The first nuptial plumage is acquired by a partial prenuptial molt, “which involves chiefly the head, chin and throat and not the rest of the plumage. The black chin is assumed by the male and the forehead becomes yellower by moult, wear removing the edgings everywhere so that the streakings below and the throat become jet-black. Young and old become practically indistinguishable, except that the wings and tail of the young bird will average browner and more worn with the edgings duller.” In the female, “the first nuptial plumage differs very little from the first winter, wear bringing out the streaking, while a few feathers are assumed by moult on the chin.”
A complete postnuptial molt occurs in July, producing the adult winter plumage, in which the male “differs somewhat from the first winter, the black of the throat extending uninterruptedly to the apex of the chin, further down on the throat, and in broader stripes on the sides; the wings and tail are blacker and the edgings grayer, especially on the tertiaries; the concealed black of the back more extensive. The veiling is conspicuous on the throat.” The adult winter female is much like the first winter male, “and may have considerable black on the throat, and even the chin.”
The adult nuptial plumage is acquired mainly by wear, with only slight indications of molt, as in the young bird. Dr. Dwight says of the female: “The adult nuptial plumage is, in extreme examples, hardly distinguishable from the male, but usually the black is much restricted and the chin yellow, merely spotted with black.”
Food.—We have only scattering reports on the food of the black-throated green warbler. S. A. Forbes (1883) examined the stomach of one taken in an orchard infested with canker-worms in Illinois, and found it to contain 70 percent of these destructive caterpillars, 15 percent beetles, 5 percent Hemiptera, and the remaining 10 percent Hymenoptera, gnats, coleopterous larvae and mites. Five stomachs of Nebraska birds, collected by Professor Aughey (1878), contained an average of 23 locusts and 21 other insects. Of twelve specimens examined by F. H. King (1883) in Wisconsin, “one had eaten a moth; three, seven caterpillars; one, two diptera; one, six larvae—probably caterpillars; three, eleven beetles; and one, a heteroptera.”
Knight (1908) from Maine writes: “The food consists almost entirely of insects, including beetles, flies, moths, spiders, grubs, larvae and in general the sorts of insects found on the limbs and foliage of the various evergreen trees and especially on the pines. Only rarely do they take their prey in the air, preferring to diligently seek it out among the branches and foliage.”
Probably all the items mentioned in the food of the young are also eaten by the adults. Forbush (1929) adds to the list leaf rollers, leaf-eatingcaterpillars of various kinds, and plant-lice. Evidently these warblers are among the best protectors of our forest trees. W. B. Barrows (1912) says that they are “particularly fond of the berries of the poison-ivy, and to a less extent of those of the junipers.” J. K. Terres (1940) saw them tearing open the nests of tent caterpillars, devouring large quantities of the larvae, which were about three-quarters of an inch long.
Behavior.—Although the black-throated green warbler is one of our tamest and most confiding wood warblers, as shown by the intimate studies of its home life made by several observers, it is much more often heard than seen, for it is a tiny mite and spends most of its time in the tree-tops, gleaning in the foliage of both coniferous and deciduous trees. As Miss Stanwood (1910b) says: “The bird is quick in its movements, but often spends periods of some length on one tree, frequently coming down low to peep inquisitively at an observer, once in a while flying toward a person as if to alight on his hand or head.” Forbush (1929) draws a picture of its confidence: “Like all the wood warblers it is fond of bathing, its bath tub often some pool in a mountain trout brook. One day as I stood beside such a brook, a very lovely male, disregarding my presence, alighted on a stone at my feet, and at once hopped into the clear spring water and performed his ablutions, dipping into the stream and throwing off the sparkling drops in little showers. As he stood there in the sunlight which streamed through an opening in the tree-tops, he left an enduring picture in my memory.”
Those who have studied the home life of the black-throated green warbler have noted its intolerance of some avian intruders in the vicinity of its nest, and its tolerance of others. Pitelka (1940b) writes:
On the eighth day after the hatching, a red squirrel (Sciurus hudsonicus) was observed to approach the blind, coming to within seven feet of the nest. At this time, the female simply left the vicinity of the nest at once and gave no alarm notes. Later the same day, when a young Black and White Warbler approached the nest to a distance of five feet, the female pounced upon it and struck with considerable force. When the intruder returned a second time the female flew at it and drove it away. The indifference to red squirrels and at the same time the offensive reaction toward small passerine intruders (Vireo olivaceusandPenthestes atricapillus) has also been noted by the Nices (1932: 160).
Reading and Hayes (1933) write: “While at the nest, we noticed an inquisitive Chestnut-sided Warbler in a maple a short distance away. He hung around for several minutes, peering at us, until suddenly the male, ably seconded by his mate, attacked him and drove him off. A male Blackburnian met the same fate a little while later, while peacefully hunting insects in the big spruce and, about an hour after that a Red-eyed Vireo changed his intended route at the first warning note and promptly withdrew. Curiously enough, a smallfamily of Black-capped Chickadees travelling slowly through the spruce was totally disregarded.”
The black-throated green warbler is seldom bothered by the cowbird, although mentioned by several writers as imposed upon.
Voice.—Aretas A. Saunders has sent me the following full account of the two songs of the black-throated green warbler: “The quality of the songs is sweet and musical and exceedingly pleasing. With the possible exception of the yellow warbler, this species has the most attractive of theDendroicasongs. The quality has something indescribable that is all its own and enables those familiar with it to recognize the song, however variable the form.
