Birds

The basics of iridescence in hummingbirds

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

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Progress on the orange-throated hummingbird mystery

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

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The mystery of the orange-throated hummingbirds

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

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Can Short-tailed Shearwater be identified in the field?

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

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