Abstract
The first Elegant Tern Sterna elegans for the Western Palearctic (WP) was found in France in the large colony of Sandwich Terns S sandvicensis at Banc d’Arguin, Gironde, on the southern Atlantic coast of France, in the 1970s (Dubois & Duquet 1991). Initially reported as a Lesser Crested Tern S bengalensis, its identification took years to be solved. Since then, more than 20 Elegant have been recorded in Europe, most of them returning for many years in a row (Stoddart & Batty 2019,den Outer & Ebels 2020). Some have even been born in Europe, as a few pure pairs have bred in Spain since 2009 (Dies et al 2019). The identity of these birds has long been debated, partly because it was difficult to imagine that several individuals of a species breeding exclusively along the coasts of the Pacific would occur in Europe, partly because the phenotypical variation of Elegant was underestimated. One hypothesis was that some or all Elegant-like birds in Europe were hybrids with other species of ‘orange-billed’ terns (see Stoddart & Batty 2019 for more details).