Tail Variations

My trusty Kaufman bird guide describes identifiable American Kestrel traits including a plain, two-toned tail: "Male has a red-brown tail with black tip." 

Kaufman's American Kestrel images

That's why I always scratch my head when I see Aldo's molted tail feathers. They never seem to match Kaufman's image of a solid brown tail. Even when I search the internet for kestrel tail photos, most depict this definition. Aldo's tail is much more interesting:

Aldo the American Kestrel's molted tail feathers from this summer.

There are some solid brown areas with black along the tip, but there is also spots of blue and checkered black and white. I'm not sure how unusual this tail is. One naturalist saw an atypically-tailed kestrel and noted, "this marks only the third time that I’ve observed wild kestrels with unusually marked tails." Others have documented frequent variation while banding kestrels. There is even variation in Aldo's tail from year to year - it always looks a little different. 

While most animals seem to stick to species-specific color patterns, it's curious to see these variations. Then again, maybe there's more individuality in nature than we notice. Maybe we just need to look more closely!