A shrike present on Long Island NY October-November 2010 was originally (and understandably) identified as a Northern. it received wider attention after Shai Mitra questioned the ID in late November, and for several days generated quite a bit of debate over its identification. Most concurred that it was a Loggerhead, but the reasons were mostly subjective […]
A perplexing shrike Read More »
There are five subspecies of White-crowned Sparrow, and in most parts of North America it is possible to see more than one subspecies during part of the year. Identification of subspecies is covered in the Sibley Guide to Birds and in Dunn et al. 1995. Maps of band recoveries (from the Canadian Atlas of Bird
White-crowned Sparrow subspecies – Where? Read More »
The European Starling is often ignored, or worse, by North American birders, but if you can get past the fact that it’s aggressive, very good at living with humans, and has been in North America “only” since 1890, it’s a fascinating bird. As I looked up some other maps in the Canadian Atlas of Bird
Questions about Starling migration Read More »
In the Sibley Guide to Birds I illustrated Pacific and Atlantic/Gulf populations of Brown Pelican, showing different colors on the throat pouch (red on adult Pacific and olive on immature Pacific; always dark gray on Atlantic birds) and suggesting that these colors could identify the two populations. It turns out that Brown Pelicans in Texas
Red pouches on Brown Pelicans Read More »
For most observers the identification of these two species is simple, and is based entirely on location, with Vaux’s in the west and Chimney in the east. It is extremely rare to see the two species together, which means that few observers ever have the chance to study them in direct comparison, and therefore few
Identifying Chimney and Vaux’s Swifts by wing shape Read More »
If you’ve followed any of the discussions about identifying Red Crossbill call types, you may have given up on taking an active role in crossbill study, thinking that it would require thousands of dollars worth of recording equipment and computer software. Well, that is simply wrong. Most people can enter the field and start identifying crossbills
You too can record and identify Crossbill call types Read More »
I recently checked the bill length to bill depth ratios of Cackling and Canada Geese, expecting to find a consistent and useful difference. The bills of Cackling Geese are often described as “stubby” and I was always under the impression that they were short and relatively deep. Working with the measurements in Pyle (2008, Identification
Bill size, not shape, distinguishes Cackling and Canada Goose Read More »
In discussing the identification of the woodpecker in the Luneau video, my colleagues and I suggested that the extensive white visible in the wings could be accounted for, in part, by the natural twisting of the wings during flight. A bird flying away would show the underside of the wings during the entire downstroke. In the
Wing twisting explained Read More »
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 »
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 »