“The black-throated green warbler has two distinct forms of song. Both may be sung by the same individual, and both are equally common in the migration and through the nesting season, so that they cannot be considered as territory and nesting songs. I distinguish them as first and second, but my choice is purely arbitrary. Both are delivered in the same quality. The first is a little longer than the second, for it contains more notes; but it is not proportionately longer, for the notes are shorter.
“The first song has notes on three different pitches. The first notes, three to nine but commonly four or five, are all on the same pitch, usually the highest; the next note, usually a major third lower, is the lowest; the next, and last, is between them. Such a song might be writtensree sree sree sree sree tro tray, all the notes being of equal length. I have 34 records of this song, 23 of which follow this form. A few are arranged with the last note highest, or lowest, or on the same pitch as the first. The first notes are sometimes varied by alternating short and long notes or sometimes are united in a long trill.
“The second song consists of four or five notes only, with a definite time arrangement—3 2 1 1 or 3 2 1 1 1; that is, the first note is three times as long as the last and the second note twice as long. The third and fourth notes are on the same pitch, but the others are on different pitches, so that the song might be writtentreee tray to to, or a 5-note songtreee tray tray to-to tay. The notes, as in the first song, are on three different pitches, but they vary in every possible way as to which note is highest and which lowest, so that there are six possible arrangements of these different pitches in a 4-note song where the last two notes are always on the same pitch. In my collection of 52 records of this song I have samples of all six, and of these 33 are of four notes, while only 19 have the fifth note added.
“Songs of this species vary from 11⁄5to 2 seconds in length, the first song from 12⁄5to 2 seconds, and the second 11⁄5to 14⁄5seconds. The pitch varies from F‴to E‴´, a half tone less than an octave. One peculiar song of the first type, however, was prefixed by a wren-likechatter that was pitched on B″, but the remaining song was normal in pitch. Single songs average about one and a half tones in range, but the majority of the songs of the first type range two tones, and those of the second type two and a half tones.
“The song is to be heard from the first arrival of the species in migration until shortly after the first of August. In 14 seasons the average date of late song in Allegany State Park is August 2, the earliest is July 25, 1927, and the latest August 11, 1935 and 1937. While there is no regular revival of full song after the molt, there is occasional singing of a primitive character.”
C. Russell Mason tells me of a song in which the high, musical note was given six times instead of the usual once. Francis H. Allen has heard some variations in the songs and has sent me these notes: “One bird added at the end of the familiarzee zee zee zoo zeea coda of an intricate and wrenlike quality, and sang this beautiful song constantly. Another introduced a trill after the second note of the ‘trees, trees’ song and ended it with a low note. Another bird sang a variant of the ‘trees, trees’ song, in which it substituted for the final high note a lower-pitchedsu-eet su-eetwithout the familiarzquality.” He and Dr. W. M. Tyler heard one that “sang in addition to one of the characteristic songs of the species an entirely unrecognizable one that went something liketi-ti-ti-ti-ti-zp. The first five notes were very thin and slight with a very short pause before the last one, and the final note was a short emphatic buzz. Once this song ran into a characteristic song without a pause between.” He refers to the ordinary call-note as a distinctivechet, suggesting that of the myrtle warbler, but thinner. “On the occasion in early June, I heard from a male bird a succession of chippering notes which I had formerly attributed to the young alone. He alternated these notes with singing.”
Many other somewhat similar renderings have appeared in print, both in syllables and in human words, most of which seem to recall the song to mind. Some of the best of the wordings aretrees, trees, murmuring treesandsleep, sleep, pretty one, sleep(Torrey, 1885);good Saint Theresa(Maynard, 1896); andtake it, take it, leisurely(Stanwood, 1910b). Miss Stanwood pays this tribute to the charm of the song: “His voice is suggestive of the drowsy summer days, the languor of the breeze dreamily swaying the pines, spruces, firs, and hemlocks. It recalls the incense of evergreens, the fragrance of the wild strawberry, the delicate perfume of the linnea. No other bird voice is so potent to evoke that particular spell of the northern woods.”
The black-throated green warbler is a most persistent singer. The Nices (1932) say that the first warbler "gave 466 songs in a singlehour and more than 14,000 in the 94 hours of observation.” According to Albert R. Brand (1938), the approximate mean number of vibrations per second in the song is 6,025, in the highest note 6,750 and in the lowest note 5,125. This compares with a mean of 8,900 for the black-polled warbler, which is the shrillest passerine bird song.
Field marks.—The conspicuous, bright yellow cheeks, the olive-green back, the prominent black throat, the two white wing bands, and the white outer webs of the lateral tail feathers will distinguish the male in breeding plumage. The female is duller and has less black, or none at all, on the throat. Young birds in the fall are much like the female. See the descriptions under Plumages.
