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a repository of tracking data from researchers across the world, shows
what probably could be guessed, that seabirds are likely to be met across
the world’s oceans. That observation needs refining if the aim is to iden-
tify hotspots. The process has been set in train by Ben Lascelles, for
many years leader of the marine team at BirdLife International. This
organisation has pioneered the identification of so- called Important
Bird Areas (IBAs) on land. Designated according to rigorous criteria,
these are areas where, for example, large numbers of birds, or a signifi-
cant proportion (exceeding 1 percent) of a species’ population, or a very
rare species are found.
Transferring the IBA concept to the marine realm is not straightfor-
ward. Here are some of the problems. Given the immense tracts over
which some seabird species disperse, there will be areas that are impor-
tant at one time of year, only to be totally unvisited at other times.
There is no guarantee that important feeding areas will not shift from
year to year as ocean currents shift. The tracking data on a species are
derived from a relatively small number of individuals, raising questions
about how representative the tracked individuals may or may not be,
and creating uncertainty about exactly how many individual birds are
using what appear to be the key areas. Nevertheless the Lascelles study^20
took due account of these issues and identified 4.3 percent of the world’s
oceans as meeting IBA criteria, albeit with obvious gaps in, for example,
the Bering and Barents Seas where there has been relatively little sea-
bird tracking.
Four percent provides an encouraging start to the discussion. As a
modest value, it avoids the risk that the seabird conservationists are
perceived to be ‘asking for the world’, especially as protected zones al-
ready established for other reasons are likely to indirectly benefit birds.
For example, along the Mediterranean coast of France where the scenery
is gorgeous and the yachts swanky, three areas set aside primarily to pre-
serve coastal fish like the Dusky Grouper and deep- sea ecosystems, have
proven to be key feeding areas for the Yelkouan Shearwater.^21 Slightly
further west, Critically Endangered Balearic Shearwaters that breed on
Majorca head to the Catalan coast of Spain when feeding during in-
cubation. Much of that feeding activity occurs within offshore zones