Thanks to reader Anne DuPont for sending in these photos of a pair of Great Blue Herons at Wakodahatchee Wetlands, Delray Beach, Florida. It’s clearly a mated pair, but the female (sexed by behavior) has more white on the head and fore neck, paler legs and bill, white head plumes, paler rust color on the [...]
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posted January 25th, 2012; last edited January 25th, 2012 –– David Sibley posted March 3rd, 2010; last edited April 8th, 2010 –– David Sibley Phenology is the study of the timing of natural events, and I have recently begun to realize how useful it is for distinguishing subspecies of birds. In San Diego in Mar 2009 I noticed differences in behavior and molt timing that were helpful in distinguishing Belding’s and Northern Savannah Sparrows. I wrote about this again [...] posted November 5th, 2007; last edited April 9th, 2010 –– David Sibley Great White Heron Ardea herodias occidentalis updated 13 Nov 2007, thanks to all those who have commented publicly and privately. I’ve backed off a bit from my criticism of the TBRC decision, the more I learn the less clear-cut this seems, although I still think it’s at least a good subspecies. Shaibal Mitra sent me [...] |
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