Fall.—The fall migration of the black-throated green warbler begins during the latter part of August, continuing through September and often through much of October. It seems to be a reversal of the route followed in the spring. Similar haunts are frequented in the fall in the company of vast congregations of other species. A remarkable flight of various species of warblers was seen by Rev. W. F. Henninger in Scioto County, Ohio, an account of which is quoted by W. L. Dawson (1903) as follows:
On September 28, 1899, I ran into a company of warblers which I would place conservatively at two thousand individuals. It was like a regular army as it moved up a long sloping hillside, and with wonderful rapidity. The wind was blowing almost a gale from the north, and the birds allowed themselves to be urged before it in the direction of their ultimate retreat, like half-stubborn autumn leaves. Lisping, chipping, whirling, driving, they hurried on and I after at full speed, panting, and wishing devoutly for a better chance to identify the fleeing forms. Arrived at the top of the hill the army suddenly halted and when I arrived breathless I had time to note the arrangement by species, not rigid indeed, but sufficiently striking to command attention. In the center were seen Hooded Warblers and a sprinkling of Chestnut-sides. On either side of these in turn were Black-throated Greens and Sycamores, about two hundred of each; while the wings proper were held by Bay-breasts and Black-polls in enormous numbers.* * *As the birds deployed to feed the specific lines were not quite obliterated.
Winter.—The following notes are contributed by Dr. Alexander F. Skutch: “The black-throated green warbler is an abundant winter resident in the Central American mountains, where it is well distributed on both the Caribbean and Pacific slopes. In Guatemala, it winters from 1,000 to about 8,500 feet above sea-level, but is not abundant at either of these extremes of altitude. Farther south, in Costa Rica, it prefers slightly higher elevations. Here I have not recorded it between 2,000 and 2,900 feet, although the greater part of my bird-watching in the country has been done in this altitudinal belt. From 2,900 feet, where it is rare as a winter resident, it ranges up to nearly 10,000 feet. At this elevation, I found it abundant on the Volcán Irazú in late November. Less sociable than the Townsend warbler,it does not form flocks, and except during the actual period of migration, is more often seen alone than in the company of others of its kind.
“As a rule the black-throated green warbler arrives late, and has rarely been recorded before mid-October. But on August 9, 1933, I found a lone male in full nuptial plumage with a mixed flock of small resident birds in an open oak wood on the Sierra de Tecpán in the Guatemalan highlands. He sang his dreamy, unsubstantial song as he foraged along with his newly found companions. I saw only one other of his kind—or possibly it was the same individual again—before early October, when the species began to arrive on the Sierra de Tecpán in numbers.
“Another early arrival appeared on September 28, 1938, in the yard of the cottage I occupied at Vara Blanca, at an altitude of 5,500 feet on the northern slope of the Cordillera Central of Costa Rica. During the following days, it came every afternoon to forage in the low cypress hedges that surrounded the dwelling. Possibly it was attracted to these because of associations with its native land, for these trimmed cypresses were the only coniferous trees in the vicinity—indeed, in Costa Rica, the warblers find no native conifers save two species ofPodocarpus, a genus whose center of distribution is in the Southern Hemisphere rather than in the North. At times the newly arrived warbler descended to the bare ground in the flower garden, where it appeared to find something edible. On October 2 it was for the first time accompanied by a second of its kind. Throughout the winter months a black-throated green warbler continued to visit these cypress hedges.
“This is another migrant warbler that plucks the dainty white protein corpuscles from the velvety cushions at the bases of the long petioles of the Cecropia tree. In excessively humid highland regions, as at Vara Blanca, the wide, hollow internodes of these trees are much of the time flooded with water, and therefore uninhabitable by the Azteca ants which at lower elevations usually colonize them. In the absence of the ants, whose food these tiny morsels are, the birds find an abundance of them on the Cecropia trees. A number of small native birds, including finches, tanagers, warblers, honeycreepers and ovenbirds (Furnariidae), share them with the migratory warblers.
“By mid-March the males are in resplendent nuptial plumage. On April 27, 1933, I heard a male black-throated green warbler singing among the alder trees beside a rivulet on the Sierra de Tecpán. On April 4 and 5, 1938, a male sang repeatedly at the edge of the forest at Vara Blanca; and from this date until the disappearance of the species from the region on April 14 I often heard their song.
“There is a certain amount of evidence that with the increasing aridity of the dry season the black-throated green warblers withdrawearly in the year from districts on the Pacific slope where they were present during the wetter closing months of the preceding year. Thus, on the Sierra de Tecpán I met none between December 7 and April 20, when the northward movement was in progress, and the birds seen were doubtless transients rather than winter residents. And in the higher parts of the Basin of El General in southern Costa Rica I have recorded the species only in October, November, and December, after which the nearly rainless season begins. But in the wetter climate of Vara Blanca, they were seen throughout February and March until their northward departure in April.
“The black-throated green warbler withdraws from Costa Rica about the middle of April, and by the end of the first week of May has vanished from Guatemala.
“Early dates of fall arrival in Central America are: Guatemala—passim (Griscom), October 15; Sierra de Tecpán, August 9, 1933; Finca Mocá, October 29, 1934. Honduras—Tela, October 26, 1930. Costa Rica—Vara Blanca, September 28, 1937; San José (Underwood), October 16; Basin of El General, October 22, 1936.
“Late dates of spring departure from Central America are: Costa Rica—Juan Viñas (Carriker), April 17; Vara Blanca, April 14, 1938. Guatemala—passim (Griscom), May 4; Sierra de Tecpán, May 6, 1933.”
