Brown tail tips on male eagle: comparison 2008-09, 2009-10 and 2010-11 Breeding seasons

[NewMexiKen]

The mail eagle has retained brown pigment on one or more tips of his tail feathers after undergoing at least two molts over nearly the past three years.  We only recognized this last season, but older photos show that the trait was present for at least the previous season. He may be genetically programmed for this trait. Let's see if we can recognize any behaviors more specific to one or the other of the pair. Flight shots with the tail fanned will be useful in further analysis.

With Jill's permission, I enlarged her recent photos and cropped the tail of the presumed male Bald Eagle.

Jill's photos dated December 21, 2010 show the tip of the LEFT outer tail feather to be dark, and suggests that there are slightly dark streaks on the shafts or extreme tips of the two RIGHT outer tail feathers:





My photos of the presumed male, dated November 29, 2010 confirm Jill's photos (but she has a better camera) :





My photos from two prior breeding season:

2008-2009 Season shows several dark feather tips, with the RIGHT outer tip most prominent-- February 17, 2009:



Photos from last year's 2009-2010 Season show the prominent RIGHT outer tail tip that gave the male, "Brown-Tip," his name--

December 16, 2009:



February 14, 2010