Category Archives: Black-throated blue warbler

Two types of black-throated warblers number among New World bird family

Photo by Skeeze/Pixabay.com The female black-throated green warbler lacks the male’s all-black throat, but she is a striking bird in her own right. Black-throated green warblers and the related black-throated blue warbler are common birds in the Southern Appalachians from April to October.

I’ve enjoyed some lawn chair birding on recent September evenings, delighting in my observations of birds ranging from flycatchers and catbirds to warblers, vireos and hummingbirds. I enjoy my casual study of the daily changes in the bird population present in my yard and adjacent woods. The parade of warblers hasn’t been as productive as in past autumns, but I have managed to spot and identify hooded warbler, American redstart, chestnut-sided warbler, magnolia warbler, Northern parula, and black-throated green warbler visitors.


The black-throated green appeared suddenly in a fast-paced burst of foraging in a cherry tree. Alongside birds such as an Eastern wood-pewee and red-eyed vireo, the warbler gleaned the leaves of the trees for concealed caterpillars. I watched the bird swallow with gusto several of the caterpillars so skillfully plucked with its thin, pointed bill.

The black-throated green warbler and one other species, the black-throated blue warbler, share the appellation of “black-throated,” and rightfully so. Males in the spring look their best with a dark black throat in striking contrast to the rest of their plumage. The female black-throated green shows some black on the throat, but female black-throated blue warblers exhibit no black throat patch. In fact, black-throated blue males and females are extremely different in appearance. Scientists call such dramatic appearances differences “sexual dimorphism.” Among the warblers, this species provides the most striking example of sexual dimorphism of any of the warblers. The male and female do share one identifying mark — a white square near the outer edge of the middle of each wing. This square is usually more pronounced in the male, but it stands out enough that it helps distinguish the female black-throated blue from similar dull-plumaged birds such as vireos. 


German naturalist Johann Friedrich Gmelin described the black-throated blue warbler in 1789. I noted in last week’s column that Gmelin woefully misnamed such warblers as palm warbler and magnolia warbler. With the black-throated blue warbler, Gmelin did a better job. This bird’s scientific name name is the Latin term caerulescens, which translates into English as “turning blue.” The male is a stunning bird. Arguably, the black-throated blue warbler is one of the most distinctive members of the family of wood warblers. The adult male has a black face and cheeks, deep blue upperparts and a clean white underbelly. In contrast, the adult female is olive-brown above and light yellow below. 


When one’s binoculars first focus on a black-throated green warbler, the first impression is likely to be the black, yellow and white feathers in the bird’s plumage. The greenish-yellow coloration that gives this species part of its common name is mostly limited to the bird’s back, which is often not as evident when the bird’s being watched through binoculars.  
Both of the black-throated warblers nest in northeast Tennessee, western North Carolina, and southwestern Virginia. In the spring, the males of both these warblers are persistent singers from prominent perches in the green woodland canopy. Male black-throated greens contribute to the avian chorus by frequently singing a high-pitched song often described as a buzzy zee-zee-zee-zooo-zeet. Male black-throated blues produce a buzzy zee-zee-zeeee. 

The black-throated green warblers currently departing the region will likely travel as far as Mexico, Central America, the West Indies and southern Florida for the colder winter months. Black-throated blue warblers, on the other hand, migrate to the Caribbean for the winter, making their homes on Cuba, Jamaica, Hispaniola and Puerto Rico, as well as other islands. 
Nearly half of the world’s New World warblers spend the months between spring and fall in North America. The other half reside exclusively in Central and South Americas, as well as the Caribbean. Some of the more descriptively named individuals residing in the tropical areas south of North America include flame-throated warbler, crescent-chested warbler, arrowhead warbler, white-rimmed warbler, buff-rumped warbler, golden-bellied warbler, fan-tailed warbler, pink-headed warbler and pale-legged warbler. 


The warblers bring some exciting tropical flair into the hills and hollows of Southern Appalachia for several months every year. I miss them once they’re gone for the winter season, but the promise of their return keeps my spirits buoyed during the cold, darker months until spring. 

Rally to offer sneak peek at bird migration, other nature activities

CapeMayWarbler

Photo by Bryan Stevens • While the Cape May warbler doesn’t breed locally, these warblers are fairly common spring and fall migrants in the region.

