![\"094\"](\"https:\/\/eontbird.ca\/wp-content\/uploads\/2016\/05\/094.jpg\")
<\/a><\/p>\nFigure 1<\/strong>: Bicknell\u2019s Thrush (C. bicknelli<\/em>). A beautifully preserved specimen showcasing \u201ctypical\u201d Bicknell\u2019s features, such as: warm, reddish-brown tones throughout the upperparts, rich chestnut to the bases of its primaries, plain gray face, extensive yellowish paleness to the lower mandible, and relatively short primary extension (Mclaren 1995). With Bicknell\u2019s, a 1:1 or less ratio (length of the primary extension beyond the tertials to the length of the tertials) is most often observed (Lane & Jaramillo 2000c).<\/p>\n Figure 2<\/strong>: A close-up of Bicknell\u2019s Thrush. The four leftmost birds were taken from their breeding grounds in June and the two rightmost birds were collected in the Kingston area. All the birds were collected between 1977 \u2013 1990. I observed some variation in paleness and variation in yellowish tones throughout the study skin collection. I believe the yellow tones typical to the lower mandible fade in study skins but I am not certain (no reference available). A consistent feature was the amount of paleness throughout. In most cases, the extent of paleness was + 50% of the surface area of the lower mandible. With the Gray-cheeked specimens I observed, the extent was less than 50%. Although a promising ID feature (to be used in conjunction with a whole suite of characters) in the collections room, observing a thrush in the field and being able to discern such a detail is a whole other matter! Although Lane and Jaramillo (2000c) rendered this ID feature unreliable, with today\u2019s impressive digital photographic technology, perhaps a crystal clear close up of bill detail could help further solidify an already strong Bicknell\u2019s candidate when discussing the ID of an intriguing migrant Catharus<\/em> thrush.<\/p>\n<\/a><\/p>\n