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Message: <blockquote data-quote="Jane Turner" data-source="post: 1472402" data-attributes="member: 4350">Hi CauI've had another go at estimating wing length - using both available "wing bits"  I'm still getting numbers that are right at the top end for a Nuthatch.Attempt 1: The green line drawn along the longest available primary of the Portuguese putative Nuthatch (ppn <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" /> ) The red and orange line is drawn against a living bird. There is an assumption that the primaries and the leading edge of the wing are in the same plane (and a risk that there will be a small over estimation if the primaries are more out of plane than the leading edge of the wing).  There is a further assumption that the base of the primaries are located approx half way up the coverts.  Without dismantling a bird I can't verify that, but it seems reasonable. That line is then scaled back against the green line, giving an answer of at least 86mm.  Add to that that the measurements I quoted for Nuthatch are maximum flattened chord, and that some of the primary is out of shot.  It also assumes that the primary is the longest primary.Attempt 2: Using the right wing, shown on the left, which has both the primary coverts and the alula attached.  The dark blue line shows the ratio of feather tip to longest each primary covert and alula.  This is then scaled back against the living bird, showing that the primary that is attached to the dead bird's wing can't be the longest, if this bird is a Nuthatch.  Perhaps that is the limit of what can be safely extracted from the photo..... but carrying on for fun, if you make an assumption of how long the longest primary should be in relation to the separation between the alula and the pcs, then you get a figure of c.100mm based on Nuthatch geometry!  10% accuracy is reasonable to assume, so again you are looking at >90mm.I'm getting 14mm for bill to nostril.I wonder if there are any corpses on the tideline to dismember <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" /></blockquote>

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