The Black-throated Blue Warbler

The Black-throated Blue Warbler (Setophaga caerulescens) is a small passerine bird of the New World warbler family. Its breeding ranges are located in the interior of deciduous and mixed forests in eastern North America. Over the cooler months, it migrates to islands in the Caribbean and Central America. It is a very rarely found in western Europe, where it is considered to be an non-indigenous species. The Black-throated Blue Warbler is sexually dimorphic; the adult male has a black face and cheeks, deep blue upperparts and white underparts, while the adult female is olive-brown above and light yellow below. -Wikipedia