The 56th Roan Mountain Fall Naturalists Rally will draw nature enthusiasts from far and wide to this jewel of the Southern Appalachians on the first weekend after Labor Day with programs, nature walks, catered meals, and much more.

The annual Fall Naturalists Rally is always a great opportunity to enjoy the outdoors and, for birders, get a sneak peek at fall migration with any of the walks and programs focusing on our fine feathered friends. The best naturalists in the region volunteer their time and energy to make this a landmark event for people of all ages.

This year’s rally, which is scheduled for Friday-Sunday, Sept. 7-9, will feature guest speakers, Gabrielle Zeiger and Dr. Joey Shaw, for the main programs on Friday and Saturday evenings.

Zeiger’s Friday program, “Zen and the Art of Mushroom Hunting,” will get underway at 7:30 p.m. following a catered dinner at 6:30. Zeiger has been studying mushrooms in the region for 23 years. She considers herself more of a mushroom enthusiast than an expert. She is a member of the North American Mycological Association, and attends their national forays. She is involved in the association’s annual Wildacres foray in the Blue Ridge Mountains near Mount Mitchell in North Carolina.

 

Photos by Bryan Stevens • Mushrooms will feature in one of this year’s evening programs at the Fall Naturalists Rally.

 

Her program will focus on the two basic approaches — looking for good edibles and scientific study — to mushroom hunting. Her talk will touch on both approaches and include basic information on common mushrooms found in the area, species diversity and poisonous versus edible mushrooms. The program will include various types of fungi from gilled mushrooms, boletes, corals, stinkhorns and polypores, as well as the roles that they play in the environment such as decomposition and forest ecology. She will also talk about what mycologists do at forays. Findings will be included regarding 20 years of record keeping at Roan Mountain and scientific information on studies at Mount Mitchell regarding amount of rainfall and diversity of fruiting.

Photos Contributed • From left: Gabrielle Zeiger and Joey Shaw are this year’s featured speakers.

 

Saturday’s program on “Digitizing Tennessee’s One Million Herbarium Specimens,” will also start at 7:30 p.m. followed by a catered meal at 6:30. Dr. Joey Shaw received a bachelor’s of science in biology from the University of Tennessee at Chattanooga in 1998, and that same year began his graduate education in the Department of Botany at the University of Tennessee, Knoxville. In 2001, he received his master’s in botany for a floristic investigation of the Big South Fork National River and Recreation Area in Tennessee and Kentucky. In 2005 he received his Ph.D. from the University of Tennessee, Knoxville, for his work on the phylogeny and phylogeography of the North American plums and molecular evolution of different genetic regions of the chloroplast genome.

Shaw is currently serving the Association of Southeastern Biologists as Past President and will rotate off this Executive Committee in April 2019, after having served for over ten years and in all ranks of that committee. He is also serving as Chair of the Wildflower Pilgrimage Organizing Committee, and in this capacity he organizes this annual event that brings together more than 120 professional biologists with 850 members of the public to participate in more than 150 different events over four days every spring in the Great Smoky Mountains National Park.

Blue-headedVireo

Photo by Bryan Stevens • Blue-headed vireos, such as this bird, are high-elevation summer residents in the region. In the fall, they are also common migrants.

Evening and lunch programs will take place in Roan Mountain State Park’s Conference Center and unless other noted, field trips will leave from the field on the left before the cabins in the park.

In addition to the programs, morning and afternoon walks will be held Saturday and Sunday on a vast array of subjects, including birds, salamanders, butterflies, spiders, snakes, geology, mosses and liverworts. A “moth party” will be held after the Friday and Saturday programs. Larry McDaniel will host this party taking a look at these winged nocturnal insects outside the Conference Center.

Consider joining the Friends of Roan Mountain, if you are not a member. Members get free admission to all Naturalists Rally events and the newsletter, “Friends of Roan Mountain.”

The rally offers catered evening meals by City Market of Elizabethton, as well as brown bag lunches on Saturday. All meals must be pre-paid in advance.