The following account of its winter haunts in El Salvador by Dickey and van Rossem (1938) is also interesting:
All through the mountainous districts, both in the interior and coastwise, the black-throated green warbler is an extremely common winter visitant; in fact, it constitutes, at levels between 3,500 and 5,000 feet, fully 90 per cent of the nonresident warbler population. The numerous flocks of from a dozen to half a hundred individuals invariably formed the nuclei about which gathered smaller numbers of other insectivorous species resident and nonresident. The black-throated green warbler showed decided preference for the oak and pine association at the altitudes mentioned, although it was by no means confined to such environments.Many were seen in the coffee cover down to 3,000 feet on Mt. Cacaguatique and 2,300 feet at San Salvador. A few birds reach as high as 8,000 feet, at which level they were found in both pines and cloud forest on Los Esesmiles.* * *The average winter range ofvirenslies approximately 3,000 feet below that oftownsendi, although strays and vagrants make the extremes of altitude nearly the same in both cases.
All through the mountainous districts, both in the interior and coastwise, the black-throated green warbler is an extremely common winter visitant; in fact, it constitutes, at levels between 3,500 and 5,000 feet, fully 90 per cent of the nonresident warbler population. The numerous flocks of from a dozen to half a hundred individuals invariably formed the nuclei about which gathered smaller numbers of other insectivorous species resident and nonresident. The black-throated green warbler showed decided preference for the oak and pine association at the altitudes mentioned, although it was by no means confined to such environments.
Many were seen in the coffee cover down to 3,000 feet on Mt. Cacaguatique and 2,300 feet at San Salvador. A few birds reach as high as 8,000 feet, at which level they were found in both pines and cloud forest on Los Esesmiles.* * *The average winter range ofvirenslies approximately 3,000 feet below that oftownsendi, although strays and vagrants make the extremes of altitude nearly the same in both cases.
DISTRIBUTION
Range.—Eastern North America from southern Canada to Panamá.
Breeding range.—The black-throated green warbler breedsnorthto central western and northeastern Alberta (Grande Prairie, Peace River and Chipewyan); central Saskatchewan (Big River and Emma Lake); southern Manitoba (Brandon and Hillside Beach); southernOntario (Lac Seul, Rossport, Chapleau, and Lake Abitibi; casual or accidental at Moose Factory); central Quebec (Mistassini Post, Upper St. Maurice River, Godbout, Mingan, and Natashquan); and casually in southeastern Labrador (Battle Harbor).Eastto southeastern Quebec (Natashquan); southwestern Newfoundland (Spruce Brook and Tompkins); Nova Scotia (Sydney, Halifax, and Barrington); the coast of New England; Long Island (Miller’s Place); northern New Jersey (Demarest and Dover); central Pennsylvania (Pottsville and Carlisle); central Maryland (Thurmont); central and southeastern Virginia (Charlottesville and Dismal Swamp); North Carolina (Lake Mattamuskeet); and central South Carolina (Charleston).Southto South Carolina (Charleston); northern Georgia (Pinelog Mountains and Lookout Mountain); northeastern Alabama (Sand Mountain); southeastern Kentucky (Big Black Mountain and Jackson); central Michigan (Bay City and Mason County); northern Wisconsin (New London and Ladysmith); central Minnesota (Lake Minnetonka, Mille Lacs, and Cass Lake); southwestern Manitoba (Aweme); and southern Alberta (Brooks).Westto western Alberta (Brooks, Glenevis, Sturgeon Lake, and Grande Prairie).
Winter range.—The black-throated green warbler is found in winternorthto southern Texas (Arroya Colorado, Willacy County); and Yucatán (Tunkas and Chichén-Itzá).Eastto Yucatán (Chichén-Itzá); the coast of Quintana Roo; northeastern El Salvador (Mount Cacaguatique); eastern Costa Rica (Volcán Irazú); and central Panamá (Veragua); casual or accidental to northern Colombia (one record; Cincinnati, Santa Marta region).Southto Panamá (Veragua and Volcán de Chiriquí).Westto western Panamá (Volcán de Chiriquí); western Costa Rica (El General); western El Salvador (San Salvador); western Guatemala (Volcán de Agua and Dueñas); Oaxaca (Tehuantepec); western Morelos (Curnavaca); Puebla (Metlatoyuca); southern Tamaulipas (Altamira); probably eastern Nuevo León (Linares); and southern Texas (Santa Maria and Arroya Colorado).
The black-throated green warbler has apparently extended its winter range northward in recent years. Except for a single specimen taken at Brownsville in January 1911, it was not known to winter in Texas until 1933-34, when about 30 birds were seen. Since then it has increased and spread over most of Cameron County and to the southern border of Willacy County. One was recorded on Bull’s Island, S. C., on January 8 and 9, 1940.
The species is also rare or casual in winter or migration in the West Indies: Cuba (Habana and Isle of Pines); Jamaica; Haiti (Île à Vache); Puerto Rico (Adjuntas); and the islands of St. Croix, Guadeloupe, and Dominica; also Watling Island, Bahamas.
The ranges as outlined apply to the entire species of which two geographic races are recognized. The northern black-throated green warbler (D. v. virens) is found in all the breeding range except the coastal region, from southeastern Virginia to South Carolina, which is occupied by Wayne’s black-throated green warbler (D. v. waynei).
Migration.—Late dates of spring departure from the winter home are: Costa Rica—Juan Viñas, April 17. Guatemala—Tecpán, May 6. Tamaulipas—Xicoténcatl, May 11. Cuba—Habana, May 1.
