Identification pitfalls and assessment problems. 13 Pallas's Warbler Phylloscopus proregulus

This series, which started in January 1983 (Brit Birds 76: 26-28), is not intended to cover all facets of the identilication of the species concerned, but only the major sources o('error likely to mislead the observer in the field or the person attempting to assess the written evidence. The species concerned are mostly those which were formerly judged by the Rarities Committee*, but which are now t

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