Wednesday, May 27, 2020

Warbler Guy, where are the most different kinds of warblers found? How many types or species of warblers exist? Are all warblers migratory or do some stay “close to home”...?

New World wood-warblers (that are not closely related to the various Old World warblers in the Eastern Hemisphere (e.g., Europe, Asia) are often identified to number as 112-115 species, occurring among 24-26 genera. The centers (or “epicenters”) of their breeding areas occur in eastern North America, the West Indies, Mexico and Central America, and Andean South America.

The majority of northern-latitude breeding species migrate, but many island and tropical species are sedentary. Many of these latter species remain close to their birthing areas or perform short-distance, post-breeding altitudinal/elevation migrations. As for myself, I often see 20-30 wood-warbler species during early May when I return to homecoming birding forays in the Midwest (and, concurrently, attend the annual Wisconsin Society For Ornithology conference).

Last year, for example, I was lucky to visit Wisconsin to attend the conference during the peak of neotropical songbird migration, so I tallied more than 25 wood-warbler species. Then, when I returned in August, I began seeing southbound migrants in the northern portion of the state. Milwaukee County (in s. WI) was nearly devoid of warbler detections, except for probable nesting species such as American Redstart and Yellow Warbler.

In contrast, my n. CA residency, yields more warbler species during the breeding season — a result that surprises many people because the West is thought to host far fewer warbler species. For example, in Marin County (Bay Area) where I live, I often detect at least eight warbler species annually and, in the Sierra Nevada Mountains (near Yuba Pass and/or amid the Gold Lakes country off of Highway 49 near Bassetts), I sometimes successfully sleuth out nine warbler species.

Wednesday, May 6, 2020

Does Connecticut Warbler return by late May? Is Connecticut Warbler rare?




Although Connecticut Warbler is not rare, its habit of being a stealthy, skulking, "shy" species results it in being heard more often than seen. In addition, it breeds in habitats that are often inaccessible to birders, including spruce-tamarack bogs and muskeg (as well as poplar woodlands and moist deciduous forests) in northern Minnesota, Wisconsin, Michigan, and central Canada. Individuals return as early as early May to, for example, southern Wisconsin, but it's been known to arrive as late as early June in irregular years. 


In general, as returning migrant, this species is considered a "late" arriving member of the wood-warbler family. Did you know this warbler was not described until Alexander Wilson did so in 1812? A nest for this species was not discovered until 1883, more than 70 years after Wilson's description. Even today, there are few to no rigorous, experimental studies of its general biology from the breeding or wintering ranges.


Sunday, April 19, 2020

Warbler Guy, I saw your San Francisco birding tours note you have seen nesting warblers in the San Francisco Bay Area. The San Francisco Bay Area has warblers nesting here?

Horatio (in Sunnyvale, CA):

Yes, depending on your perch in the SF Bay Area, there's both resident, year-round wood-warbler species as well as neotropical migrants that return annually to nest here.

The following list, below, is a simplified, non-detailed overview of the nesters in Marin County without providing details:

(Note the * = nester as a spring/summer resident and # = a year-round nester that is resident year-round. In addition, it's important to realize that a few individuals of all wood-warblers in the Bay Area may persist throughout the non-breeding season (though the vast bulk of the * species vacate the Bay Area during the non-breeding season. + = non-breeding season resident only).

* and # Common Yellowthroat (with much of the area hosting two subspecies, including the CA Species of Special concern sinuosa subspecies)

Yellow Warbler (extirpated from the majority of previous breeding areas and/or only periodically nesting in previously occupied nesting habitat)

Orange-crowned Warbler (Note this species persists in small numbers throughout the "winter," but the large pulse of returning nesters begins in February and peaks in March.)

Wilson's Warbler

* Yellow-rumped Warbler (ALSO note: LARGE numbers present during the non-breeding season at low elevations, but most of the nesters occur at higher altitudes in select Bay Area locations only.)

* Hermit Warbler

* Black-throated Gray Warbler

* Yellow-breasted Chat (extirpated from portions of its previous breeding range; largely absent throughout most of the SF Bay Area)

MacGillivray's Warbler

Townsend's Warbler (non-breeding season resident only)

Regards to you Horatio and all warbler seekers of this special family....Daniel

warblerwatch.com (hosts my bird guiding and birding tour information via the "Birding Tours" section)

415-382-1827, Novato, CA






Sunday, March 29, 2020

Warbler Guy: Do warblers migrate over the ocean or was this bird (below photo) confused and lost?


Thanks for the question, Kevin.

Here's my answer, though it's a simplified one to your question that deserves more ink than this digital retorte provides.

*

Given your interesting photo of the Black-Throated Gray Warbler that landed on your boat’s deck while amid the Pacific Ocean, it’s 100% certain that your unfortunate friend is lost and wayward from its normal southern migration route. More exact, no wood-warbler species on the West Coast have yet been discovered to migrate to non-breeding/wintering grounds via an oceanic route.

On the West Coast, only disoriented and/or wind blown wood-warblers show up on offshore islands, such as those often seen by bird banders/researchers stationed at the central California chain of islands called the Farallones. Here, banders have captured in their nets various species of so-called eastern wood-warblers. Others, like the Black-Throated Gray in the photo, below, are wayward sojourners desperate for a wayside to rest upon while fighting to survive in a pelagic habitat that offers no food resources.

Unfortunately, the vast majority of wood-warblers seen resting on boat decks, buoys, and rip-rap along coastal and deep water habitats typically are hatch year birds. Most will either perish while traveling over the Pacific ocean before reaching island refugia such as the Farallones or incur high mortality after being set free by banders that discover them. Some researchers suggest eastern wood-warblers found on the West Coast (including Farallone Island individuals") are inherently "dyslexic" in the sense they do not have the orientation design necessary to complete the classic migration routes that their brethren successfully negotiate each spring and autumn on their north and south peregrinations.