Early dates of spring arrival are: Florida—Key West, March 3. Alabama—Eutaw, April 1. Georgia—Atlanta, March 26. South Carolina—Mount Pleasant, March 22. North Carolina—Raleigh, March 22. Virginia—Lawrenceville, April 3. West Virginia—French Creek, April 10. District of Columbia—Washington, April 18. Pennsylvania—Erie, April 19. New York—Rhinebeck, April 20. Massachusetts—Cambridge, April 19. New Hampshire—Tilton, April 26. Maine—Portland, April 26. New Brunswick—Scotch Lake, May 1. Nova Scotia—Wolfville, May 3. Quebec—Montreal, May 4. Louisiana—Avery Island, March 23. Mississippi—Oxford, March 10. Tennessee, Chattanooga, March 19. Kentucky—Eubanks, March 23. Arkansas—Delight, March 26. Missouri—Forsyth, April 8. Illinois—Murphysboro, April 11. Indiana—Bicknell, April 16. Ohio—Oberlin, April 13. Michigan—Vicksburg, April 13. Ontario—Guelph, April 20. Wisconsin—Milwaukee, April 19. Minnesota—Brainerd, April 25. Texas—Rockport, February 5. Kansas—Independence, April 1. North Dakota—Fargo, May 5. Manitoba—Aweme, April 30. Alberta—Edmonton, May 5.
Late dates of the spring departure of transients are: Florida—Pensacola, May 7. Alabama—Long Island, May 16. Georgia—Athens, May 14. South Carolina—Greenwood, May 17. North Carolina—Chapel Hill, May 24. Virginia—Norfolk, May 26. West Virginia—Fairmont, May 23. District of Columbia—Washington, June 10. Pennsylvania—Beaver, May 27. Louisiana—Lobdell, May 9. Mississippi—Horn Island, May 12. Tennessee—Knoxville, May 31. Arkansas—Delight, May 30. Missouri—St. Louis, May 22. Illinois—Chicago, June 3. Indiana—Notre Dame, June 2. Ohio—Toledo, June 5. Texas—Brownsville, May 15. Oklahoma—Tulsa, May 18. Kansas—Lawrence, May 16. Nebraska—Syracuse, May 27.
Early dates of fall departure are: Alberta—Glenevis, August 30. Manitoba—Brandon, September 24. North Dakota—Fargo, September 19 (bird banded). Nebraska—Stapleton, October 17. Oklahoma—Oklahoma City, November 2. Minnesota—Minneapolis, November 2. Wisconsin—Madison, November 1. Michigan—Detroit, November 1. Ontario—Ottawa, October 25. Ohio—Columbus, October 31. Illinois—Rantoul, October 31. Kentucky—Madisonville,October 24. Tennessee—Memphis, October 28. Mississippi—Gulfport, November 18. Louisiana—New Orleans, November 4. Newfoundland—Tompkins, October 4. Nova Scotia—Sable Island, October 7. New Brunswick—Saint John, October 12. Quebec—Quebec, October 3. Maine—Ellsworth, October 19. Vermont—Woodstock, October 19. Massachusetts—Harvard, November 2. New York—Scarsdale, October 26. Pennsylvania—McKeesport, October 25. District of Columbia—Washington, October 21. North Carolina—Weaverville, October 31. Georgia—Athens, November 1. Alabama—Fairhope, November 19. Florida—Sombrero Key, November 10 (two struck lighthouse, one killed).
Early dates of fall arrival are: North Dakota—Wilton, September 4. Kansas—Lake Quivira, September 6. Oklahoma—Tulsa, August 13. Texas—Cove, July 26. Ohio—Toledo, August 20. Indiana—Waterloo, August 14. Illinois—Chicago, August 15. Kentucky—Versailles, August 13. Missouri—Montier, August 25. Arkansas—Winslow, August 13. Tennessee—Memphis, August 7. Mississippi—Hernando, July 30. Louisiana—Breaux Bridge, August 12. Pennsylvania—Pittsburgh, August 20. District of Columbia—Washington, August 22. West Virginia—Bluefield, August 29.—Virginia—Charlottesville, September 3. North Carolina—Montezuma, August 27. Georgia—Atlanta, September 6. Florida—Pensacola, September 9. Cuba—Habana, September 30. Mexico—Cuernavaca, Morelos, September 14. Guatemala—Tecpán, August 9. Costa Rica—Vara Blanca, September 28.
Banding.—A few interesting records of banded birds are available. One banded at Hanover, N. H., on September 16, 1930, was found dead at Milledgeville, Ga., on February 25, 1935. Since the bird was an adult when banded it had lived at least five years and eight months. Another banded at Groton, Mass., on May 24, 1933, was “caught” at West Memphis, Ark., on October 22, 1933. A third bird, banded at Overbrook, Philadelphia, Pa., was killed by an Indian near Tetela, Oaxaca, Mexico, about April 1, 1936.
Casual records.—A specimen of the black-throated green warbler was collected on one of the Farallon Islands on May 29, 1911, and another seen on June 1. There are three records for Arizona: one collected in Ramsay Canyon, Huachuca Mountains, on May 9, 1895; one recorded seen in the same mountains in August 1932; and one collected May 30, 1933, in Toroweap Valley, Mohave County, on the brink of Grand Canyon. One was noted on the Teton River below Collins, Mont., on June 4, 1916. A specimen was collected at Barr Lake, Colo., May 20, 1909. In Monroe Canyon, Sioux County, Nebr. one was noted October 8, 1920. At Julianehaab, Greenland, a specimen was taken in 1853; and another at Sukkertoppen in the fall of1933. There are three records for Bermuda: May 7, 1878; February 1927; and May 1, 1928. A specimen was secured on the island of Heligoland, Germany, on November 19, 1858.
