Blackburian Warbler (Dendroica fusca), El Dorado Park, Maricopa County

This first-fall female Blackburnian Warbler was found by Jack Bartley at El Dorado Park in south Scottsdale on Oct. 17th, 2007 and was subsequently seen by dozens of birders through at least the morning of Oct. 21st.

Blackburnian Warbler is one of the most infrequently reported vagrant eastern North American warblers in the state, with fewer than twenty accepted records in all. The vast majority of the records fall between late September and late October (most of these are from the first three weeks in October), but there are also a few mid-May and late June sightings as well. The last documented sightings in Arizona come from the fall of 2003 when singles were found in Cameron, Coconino and at Morgan City Wash, Maricopa. Blackburnian Warbler is an Arizona Bird Committee review species.

The i.d. of Blackburnian Warbler is usually straightforward and is covered well in the standard field guides. For those not familiar with the species, however, non-adult male plumages can be a little tricky if the bird isn’t seen particularly well and might be confused with dull, non-adult plumaged Townsend’s Warbler or Black-throated Green Warbler. A few features to look for, most of which are illustrated in the photos here of the Scottsdale bird, are the heavily streaked back (especially the bold whitish “braces” in the center of the back), the lack of obvious green tones in the back and crown, the shape of the dark cheek patch (the back lower corner often appears to be continuous with the start of the streaking on the sides of the upper breast, while the upper corner is often joined with the darker nape feathers), and often the presence of a (faint) coronal stripe.

21 October 2007 photo by Oliver Neihuis

19 October 2007 photo by Jim Burns

20 October 2007 photo by Dave Stejskal