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Note the structure of the wing.

Yes, here he goes again, harping on things that can't be seen very well on birds.

Some of that may be true, but we have a photo, and we can see it quite well. Swallows are long-winged aerialists. That foraging style (like every foraging style) imposes constraints on wing shape and structure. Relative to their primaries, swallows have fairly small secondaries.

First, on the provided photo (see the cropped and edited version below), the blue line indicates the separation between primaries (to the left of the line) and secondaries. From this, we can see that the breadth of the six or so secondaries occupies nearly half of the length of the wing, despite that there are 10 primaries. Compare that to the wing of the Barn Swallow, whose 10 primaries make up a much larger portion of the wing than on the Cedar Waxwing.

Yes, Cedar Waxwings spend some time flycatching, but the species is not a flycatching obligate. Most of their food is small fruits that they generally don't catch by chasing after them in the air.

Swifts take this difference in distribution of wing length between primaries and secondaries to an even greater extent than do swallows; their secondaries are even smaller.

Oh, one side note that I wanted to point out, but forgot. Note the tail of the Barn Swallow. If you're looking at swallow that has white tail spots and you're standing or sitting or lying within the boundaries of the ABA Area, your swallow is a Barn Swallow. ABSOLUTELY!

 

cedw.JPG

bars.JPG

Edited by Tony Leukering
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@Tony Leukering On these two examples, it seems pretty clear to me where the primaries stop and the secondaries begin. Is that always the case? What is the technical distinction between the primaries and the secondaries? Or, to ask it another way, what do I look for when distinguishing primaries from secondaries while standing under a bird in flight (like these above examples)?

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Secondaries are, for the most part, shorter than most primaries on an individual wing. Yes, the flex point between pp and ss is typically relatively obvious. Secondaries provide lift, so are generally broader than pp, which provide thrust.

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4 hours ago, Tony Leukering said:

flex point between pp and ss

One more question. Is "pp" shorthand for a specific feather or all the primary feathers. I've seen you use it numerous times (e.g. pp projection) and had been assuming it generally meant primaries. If so, why "pp", there's only one p in primaries?

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7 hours ago, neilpa said:

One more question. Is "pp" shorthand for a specific feather or all the primary feathers. I've seen you use it numerous times (e.g. pp projection) and had been assuming it generally meant primaries. If so, why "pp", there's only one p in primaries?

A single “p” means one primary, with that primary usually indicated by number; “pp” is plural.

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