Egg dates.—Massachusetts: 26 records, May 21 to July 11; 15 records, May 30 to June 10, indicating the height of the season.
New Brunswick: 13 records, June 13 to 28; 9 records, June 5 to 19.
New York: 19 records, May 30 to July 16; 10 records, June 2 to 11.
Nova Scotia: 13 records, June 7 to 28; 9 records, June 13 to 20 (Harris).
DENDROICA VIRENS WAYNEI (Bangs)
WAYNE’S BLACK-THROATED GREEN WARBLER
Contributed by Alexander Sprunt, Jr.
HABITS
It was a silent world, this great cypress swamp where I sought the nest of the Wayne’s black-throated green warbler in the company of the man whose name it bears and who first made it known to science. A vast flooded expanse of trees and water—colorful, eerie, and mysterious—it was a realm of gray-green gloom. Huge trunks towered on all sides; long aisles of wine-dark mirror-smooth water stretched illimitably away among the buttressed columns. The grayness that predominated, from the furrowed knees and smoother trunks of the great trees to the shrouds of moss festooned from their branches, was relieved here and there by contrasting splotches of bright green overhead where occasional shafts of brilliant sunlight penetrated the canopy of feathery foliage.
Our dugout made no sound as it slid along. Only the slight splash of the paddle entering and leaving the water gave evidence of any means of propulsion. Now and again the silence was broken by the calls echoing down the flooded aisles—the clear whistle of the prothonotary warbler ringing sweetly, the full-voiced carol of the yellow-throated warbler, the strident call of the pileated woodpecker answered by the distant cry of a hunting red-shouldered hawk. Occasionally the deep, resonant “whoo-aw” of a barred owl reverberated solemnly among the cypresses, and once a sombre anhinga flapped ahead of the dugout to plunge cleanly into the still water in full career.
But above these evidences of swamp life, above the swish of breaking bass, the crashing splash of a disturbed alligator, the clamor of a startled heron or ibis, sounded one persistent call from the high branches—a song of seven notes, five on the same tone, one ascending, the last descending. It was this call that drew us on, the song of thebird whose nest we sought that morning, Wayne’s warbler, the southern race of the black-throated green warbler.
To find the black-throated green warbler in a cypress swamp might seem strange indeed to one who knows the species in its spruce and balsam highlands, in the rhododendron and laurel thickets of the Blue Ridge, in the evergreens of the Adirondacks and Maine! Yet here it is, one of the characteristic avian dwellers of the warm swamplands of the South Carolina Low Country, arriving in the spring to nest amid the green cypress twigs, the drooping limbs of the magnolias, and the majestic spread of the live oak.
When Arthur T. Wayne of Mount Pleasant, S. C., discovered the first nesting of this race he was sure it was not a typicalDendroica virens virens, and on April 25, 1918 he sent a male to Outram Bangs of the Museum of Comparative Zoology in Cambridge, Mass. Later he sent him six other specimens. Upon comparing them with specimens ofD. v. virens, Bangs (1918) described it as a different race, giving it the name of the discoverer,waynei. Extracts from his published material are illuminating. He states, for instance, that “this series proves to represent a form easily distinguishable from trueDendroica virens(Gmelin). I take great pleasure in naming it after the keen ornithologist and excellent observer and collector who discovered it, and who noticed its peculiarities even without sufficient material with which to compare it.”
The subspecific differences are mainly a duller coloration, less yellowish, and of a paler shade, and the throat patch more restricted. Its principal variation fromvirensis its much smaller and more delicate bill. As Bangs points out, “measurements of a bill so small do not convey the same impression that an actual comparison of specimens does. The bill of the new form when compared to that ofD. v. virens, appears not more than two-thirds as large.” Certainly this is true. So marked is the difference that a specimen ofwayneiplaced amid a score or more ofvirenscan easily be picked out even at some distance.
The southern limit of the breeding range ofvirensappears to be the high mountains of Carolina and Georgia and northern Alabama, usually at elevations of more than 4,000 feet;wayneiis confined to a coastal strip (in some cases less than 5 miles from the ocean) so that the intervening area between it andvirensaverages about 300 miles. In all that distance, no northern black-throated green warbler appears except in scattered and isolated instances. The migratory route ofwayneiis as yet imperfectly known, but sincevirensis so scarce along the lower Atlantic coast as to be virtually absent, and since it has never yet been secured or reported along the Carolina and Georgia or northern Florida coasts, it would seem that any specimen seen in those localities would bewaynei.
Spring.—Wayne (1910) said of this bird in South Carolina: “This species arrives with great regularity [Charleston County] as the following dates will show, viz., March 26, 1890; March 27, 1900; March 27, 1912; March 23, 1916. It is not common until the middle of April and its passage through the coast region requires so long a time that one not acquainted with the migrations of birds might readily believe that it bred here … that this species should remain on the coast until June, and not breed is very surprising.”
At that time he was, of course, unaware that the species contained two races, but, as Outram Bangs has pointed out (1918), these March arrival dates in coastal South Carolina occur when “trueD. virensis still in winter quarters in Mexico and Central America.” Thus, it will be seen that the migration times must vary considerably, and the arrival of the coastal race is in advance of the true species, indicating a different and less distant winter home, another phase to consider when comparing the two.