Beyond the West Coast, trans-oceanic migration by songbirds is rare -- and, in the wood-warblers seen in N. America north of Mexico, it is only documented to occur in a few species.

One of them, for example, the Blackpoll is known to contain populations that in autumn perform the high-octane feat of an ocean migration route that totals more than 2,150 miles (NE USA/Maritime Provinces to northern South America).

How do researchers know the Blackpoll performs such a magician's stunt annually?

It's because bird bander's in Bermuda (an island east-southeast of the southeastern USA) band birds in the autumn, and, thereby, sometimes catch Blackpoll in their nets. Evidently, Bermuda is in line with the route over which Blackpoll travel during their southbound migration and this small island serves as a stopover wayside area for Blackpoll that wish to stop and "refuel" before leaving to migrate south again at night.

High-octane is an apt description of the Blackpoll's Herculean task because many leave their "staging" grounds en masse with other Blackpolls and fly en route together as heavyweight butterballs while weighing as much as 26 grams (nearly an ounce) at the beginning of their air treks.

By the end of the Blackpolls' long-distance trip, however, they have been documented to have lost half their starting weights. Emaciated and Twiggy-Thin Blackpoll, therefore, in some cases, are known to digest their muscle to serve as a last resort energy source.

While winging south, researchers have figured Blackpolls burn .08 grams per hour during their three to four days of travel, a process that is a non-stop direct flight, if the Blackpoll does not stop at island refugia such as Bermuda. In comparison, such a weight loss program for club members and gym rats on two legs would mean a 20-pound or more evaporation of girth per day (for the typical weight of 6' tall male or 5'6" female).

Now there's a weight loss program that would attract headlines and lead to a manic panic for (I imagine) a best-selling book titled: "Migrating With a TailWind To A Fat-Free Lifestyle." :-)

Regards, Daniel Edelstein

Birding Guide

&

Avian Biologist

warblerwatch.com

Wednesday, March 11, 2020

Warbler Guy, I saw a nectar-drinking warbler at my feeder? Which warblers drink nectar? Warblers act like hummingbirds?

"Yes," Stevie (in Orlando):

Although it sounds strange, a few warbler species visit hummingbird feeders, including
Orange-crowned, Nashville, Virginia, Yellow, Black-throated Green, Prothonotary, and Cape May.



(Above, Orange-crowned Warbler feeding at a hummingbird feeder)

The initial above three species tend to have longer bills that are adapted to successfully obtain
the sweet elixir (that provides them supplementary carbohydrates beyond the protein-rich insects they seek).

Cape May, by the way, even gobbles jelly birders serve to tanagers and orioles in their yards — so be on the watch for warblers at your bird feeders, folks.

Or simply grab your binoculars and enjoy a walk down your favorite trail.

Look for our fine-colored feathered friends that winging their way north, with the imminent return of several likely in the southeast, Mid-atlantic, and, yes, even the upper Midwest where a few anomalous Yellow-rumped Warblers are already present (as over-wintering individuals or early returning migrants by the end of March/early April).

Happy birding to you, Daniel

warblerwatch.com {features several free birding information handouts (including some excellent articles by David Sibley) via my "Birding Links" area and information about my 25+ years of birding tours and bird guiding services (via my "Birding Tours" area)}


Sunday, February 9, 2020

Warbler Guy, I live in the SF Bay Area where I observed in early February a Wilson's Warbler. Do you think it's an early migrant or a non-breeding season resident that is "over-wintering" without migrating?

Good question, Penelope (in San Francisco).

There's a good chance your Wilson's Warbler sighting was over-wintering straggler that did not migrate farther south like the behavior expressed by the vast majority of this species. (See range map, below, courtesy of Birds of North America online.)




male Wilson's Warbler (credit to Martin Meyers)



North-bound migrants that over-winter in, say, Mexico may return as early as mid-March in the SF Bay Area, but your early February sighting is typically too early for a true long-distance migrant.

Nonetheless, it's not uncommon for over-wintering Wilson's Warbler individuals to periodically appear throughout the winter months in the northern latitudes of California, including nearly annually sightings during Christmas Bird Counts in the region.

Monday, January 20, 2020

Warbler Guy, I saw a nectar-drinking warbler at my feeder? Which warblers drink nectar? Warblers act like hummingbirds?


"Yes," Stevie (in Orlando):

Although it sounds strange, a few warbler species visit hummingbird feeders, including
Orange-crowned, Nashville, Virginia, Yellow, Black-throated Green, Prothonotary, and Cape May.



(Above, Orange-crowned Warbler feeding at a hummingbird feeder)

The initial above three species tend to have longer bills that are adapted to successfully obtain
the sweet elixir (that provides them supplementary carbohydrates beyond the protein-rich insects they seek).

Cape May, by the way, even gobbles jelly birders serve to tanagers and orioles in their yards — so be on the watch for warblers at your bird feeders, folks.

Or simply grab your binoculars and enjoy a walk down your favorite trail.

Look for our fine-colored feathered friends that winging their way north, with the imminent return of several likely in the southeast, Mid-atlantic, and, yes, even the upper Midwest where a few anomalous Yellow-rumped Warblers are already present (as over-wintering individuals or early returning migrants by the end of March/early April).

Happy birding to you, Daniel

warblerwatch.com {features several free birding information handouts (including some excellent articles by David Sibley) via my "Birding Links" area and information about my 25+ years of birding tours and bird guiding services (via my "Birding Tours" area)}