In my last post I mentioned that the juvenal plumage of type 4 and type 2 Red Crossbills seemed to be consistently different, and here are two photos that illustrate the differences.
Variation in juvenal plumage of Red Crossbill Read More »
Last month (late Aug 2010) I had the pleasure of spending some time at the Nature Conservancy’s Pine Butte Guest Ranch in Montana, where an irruption of Red Crossbills was in full swing. Each day around the ranch I saw and heard hundreds of crossbills, of two main call types, and these offered a great
Red Crossbill call types act like species Read More »
Up until the 1980s, permanent sea ice north of Canada and Russia would have been a substantial barrier to the movement of birds around the Arctic Ocean, inhibiting passage east or west along the northern shores of North America and Siberia. As can be seen in the two images above, however, those barriers have almost
Birding and a warming arctic Read More »
An article in the Aug 28, 2010 edition of the New York Times – Warning to Birds: All-Glass Buildings Ahead – describes recent developments in window technology to prevent bird collisions, which is very encouraging because it demonstrates a recognition of the issue by the major news media and by industry. Thanks to the work being done
New York Times on windows and birds Read More »
These two species (recently split) are extremely similar in appearance. No significant differences exist in size or shape, and plumage differences are subtle and mostly overlapping. Songs differ slightly but consistently, and call notes (year round) are the most different. Voice, especially call, will be the best way to distinguish them, and identifying individual birds
Distinguishing Pacific and Winter Wrens Read More »
Maps updated with comments received as of 11 Aug 2010 In the 51st supplement of the AOU Checklist (July 2010), Whip-poor-will is split into Eastern and Mexican species. Basic identification of these two species is already covered in the Sibley Guide to Birds, but range maps need to be updated. Below are maps showing the range
New draft range maps for Whip-poor-will Read More »
Maps updated with comments received as of 11 Aug 2010 In the 51st supplement of the AOU Checklist (July 2010), Winter Wren is split into Eastern and Western species. Basic identification of these two species is already covered in the Sibley Guide to Birds, but range maps need to be updated. Below are maps showing
New draft range maps for Winter Wren Read More »
The North American Checklist Committee of the AOU has published the 51st supplement to the AOU Checklist of North American Birds, which includes two major splits, some name changes (mostly from the creation of new genera), and some big changes in higher-level taxonomy. Below is a summary of the changes to English and Scientific names
New bird names in the 51st AOU Checklist supplement Read More »
The book Sibley’s Birding Basics has been translated into Spanish. More details and ordering info can be found at the Corbidi website (also in Spanish).
Birding Basics – Now in Spanish! Read More »
The eGuide for iPhone was recently updated with all new high-resolution images which can now be displayed full screen; a cleaner and simpler navigation interface, and dozens of additional sounds. More details are here. Several users have reported issues with some of the new sounds added in this update. Uninstalling and reinstalling the program seems
Updates to the Sibley eGuide to Birds of North America Read More »