I’ve thought more about the “square-peg-in-round-hole” analogy in my previous post, and made a few simple drawings to expand that analogy. In many ways, bird identification is like a matching game. The observed bird (here in black) must be identified by matching it to illustrations in a diagnostic key (the gray shapes here). This is […]
Fitting pegs in holes Read More »
Last week I had the pleasure of spending four days birding at Barrow, Alaska, working on an eider identification project with the US Fish and Wildlife Service. While there I was able to study hundreds of Greater White-fronted Geese that were grazing on the tundra – surprisingly numerous and surprisingly approachable. I’ll write a separate
Ambiguity and bird identification Read More »
Another note from the comments under Sandwich Tern by Joseph Kennedy on 4 September, this deserves a separate discussion (Thanks, Joseph). He writes: I have received a note Stu Wilson concerning the black tern pictures posted from the same date. I guess that I should check feet on the rest of my tern pictures. According
Black Tern and White-winged Tern – leg color Read More »
In an interesting 4 September comment under the Sandwich Tern bill color discussion, Joseph Kennedy presents a photo of a juvenile Royal Tern with partly yellow-orange legs. Compared to one of his photos of juvenile Sandwich with yellow legs, the Royal appears to have brighter leg color. Presumably that is variable, but it would be
Sandwich Tern – leg color Read More »
On Thursday, 27 Sep 2007, I’ll be in New Haven, Connecticut lecturing at Yale’s Peabody Museum (where I spent many afternoons as a teenager in the 1970s) as part of their John H. Ostrom program series. Details here (click on September and scroll down) On 19-21 Oct 2007 I travel to Oklahoma to speak and
Two upcoming events Read More »
An eventful few weeks for bird records in North America: The long-anticipated first nesting record of Lesser Black-backed Gull in North America (even though it hybridized with a Herring Gull) – on Appledore Island, Maine. Green Violetear reaches Maine – the farthest northeast record to date. 19 Aug 2007 on Mount Desert Island; photo here
Size judgment is one of the constant quandaries of bird identification – critically important but fraught with error. In a recent online discussion about these photos of sandpipers in flight, I was intrigued by the question of how I, and others, “just knew” that these birds were too small to be Knot or Pectoral and
Judging size of birds Read More »
Several recent Massachusetts reports of Olive-sided Flycatchers seem to have used the presence of white patches on the sides of the back to age the birds as juveniles. This is incorrect and unfortunately the source of the error seems to be an ambiguous entry in the Sibley Guide – sorry. Both adults and juveniles can
Olive-sided Flycatcher – white patches and age in fall Read More »
— updated Sep 27, 2008 This photo by Greg Lavaty of Texas, generated a lot of discussion on the Texas Birds listserv recently, and brings up some interesting points and questions. First, this is definitely a juvenile Sandwich Tern, and the bill color is pretty typical of a recently fledged bird. Here are some photos of
Sandwich Tern – bill color of juveniles Read More »
Feb. 10, 2005 In late October 2004 I was privileged to visit the Nature Conservancy’s spectacular Santa Cruz Island preserve off the coast of Southern California. This island, along with the other California Channel Islands has been called the “Galapagos of the North” and has long been the focus of biological studies, but became more
Distinguishing Island and Western Scrub-Jays Read More »