MARSH WARBLER 



throat {Sylvia cinerea) call note, Pied Wagtail (Motacilla 

 lugubris), Blue-headed Wagtail (Motacilla flava), Yellow 

 Bunting (Emberiza citrinella), Green Woodpecker (Gecinus 

 viriclis), Oyster-catcher (Hcematopus osiralegus), Black-tailed 

 Godwit (Limosa belgica), Common Tern (Sterna fluviatilis), 

 Common Bedshank (Totanus calldris), Lapwing (Vanellus 

 vulgaris), Meadow-Pipit (Antlius pratensis), Skylark (Alauda 

 arvensis), Bedstart (Buticilla pho&mcurus), Starling (Stumus 

 vulgaris), and Magpie (Pica rustica). The imitations are to 

 a large extent copies of sounds produced by the inhabitants 

 of the surrounding district. For instance, the cries of the 

 Black-tailed Godwit, Bedshank and Oyster-Catcher are repro- 

 duced in Holland where those birds are everywhere abundant. 

 Any cry, call note, or song is liable to be reproduced imme- 

 diately, if only it is uttered sufficiently close to a male 

 that is singing, or if it happens to be particularly loud 

 or distinct, and as a rule no hesitation is shown by the 

 imitator in incorporating the alien sound with its true song. 

 So easily does the imitation flow from the throat of the 

 bird, and so natural a sequence does it seem to be of the 

 vocal effort, that an observer who had not just heard the 

 sound which was copied might readily regard it as a revival 

 of phrases previously associated. Nevertheless the majority 

 of the imitations are due to revival. This can be proved 

 in two ways. Firstly by the fact that a species is some- 

 times imitated which does not inhabit the surrounding- 

 neighbourhood, as for instance when a male in a midland 

 county reproduces the song of Savi's Warbler, and secondly 

 by noting the sequence of imitative strains. This latter 

 feature requires some further consideration. The question 

 is sometimes asked whether the sequence is alwaj^s similar 

 in the same individual. I have satisfied myself that it 

 is not. The cries of different species are not reproduced 

 in rotation but are interspersed throughout the song in no 

 definite order. From time to time, whilst listening to 

 different males, I have rapidly written down the species 



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