Powder down and the Black-crowned Night-Heron
In a footnote here I mentioned that blackish feathers can appear gray because of powder down, and now I will offer a little more explanation.
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Bird Identification
Does Cattle Egret have a dark morph?
On 18 May 1987, while birding at Cape May, NJ, I came across a small group of Cattle Egrets foraging in a field. Accompanying them was the bird in the photos below. In shape and behavior it was identical to all of the other Cattle Egrets, but its head and neck were mostly dark grayish.
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A Mystery Sound
23 Jun 2011 – Concord, MA Sitting at my desk today I was roused by a bird call that I did not immediately recognize. This is a very rare occurrence for me, especially at my house where I spend many hours every day, and I know the birds that are here very well. As the
An apparent hybrid Yellow-billed x Common Loon
On 9 Jun 1987 I was leading a WINGS tour group at Churchill, Manitoba, and we chartered a small boat to go out on the river for an hour or so to see Belugas and look for birds. During this trip I spotted a distant loon on the water, which struck me as being large
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Optical illusions and bird identification
Here is a classic optical illusion – the three horizontal lines in the image below are all the same length. Yes, they are identical (move your cursor over the image to see the proof). I’ve been pondering this illusion and wondering how often we see similar effects in bird identification. I suspect that a lot
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Distinguishing Interior West from Western Taiga White-crowned Sparrows
See my detailed discussion of White-crowned subspecies here, which needs updating with the information below. In early May 2011 I spent several days in southeastern Arizona, and devoted a lot of time to studying the White-crowned Sparrows. At that date most of them were migrant Interior West birds of subspecies Z. l. oriantha. Most of
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A “mystery” oriole and the limitations of identification by impression
On 9 May 2011 several birders saw and heard a strange oriole in Georgetown, South Carolina (photos here). They identified it as a Scott’s Oriole, a first state record and the first spring record in the east. When other birders saw the photos, some questioned why the bird was not an Orchard Oriole (common in
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Intergradation between Mexican Duck and Mallard in Arizona
The Mexican Duck was formerly considered a species (Anas diazi), and is currently lumped with Mallard (as subspecies Anas platyrhynchos diazi), but recent DNA studies suggest that Mottled Duck (not Mallard) is its closest relative (McCracken et al. 2001). Whatever its genetic background, it is clear from field observations that Mexican Ducks and Mallards interbreed
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Three interesting Brant from Massachusetts
Note: I’m preparing posts on the range and identification of Brant subspecies, which will help make the following more understandable to those who are not already well-versed in the intricacies of Brant. Over the last fifteen or so years I have seen several odd “gray-bellied” Brant along the US Atlantic coast. This spring I finally
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Identifying subspecies by behavior – Savannah Sparrow
Identifying subspecies adds richness to your birding by adding another layer of understanding. What’s more, during spring migration, behavior can offer a quick and fairly reliable clue to use when distinguishing local breeders from migrants. This is simply an extension of a bit of advice often given for identifying shorebirds: to watch for birds around
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