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IDENTIFY FEATHER: DETERMINING FEATHER POSITION

How to Determine Feather Position

If you know the position of the feather you are trying to identify, you can significantly narrow your search. If you think you know your feather’s position, you can select it via the optional "Choose Feather Position" dropdown menu on the Search For Similar Feather page. Choices include:

  • Show all wing feathers (both primaries and secondaries)
  • Show primaries
  • Show secondaries
  • Show tail feathers only

If you’re not sure, continue to read the following tutorial which will help you determine your feather’s position.

The Feather Atlas illustrates flight feathers, meaning the primaries (outer wing feathers), secondaries (inner wing feathers) and rectrices, or tail feathers.  The positions of primaries and secondaries on a spread wing are illustrated in the Glossary.

For birds in which the primaries and secondaries differ markedly in size, shape, or pattern, we provide separate scans for these two types of wing feathers.  Examples include eagles and most waterfowl.  For other birds, we include both primaries and secondaries in a single “wing feather” scan.  Such scans always show at least the outer 6 primaries, since these feathers often have distinctive shapes useful in identification.

Overview of Feather Characteristics

PRIMARY WING FEATHERS

Primary Wing Feathers

  • elongate, finger-like tips on outer primaries, especially in birds of prey
  • pointed tips
  • in waterfowl and some other groups, a waxy-looking patch of tegmen on the underside
  • very long quills

SECONDARY WING FEATHERS

Secondary Wing Feathers

  • rounded tips
  • slightly asymmetrical shape (neither strongly asymmetrical or exactly symmetrical)
  • in dabbling ducks, a colorful patch in the mid-vane
  • long quills

 

TAIL FEATHERS

Tail Feathers

  • outer feathers very asymmetrical
  • central feathers exactly symmetrical
  • may be short (e.g. ducks) or long and tapered (e.g. pheasant), but without finger-like tips
  • in woodpeckers, stiff, sharply pointed tips
  • short quills

Primary Wing FeathersCharacters of Primary Wing Feathers:

Primaries are the outer wing feathers, attached to the bird’s small, fused “hand” bones.  Most groups of birds have 10 primaries.  In most birds, primaries have pointed, as opposed to rounded or square, tips.  Note, however, that the inner primaries often closely resemble the outer secondaries in shape.  Primaries are most easily recognized in soaring birds, such as many birds of prey, in which the outer primaries have elongated finger-like tips formed by a distinct notch in the posterior vane, and sometimes by emargination in the anterior vane (see the detailed primary feather illustration in the Glossary).  Because primaries provide most of the power in flight, they are strongly attached to the wing by long quills.

A special feature of the primaries of some birds is a waxy-looking patch on the underside of the feather along the shaft.  This patch is called tegmen. (Please insert correct link). It is most strongly developed in waterfowl, but is also seen in some owls, grouse, and gulls.  If your unknown feather has this tegmen patch, it is a primary, and probably from a duck, goose, or swan.

Secondary Wing Feathers Characters of Secondary Wing Feathers: 

Secondaries are the inner wing feathers, attached to the ulna bone of the lower “arm.”  The number of secondaries is highly variable, related to wing length (the Feather Atlas illustrates a maximum of 12 secondaries).  Unlike primaries, secondaries typically have rounded or squared ends, and never have elongate, narrow tips.  Their vanes are usually slightly asymmetrical (the outer vane a bit narrower than the inner vane).  Because they are strongly attached, their quills are quite long.  In dabbling ducks, the secondaries have a brightly colored patch that forms the “speculum” on the spread wing.

Tail FeathersCharacters of Tail Feathers: 

Although the number of tail feathers is quite variable across groups, the most common number is 12.  The left and right tail feathers are mirror images of each other, and so the Feather Atlas illustrates only the right half of the tail, with the outermost feather on the left of the scan, and the central tail feather on the right side.  The outermost tail feather is highly asymmetrical (narrow outer vane, broad inner vane).  The feathers become more symmetrical toward the center, with the two central tail feathers usually exactly symmetrical (vanes on both sides of the shaft equal in width).  There is a similar change in the curvature of the tail feather shafts from outer to central, with the shafts of the outermost tail feathers usually strongly curved, gradually straightening toward the center, with the central tail feathers shafts completely straight.

In some groups of birds, tail feathers are easily recognized.  For example, woodpecker tail feathers have pointed, stiffened tips that are used to brace the bird against tree trunks.  Most duck tail feathers are short, while many gamebird tail feathers are used in display and thus are boldly patterned and/or elongated.  However, in other groups, such as birds of prey, tail feathers and secondaries are difficult to distinguish.  The shape of outer and central tail feathers is usually a giveaway: no secondary is as exactly symmetrical as a central tail feather, or as strongly asymmetrical as an outer tail feather.  Another clue may be short quills:  tail feathers generally have shorter quills than do secondaries, but this can be difficult to judge.

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