Registration and payment for meals and other activities can be made at the website for Friends of Roan Mountain at friendsofroanmtn.org. The website can also provide a brochure for download that offers a complete schedule and details all the available activities at this year’s rally. Whatever your interest, the Roan Mountain Fall Naturalists Rally is sure to have an activity available. For local birders, it’s often the kick-off to the fall migration season as warblers, vireos, thrushes, tanagers, birds of prey and many other species pass through the region on their way to their wintering grounds.

Tanager-Sept18

Photo by Bryan Stevens • A female scarlet tanager is a study in contrast from her mate with her dull greenish-yellow plumage being much less vibrant than the male’s bright red and black feathers.

World’s coffee drinkers owe debt to pest-eating warbler

Do you like to have a morning cup of coffee as you watch the early-bird arrivals at your backyard feeders? If so, you may want to thank some of the warblers and other neotropical migrants that consume tiny insect pests injurious to coffee farms.

The website Coffeehabitat.com provides an archive of interesting reading material about the connections between coffee farming and many neotropical birds. According to a profile on the black-throated blue warbler at the website, this particular warbler has a strong affinity for wintering on coffee farms.

Coffee.jpg

Photo by Bryan Stevens • Coffee drinkers owe a debt to the black-throated blue warbler.

The black-throated blue warbler is a nesting bird in hardwood and mixed forests in many mountainous regions of eastern Tennessee, southwestern Virginia and western North Carolina. In fact, the species nests as far south as northern Georgia along the Appalachian Mountains. Those birds not nesting in the Appalachians make their summer home in southern Canada, as well as northern states like New York and Pennsylvania.

Thanks to scientific tests of the birds’ feathers, scientists now know that most of the black-throated blue warblers that spend the summer nesting season in the Appalachians are in turn wintering in Puerto Rico and Hispaniola. The black-throated blue warblers from the northern part of the range for the species spend the winter months in Cuba and Jamaica.

I’ve been spending more time than usual in my yard since the arrival of September, and I’ve been rewarded with glimpses of numerous migrating warblers, including Tennessee warbler, Blackburnian warbler, Cape May warbler, black-and-white warbler, chestnut-sided warbler, hooded warbler, Northern waterthrush and black-throated green warbler, as well as a dazzling male black-throated blue warbler.

Warbler-InHand

Photo by Jean Potter • A male black-throated blue warbler, banded for a study on songbirds, is examined closely. This is one of the most beautiful of the warblers.

If you recall the 1980s hit song, “Sharp Dressed Man,” by ZZ Top, perhaps I can give an accurate impression of the male black-throated blue warbler. He a dapper, sprightly fellow with a blue topcoat that dominates first impressions. It’s only after seeing the shock of blue that the observer takes notice of the black throat and the black feathers forming a dark facial mask, as well as a clean divide between the bird’s blue crown and back and the clean white underparts. The male even carries a fresh pocket “handkerchief” in the form of a white block on each wing. This becomes a diagnostic mark in the female’s less impressive version.
The sexes of black-throated blue warbler are the most markedly different among all the warblers. Even the famous early naturalist and painter John James Audubon got confused by the black-throated blue warbler male and female. He even made the mistake of painting a young black-throated blue warbler and misidentifying it as “pine swamp warbler.” The female black-throated blue has nary a trace of black in her feathers. Her plumage is mainly a dull olive-gray with dingy white underparts. Her only tie to her mate when it comes to appearance is her much more modest version of the “pocket handkerchief” on each wing.
In Jamaica, black-throated blue warblers are identified by Coffeehabitat.com as the number one predator of the dreaded coffee berry borer. So, as you raise that cup of affordable morning coffee, thank the black-throated blue warbler for eating all of those harmful pests that, left unchecked, would cause coffee prices to spike.
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Bryan Stevens lives near Roan Mountain, Tennessee. To learn more about birds and other topics from the natural world, friend Stevens on Facebook at https://www.facebook.com/ahoodedwarbler. He is always posting about local birds, wildlife, flowers, insects and much more. If you have a question, wish to make a comment or share a sighting, email ahoodedwarbler@aol.com.

Blackthroated_Blue_Warbler

Photo by U.S. Fish & Wildlife Service/Mark Musselman • Black-throated Blue Warblers are among the birds than call the mountains of Southern Appalachia home during the summer months.