Warbler Guy, given I live in the SF Bay Area, which warbler species are the most common to see during the non-breeding season (i.e., overwintering species)?

Good question, Sheehi (in Fairfield).

In general, in correct habitat, below I list the order (from most common to rarest) for abundance of wood-warbler species in the SF Bay Area during the non-breeding season. I suggest only the initial two on the following list — Yellow-rumped and Common Yellowthroat — are common to detect throughout the SF Bay Area during the non-breeding season:

(Orange-crowned Warbler, above, a common SF Bay breeding species, but rare to absent during the non-breeding season)

1. Yellow-rumped Warbler

2. Common Yellowthroat

3. Depending on which habitat you visit, the next most common species to detect could be:

Orange-crowned Warbler (strongest contender for the 3rd spot; see above photo)
Hermit Warbler (rare to absent during the non-breeding season)
Wilson's Warbler (rare to absent during the non-breeding season)
Palm Warbler (seen annually during the non-breeding months, but never common in the SF Bay
Area during the "winter" months.....most common seen in during autumn migration along the coast, especially within Point Reyes National Seashore)
Black-throated Gray Warbler (rare, but annually seen during the winter, and, if so, during the West Marin Christmas Bird Count, for example)
Nashville Warbler (rare to absent during the non-breeding season; typically a transient in the SF Bay Area; does not nest here)

Regards, Daniel

warblerwatch.com
(hosts information about my 25+ years of Wildlife Biology services, in addition to my bird tours via the "Bird Tours" tab)

Warbler Guy, Where may I most likely see warblers in northern California near you (or where might I see warblers in Marin County)?

Sunday, January 17, 2010

Warbler Guy, Where may I most likely see warblers this time of year in northern California near you (or where might I see warblers in Marin County)?

Thanks for asking, Jeremy (in Mill Valley, CA).

Here's a great web site to note seven fine Marin County birdwatching spots (i.e., the best birding places in Marin County, and, arguably, some of the finest birding locales in northern California):
http://www.marintrails.com/birds.html

(By the way, my Web site, www.warblerwatch.com, features a button -- "2016 Nature Watch Calendar" -- where you can read several brief accounts that discuss wood-warblers in northern California and, in particular, wood-warblers in Marin County.)

Currently, among the seven on the list, I suggest going to Rock Springs (on Mt. Tamalpais) and
Muddy Hollow (within Point Reyes National Seashore, a paramount, iconic place on the W. Coast to see diverse species of birds in multiple families/orders).

In these two spots where forests occur, the most likely wood-warblers to see currently include TOWNSEND'S WARBLER (non-breeding season resident only; see closest above photo) and YELLOW-RUMPED WARBLER (typically the AUDUBON's subspecies).

At Rock Springs and Muddy Hollow, watch for the much less common (in this order) ORANGE-CROWNED and HERMIT WARBLER, too -- though they are both rare to absent throughout most of Marin Co. during January (Populations of these two neotropical migrants return in late winter and spring, thereby nesting in suitable habitats throughout the County.) Even more rare at this time of year is to see the NASHVILLE WARBLER (above photo, below the headline), though it periodically makes a cameo appearance and, indeed, the local annual Christmas Bird Count surveyors sometimes extract one from the landscape.

The Stinson Beach area is another "hot spot" for periodic sightings of uncommon overwintering/non-breeding season warblers, with NASHVILLE WARBLER and HERMIT WARBLER seen there on 12/5/16 by Peter Pyle. Check out sialia.com under his North Bay Birds listserv post, if you wish directions to the grove of trees where he saw these two species (as I know it's often a prime spot to watch for warblers in December/January annually).

Regards, Daniel

warblerwatch.com

(features my "Birding Tours" information for the 8-hour trips I often lead for birders)

Answer to 11/3/16 quiz, below: Orange-crowned Warbler

....and thanks to those who responded....Several were correct!: Orange-Crowned Warbler (subspecies celata) (Oreothylpis celata celata) (Photo credit: Arlene Ripley)

Quick Quiz: Which wood-warbler is this one (in the photos)?

My friend Jim McGinity in Florida is an excellent birder and bander who temporarily captured this beauty recently......along with these fine photos.

Any guesses as to which species? -- per adding a "comment" below. I'll post the answer in a wee here.

Regards and happy birding, Daniel

warblerwatch.com

Warbler Guy, do you have any advice for IDing "confusing fall warblers?"

People often ask me to share the best ways to identify migrating warblers — especially in the East and Midwest where post-breeding plumages can sometimes create identification challenges.

My brief answer is that there’s no replacement for doing your homework in the field. Getting out early and often with your binoculars is the best way to see lots of warblers. The more challenging identification episodes you encounter, the faster you become precise with your warbler field skills.

One identification resource I recently found may interest you. It’s an online “chart” that’s found at: http://www.migrationresearch.org/mbo/id/fall_warblers.html

The author, Marcel Gahbauer, does a terrific job of separating 30 species of warblers by various key feather field marks: a) presence of wingbars or not; and b) facial, throat, and undertail characteristics.

Enjoy your autumn birding!

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.

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.