Afghanistan (P), Azerbaijan, Bangladesh, China (mainland) (B), Finland (B), India, Iran [Islamic Republic of] (P), Jordan (P), Kazakhstan (B), Kyrgyzstan (B), Mongolia (B), Nepal, Oman, Pakistan, Russia (Asian) (B), Russia (Central Asian) (B), Russia (European) (B), Sri Lanka, Tajikistan, Turkmenistan, United Arab Emirates, Uzbekistan (B).
Vagrant to Austria, Belgium, Cape Verde, Denmark, Egypt, Estonia, France, Germany, Greece, Hong Kong (China), Israel, Lebanon, Netherlands Antilles, Norway, Spain, Sweden, Turkey, United Kingdom.
Breeds western and south-western Russia east to Kazakhstan (except much of western and south), extreme north-western China (Dzungaria), north-western Mongolia and south-central Siberia (upper R Yenisey). Non-breeding India.
Rarity Status
Currently this species is not classified as a rarity in this country OR information has not been updated.
Population
Estimated population is 500,000 - 5,000,000 (2010).
Booted Warbler (Iduna caligata) [XC830826]
by id from Torhamns udde, Blekinge, Sweden (song)
Subspecies
No subspecies.
Recent molecular-genetic studies suggest that this species and Sykes's Warbler (Iduna rama), Isabelline Warbler (Iduna opaca) and Olivaceous Warbler (Iduna pallida) are closer to Acrocephalus than to current congeners and could be placed in a separate genus, Iduna. Was formerly regarded as conspecific with Sykes's Warbler (Iduna rama), but recent work has revealed that the two have apparently overlapping breeding ranges, and differ in mitochondrial DNA, song, habitat and morphology.
Proposed subspecies annectens (of south-eastern Altai) is considered to be undiagnosable.
BirdLife International Species Factsheet