I recently commented on this ID problem on MassBird, pointing out differences in details around the eyes. Chipping sparrow has very distinct, narrow whitish arcs below and ABOVE the eye, contrasting with darker gray-brown feathers, and broken at front and BACK by the dark eyeline. Simply looking for these distinct white arcs is a good […]
On identifying Chipping and Clay-colored Sparrows Read More »
After all the discussion of orange-throated and red-throated hummingbirds, I thought it would be helpful to add a brief and simplified summary of how the brilliant iridescent colors of hummingbirds are produced. These are structural colors, not pigment, which means they are reflected by microscopic structural features of the feather surface. The diagram here shows
The basics of iridescence in hummingbirds Read More »
Thanks to Sheri Williamson (author of the Peterson Field Guide to Hummingbirds) and her recent post titled Orange-throated hummingbirds – not so mysterious after all, we have a solid contribution towards understanding the orange throats of some Ruby-throated Hummingbirds, although I contend that mysteries still remain. She explains the details of iridescent color on hummingbirds, and a
Progress on the orange-throated hummingbird mystery Read More »
Patterns of translucence in wing feathers provide useful identification clues for many species of birds – terns, gulls, hawks, and others. Generally the translucent parts of the wing are those where there are fewer layers of feathers to block the light, and less pigment in the feathers. I’ve written about this before in my book
The finer points of wing translucence Read More »
Now updated by a new post Progress on the Orange-throated hummingbird mystery. This adds to my previous post about orange-throated hummingbirds. After hearing from a couple of hummingbird banders affirming that they do not see a change in throat color in the fall as male Ruby-throated Hummingbirds go though their summer molt (and the fact
Orange-throated Hummingbirds: more questions Read More »
Albino and partial albino birds The presence of white feathers on a normally dark bird is the most frequently seen color abnormality. Every birder can expect to encounter white or partly-white birds with some regularity, and the more striking examples will stand out even to novices. All black and brown coloration in birds comes from
Abnormal coloration in birds: Melanin reduction Read More »
Update 16 August: a new post Progress on the orange-throated hummingbird mystery. Update 14 Aug 2011: A follow-up to this post is now available, tempering some of these points and adding more questions – Orange-throated Hummingbirds: more questions. Every year in August and September, a few perplexed observers in eastern North America send out questions about
The mystery of the orange-throated hummingbirds Read More »
The North American Checklist Committee of the AOU has published the 52nd supplement to the AOU Checklist of North American Birds. This supplement includes a lot of changes “under the hood” which will hardly be noticed by the average birder. Several splits result in new names but none have an immediate impact on the North American
New bird names in the 52nd AOU Checklist supplement Read More »
Usually. Experienced observers can almost always identify these species correctly based on careful judgment of head shape and bill size, but these are subtle and subjective impressions, and require a foundation of experience and/or direct comparisons with Sooty. Other features can offer supportive clues or draw attention to a potential Short-tailed, but are not very
Can Short-tailed Shearwater be identified in the field? Read More »
The Eurasian subspecies group of Common Merganser, known by the English name Goosander, has occurred numerous times in the Aleutian Islands of western Alaska, but has never been identified farther east in North America. The American subspecies has some potential to wander to Eurasia, but has never been recorded there. I’ve never seen any in-depth
Distinguishing Eurasian and American Common Merganser Read More »