the range of the dartford warbler is restricted to western and southern europe. the total population in 2012 was estimated at 1.1–2.5 million breeding pairs. the largest numbers occur in spain where there were believed to be 983,000–1,750,000 pairs. for reasons that probably include loss of suitable habitat, the spanish population appears to be declining. the species is therefore classed by the international union for conservation of nature as being near threatened.