There is almost a complete dearth of additional information on arrival dates in other southern states. My records of South Carolina arrival dates in recent years do not vary much from Wayne’s, and he has no earlier ones. I have but once encounteredwayneiin spring elsewhere than in South Carolina, this being a specimen observed in full song in Rhetta Lagoon, Cumberland Island, Ga., on April 15, 1932. However, that it was, in fact, a migrant is beyond all question for it is not present in its United States range in late fall and winter.
In his description of the race in 1918, Bangs stated that “it would seem not unlikely that the South Carolina form is resident and non-migratory, and I hope Mr. Wayne will be able to prove whether or not this is so.” This belief of Bangs’ was carried into the A. O. U. Check-List (1931) which gives the range of this form as “resident in the coastal district of South Carolina.” This is not the case;wayneidoes not remain in winter, and is therefore not resident but migratory, as I have previously pointed out (1932).
The migration of this race is as yet imperfectly known. While any coastal migrant black-throated green warbler would probably be referable to it, asvirensappears to keep to the interior when travelling north, as a matter of fact there are almost no records of migratory occurrences. S. A. Grimes (MS.) tells me that he has never observed any black-throated green warbler in the area about Jacksonville, Fla., where he lives and where he is much afield, having had years of experience. Earle K. Greene (MS.) similarly states that his experience of over two years in the Okefenokee Swamp in southern Georgia failed to produce “a single individual.” Strictly in line with his observations are those of Francis Harper (MS.) whose experience in the Okefenokee is even more extensive thanGreene’s. He writes in response to my request, “I have never found the slightest trace of the bird there.” This is strange, as the Okefenokee would seem to be typical habitat for the Wayne’s Warbler, but it evidently does not occur there.
Courtship.—Nothing is known of the courtship behavior of this bird, owing to the difficulty of observation, the very restricted range of the bird, and the dearth of local observers.
Nesting.—Wayne was under the impression that he was the discoverer of the first known nest of this race, but search of the literature reveals that he was in error, though the first nests found were not recognized as those ofwaynei. Wayne secured the first eggs, and these still appear to be the only ones in existence, as all other breeding records deal with young birds. Authentic breeding information is exceedingly scanty, and since this is the case, all of the instances are mentioned herewith.
The first recorded breeding was in coastal North Carolina, and is mentioned by Pearson and the Brimleys (1919). They included it under the black-throated green warbler, as the species at that time had not been divided into two races. One nest was found at La Grange, Lenoir County, in June 1905 (Smithwick), and the other at Lake Ellis, Craven County, June 1910. Adults were seen feeding very young birds.
Continually impressed with the birds’ presence in coastal South Carolina so late in spring, Wayne sought evidences of nesting and, on April 11, 1917, saw a female carrying nesting material in a large cypress swamp in Charleston County, but could not locate the nest. On the twenty-eighth of the same month he detected both a male and female in the same procedure but again failed to find the nest. His (1918) comment on this follows: “The brief account of this bird written in ‘Birds of South Carolina’ is, in the main, correct. Although I had never found it breeding when the book went to the press I was absolutely certain that it really bred on the coast.” A year later, on April 28, 1918, he saw another female engaged in nest building, and again was unable to find the nest. Those who knew Wayne’s untiring energy in such work can readily understand the extreme difficulty experienced in locating this elusive bird’s home. It was on this last date that he secured the type specimen from which Bangs described the race. The following year finally brought success. Wayne (1919) states:
“On March 20, 1919, I visited the place where the type specimen was taken.* * *A few males were heard singing from the topmost branches of tall, gigantic, deciduous trees, and were also seen to fly into very tall pines.” He again visited this spot on April eighteenth with Henry Moessner and the latter located a nest. It "was built in alive oak tree and on the end of a horizontal branch among twigs* * *absolutely concealed* * *about 38 feet above the ground.” Wayne climbed a nearby tree and with Moessner’s help from below, attempted to pull the oak limb toward him in order to reach the nest, when “sad to relate, without a moment’s warning, the limb snapped off and the four fresh eggs that the nest contained were dashed in fragments on the ground.”
The nest itself was preserved, and Wayne describes it as “small and compact, measuring 13⁄4inches in height and 11⁄2inches in depth. It is constructed of strips of fine bark and weed stems, over which is wound externally the black substance that is invariably present in the lining of the nests of Bachman’s Warbler (Vermivora bachmanii). The interior* * *is chiefly composed of a beautiful ochraceous buff substance, doubtless from the unfolding leaves of some fern, and a few feathers.”
On the twenty-eighth, ten days after this nest was found, Wayne returned to the swamp with the Misses Louise Ford and Marion Pellew and found “a very young bird just from the nest and unable to fly more than a few feet, being fed by the male parent, which shows that the birds breed irregularly.”
The party proceeded to another part of the swamp where a female was seen to enter a large magnolia. “Miss Ford* * *saw the female go to her nest* * *built near the extremity of a long drooping magnolia limb, but on the horizontal portion of it and about 25 feet above the ground.” This nest held four heavily incubated eggs, these being the first ones actually taken. This nest had a quantity of caterpillar silk binding the fibres of Spanish and hypnum moss outside, and was “lavishly lined with the beautiful ochraceous buff substance from young fern leaves, as in the first nest.”
