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Number of species: 72

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Alder Flycatcher - Empidonax alnorum

Alder Flycatchers of all ages undergo a nearly complete to complete molt during winter, therefore all in spring are identifiable only as AHY except for a few SY individuals that have retained juvenile feathers. Sexes are identical in plumage; breeding females have a brood patch, but males have a poorly developed cloacal protuberance and may be more difficult to identify with confidence.

Alder and Willow Flycatcher are nearly identical in appearance and are usually identified reliably only through vocalizations; collectively they are referred to as Traill's Flycatcher. The description provided likely applies also to eastern Willow Flycatcher, but not to western Willow Flycatcher.

Quick Tips:

  • Look at the wing bars, which are buffy on HY individuals but whitish on older birds.
  • Examine the rectrices, which are narrow and pointed on HY birds, but broader and more rounded on older ones.
  • Check for an eccentric molt limit among the primaries and secondaries, with retained faded juvenile feathers among the inner primaries and/or outer secondaries indicating a SY bird.

Species account prepared by McGill Bird Observatory

Click on any image below to bring up the side-by-side comparison tool.
Age / Sex  Image sets 
Hatch year / Unknown
Upperparts brownish, with buffy wing bars; rectrices narrow and pointed.
Thumbnail - BS-2580-22061-Empidonax_alnorum-578.jpg

Thumbnail - LL4-2640-37893-Empidonax_alnorum_AOU_7_52-1237.jpg Thumbnail - LL4-2640-37893-Empidonax_alnorum_AOU_7_52-1238.jpg Thumbnail - LL4-2640-37893-Empidonax_alnorum_AOU_7_52-1239.jpg
After hatch year / Unknown
Upperparts greenish, with whitish wing bars; rectrices relatively broad and rounded.
Thumbnail - BS-2580-23394-Empidonax_alnorum-579.jpg

Thumbnail - BS-2610-91938-Empidonax_alnorum-581.jpg Thumbnail - BS-2610-91938-Empidonax_alnorum-580.jpg

Thumbnail - LL4-2640-37977-Empidonax_alnorum_AOU_7_52-1265.jpg Thumbnail - LL4-2640-37977-Empidonax_alnorum_AOU_7_52-1266.jpg Thumbnail - LL4-2640-37977-Empidonax_alnorum_AOU_7_52-1267.jpg
Second year / Unknown
Upperparts greenish, with whitish wing bars; one or more retained brownish and worn juvenile inner primaries or outer secondaries, contrasting with fresher greenish feathers on rest of wing.
Thumbnail - MH3-NA_227-Empidonax_alnorum_AOU_7_52-640.jpg Thumbnail - MH3-NA_227-Empidonax_alnorum_AOU_7_52-638.jpg Thumbnail - MH3-NA_227-Empidonax_alnorum_AOU_7_52-639.jpg
After second year / Unknown
Thumbnail - MH3-NA_226-Empidonax_alnorum_AOU_7_52-637.jpg Thumbnail - MH3-NA_226-Empidonax_alnorum_AOU_7_52-635.jpg Thumbnail - MH3-NA_226-Empidonax_alnorum_AOU_7_52-636.jpg

Additional age / sex class descriptions

The following additional age / sex class descriptions were found for this species:
Age / Sex   Age / Sex class description
Juvenile / Unknown Upperparts brownish, with buffy wing bars; rectrices narrow and pointed.
Number of species: 72

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