Wednesday, September 28, 2016

Warbler Guy: What “strange” common names were previously designated for some of our wood-warblers?

What “strange” common names were previously designated for some of our wood-warblers?

(The above Black-Throated Blue female's vastly different appearance in comparison to a definitive male of the species is suggested to be the reason John James Audubon named it a different common name, the Pine Swamp Warbler.)

Common Yellowthroat was once often referred to as Maryland Yellowthroat. John James Audubon mistakenly named two Yellow Warblers as Children’s Warbler. In another instance, Audubon misnamed two juvenile Yellow Warblers as Rathbone’s Warbler.

Audubon was not alone in his naming confusion. Beyond Audubon, naturalist/painter Alexander Wilson also made his share of identification mistakes. Both of these luminaries – as well as other contemporary birding experts in bygone eras – are to be excused because during their tenures little was known about the relationship between plumage changes and corresponding definitive field characteristics.

Audubon’s failed nomenclature decisions periodically continued to surface as he gathered specimens for his paintings. Originally calling a bird specimen he collected in Pennsylvania the Pine Swamp Warbler, he later realized his subject was truly a Black-Throated Blue Warbler.

Later, Audubon was misled by Wilson’s naming procedure into thinking a Blackburnian Warbler was worthy of being designated a new species, the Hemlock Warbler. Audubon, in fact, was never able to correct this misnaming mistake. Another misplay hearkens to May 1812, when Audubon caught a wood-warbler specimen that he named Vigor’s Warbler in honor of Nicholas Vigor, an English naturalist. More correctly, Audubon’s find was an immature Pine Warbler. His confusion was probably the result of the collected individual being in vastly different habitat than its usual pine/needle tree haunts.

Even the Canada Warbler was originally misnamed by Audubon. When he first drew the bird as it perched on the fruiting branch of a magnolia, Audubon suggested it be named the Cypress Swamp Flycatcher. Later he changed his mind, renaming the bird as Bonaparte’s Flycatcher only to again change its designation to Bonaparte’s Flycatching Warbler.

Eventually, it was confirmed that Audubon’s specimen was instead a young female Canada Warbler. Eight years later, Audubon painted the same species and mistakenly called it a Canada Flycatcher.

Friday, September 9, 2016

Warbler Guy, is the American Redstart a vagrant when seen in California during late summer/fall? American Redstarts in Point Reyes National Seashore are vagrant sightings?

Great question, Monica.

My opinion is "no" — given the Birds of North America account for this species states small populations of this species sometimes breed in far n. CA counties.....Thus, in migration, these populations may move south along the coast where, as you suggested, they are sometimes seen at this time of year at the Outer Point within Point Reyes National Seashore.

(Adult, male American Redstart, above)

That written, it's possible some of the American Redstarts seen from central to southern CA during late summer through fall arrive from as far north as southeastern Alaska and the northwest territories (as the northern most extension of its breeding range).

Observing one of these individuals would not qualify as a vagrant, I believe.

However, disoriented dispersing/migrating American Redstart from the East and Midwest would definitely be best termed vagrants, if seen on the West Coast.

Given the above information, a banded individual or so would need to be assessed to determine the precise answer to your question.