Monday, May 27, 2013

a lesser nighthawk?

I think not!
We hold it in the same high-esteem as we do the Common Nighthawk (Chordeiles minor).

Lesser Nighthawk (C. acutipennis)

Those of us in parts of the southwestern United States enjoy both species every summer.  In the Big Bend Region of Texas, they are both here now.  In the Marathon-area of north Brewster County, they are no doubt as appreciative of that recent rain as we are.  They, of the Family: Caprimulgidae, are entirely insectivorous.  Quite highly adapted for that specialty diet.

People from other parts of Texas and the world can find separating the two difficult at first.  Well, one can find them difficult to separate at second, third, and beyond when not used to seeing both in their region.

Occasionally, we still have to do a double-take.
While in flight, Lessers can be noticed having a slightly shorter wingspan, though not by much.  More noticeable are the more rounded wing-tips of Lessers compared to pointed wing-tips of Commons.  In flight, the white bar looks to be closer to the wingtip in Lessers.

They are less vocal in flight, compared with the noisy Common Nighthawk.  Lessers also fly without the buoyancy in flap and glide.  They generally stay at a lower altitude than the high-flying bouncy, noisy Common Nighthawk.

Great. Now you come across one perched.  Not a position one happens upon every day.  Now how are you going to tell?

Lesser Nighthawk, same individual.
Photo cropped to show "flight" feathers and tail.
When able to view with binoculars, or from a photograph, the Lesser Nighthawk (LENI) holds a few subtle differences:
Look to the long, mostily blackish primary feathers.
Let's look first to the tips of those primaries:  They extend only to the end of the tail, no further.
                                                                    Common Nighthawks'(CONI) extend beyond the tail.
Looking down and left from the tip of those primaries:  Look at that white-bar -->and look up at those gray feathers above it (tertials).  In the LENI, that bar meets or extends past the tertials.
                                                 In the CONI, they do not reach that far.

Finally, look even further down the primaries:  LENI, when perched has small buffy spots visible on the primaries.  In the above photo they don't show too well, which can be the case.  However, if you look again, there are at least 3 buffy/tan dashes, so it is in fact showing a little to us.

A perching Common Nighthawk  lacks this feature.

Learning, re-learning, emphasizing, and re-emphasizing.
We get to do that in the Big Bend Region of far-West Texas.  We are fortunate.  As I was fortunate to be offered an opportunity to view this bird perched.

*Lesser Nighthawk:  photographed today, May 27, at Post Road on my way to Post Park.  South of Marathon only a couple of miles.  Brewster County, TX.

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