Nieuwe moleculaire studie van yakutensis (incl. ncDNA):
Sokolovskis, K, Lundberg, M, Liedvogel, M, Solovyeva, D, Åkesson, S, Willemoes, M & Bensch, S 2019. Phenotypic and genetic characterization of the East Siberian Willow Warbler (Phylloscopus trochilus yakutensis Ticehurst, 1935) in relation to the European subspecies. Journal of Ornithology 160: 721–731.
Doel: "Here we characterize a yakutensis population from its extreme northeast breeding range based on morphology, genetic markers and migratory behaviour."
Conclusie: "... neither phenotypic traits nor the currently available genetic resources provide diagnostic criteria for confidently assigning individual Willow Warblers to a particular subspecies."