the end of the breeding season, some Balearic shearwaters migrate northwards to winter in the Bay of Biscay, and may reach as far north as the United Kingdom and Scandinavia.
The main threats to the Balearic shearwater include predation by introduced mammals and entanglement in fishing gear. The breeding habitat of this species is threatened by urbanisation and by introduced rabbits, which compete with the birds for nesting sites, and the Balearic shearwater may also be negatively affected by pollution, oil spills and a reduction in prey abundance. As part of a recovery plan in place for the Balearic shearwater, rats have been eradicated from a number of breeding sites and a number of protected areas have been created. Studies into the species’ biology and populations are also being carried out. Efforts are underway to assess the problem of bycatch in fisheries, and awareness campaigns, together with mitigation measures, will be important in addressing this threat.
Find out more about seabird conservation at the BirdLife International Global Seabird Programme.
You can also read more about UK marine species in our National Marine Week guest blog.
Liz Shaw, ARKive Text Author