Interspecific territoriality by mixed-singing and song-switching Willow Warblers: a possible case of character convergence
11 June 2018
Main paper
By Mike Lawn Abstract Observations of two mixed-singing Willow Warblers Phylloscopus trochilus in Surrey indicated that both birds were interspecifically territorial with Common Chiffchaffs P. collybita, wher...
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