Edward S. Dingle (MS.) writes that “on the morning of April 25, 1923, a Wayne’s warbler was observed building in a cypress tree; the bird collected material from the ground and also from the trunk of a large cypress nearby. The male was not seen.” On the third of May following, I accompanied Wayne and Dingle to the site; there Dingle located the nest, climbed the tree, and secured it, with four eggs. This nest was 62 feet from the ground and 5 feet out from the trunk. This is the third, and last nest from South Carolina with eggs, on which data are extant. All, with the exception of the first, were in Wayne’s collection at his death, and are now in the Charleston (S. C.) Museum. The sites in each case, were found by Wayne, but the nests were actually located by Moessner, Dingle, and Miss Ford.
Commenting on these discoveries, Wayne (1919) states: “I have known this bird ever since May 4, 1885 when I took a male in Caw-caw Swamp, Colleton County, S. C., while on a collecting trip with myfriend, the late William Brewster. I gave the bird to him in the flesh, and in his collection it still remains. The nest and eggs have remained unknown until brought to light by this season’s research.”
Russell Richardson (1926) reported black-throated green warblers in the Dismal Swamp, on the North Carolina side, in June. No evidence of nesting was found by him, and he did not, apparently, realize that the birds he saw werewaynei. In 1932 Drs. W. R. McIlwaine and J. J. Murray visited Dismal Swamp on May 23-26, and “found Wayne’s warblers rather common.” From Murray (1932) we find that they “heard two singing males on May 23rd as we came down the Washington Ditch to the Lake; two males singing on the 24th near the entrance to the Feeder Ditch* * *and six males on the 26th.” They also found two family parties of adults feeding small birds on the 24th. One of these parties was near the mouth of the Feeder Ditch; the other a half mile up the Jericho Ditch from the Lake (Drummond).* * *The young birds were out of the nest and could fly well. They looked like big bumble-bees buzzing across from one tree to another; staying rather high up. The adults ranged low in gathering food, both male and female feeding the young birds.
Eggs.—The eggs ofwayneiare similar to those ofvirens. Wayne has described them (1919) as “of a white or whitish color speckled and spotted in the form of a wreath around the larger end with brownish red and lilac.” The sets previously described are the only ones of which the writer is aware, and may be the only ones in collections. Whether any have ever been secured outside of South Carolina is doubtful. Measurements of Wayne’s two sets average 16.79 by 12.25 and 15.12 by 12.03 mm., a trifle under the average for eggs ofvirens. The breeding records for the Dismal Swamp (Virginia) and two localities in North Carolina, concern young birds only.
Plumages.—Data available are not sufficient for a detailed description of the plumages but they are probably the same as those ofvirens.
Food.—No positive information on the food ofwayneiexists, as far as I can ascertain, except that in July 1939, G. H. Jensen examined the stomach contents of a single specimen secured by Howell and Burleigh at Murrells Inlet, S. C., June 5, 1932. It was full and contained 100 percent animal matter, consisting of 3 Lepidoptera larvae, 98 percent; 1Formicasp., 2 percent. That the race is insectivorous goes without saying, but more than that remains to be worked out. Howell (1932) cites Barrows as saying thatvirensconsumes plant lice, span-worms, and leaf-rollers together with berries of poison ivy. Probablywayneiindulges similar tastes.
Behavior.—Wayne’s warbler is essentially a high-ranging bird. It spends much of its time amid the topmost branches of cypress, magnolia, gum, and other swamp trees, rarely descending to even mid-sectionsof this characteristic growth while feeding. Highly restless and exceedingly active in movements, it is constantly on the go and, as a consequence, is rather difficult to see and study satisfactorily, the oft-repeated song being the best indication of its whereabouts. As might be supposed, the female is even more elusive, and flits about like some swamp wraith, silent and mysterious. The failure of as keen an observer as Wayne to locate the nests of building females gives an idea of its secretiveness.
In these respects it differs materially fromvirens, at least in my experience with that race, which is frequency found at rather low elevations. Doubtless the type of growth is responsible, forvirensis a spruce-balsam-hemlock dweller, and these evergreens are dense trees with branches often beginning only a few feet from the ground, so that it can be seen and watched rather easily.
While several authors have referred tovirensas a tame bird, the same cannot be said forwaynei. In years of experience with the latter, I have always found it shy and retiring. Singing freely enough if unaware of observation, it often ceases when it detects an intruder, and since the song is one of the surest means of locating it, great care has to be taken in moving about, particularly near the nest.
The nest is impossible to find without watching the female, for it is more often than not completely invisible from the ground.D. v. wayneiis found in the same habitat with yellow-throated and parula warblers, but, unlike them, never utilizes the hanging clumps of Spanish moss (Tillandsia) in which they invariably nest. I have climbed a tall cypress and collected a nest and eggs ofD. d. dominicawhilewayneiwas singing in the near vicinity. The preference ofwayneifor heavy, old-growth swamp forests is so marked that if this timber is cut out, the bird disappears from the area completely, even though other growth is left standing. In the South Carolina Low Country, this characteristic is shared by both Bachman’s and Swainson’s warblers, both of which nest in heavy swamps.
Voice.—Though it was the cuckoo which Bryant characterized as “a wandering voice,” he might well have written the words with respect to this tiny warbler for the bird is heard far more readily than it is seen. As a songster it is all but indefatigable. Perhaps this is because the depths of the cypress swamps and the old “backwaters” are cooler than the surrounding highlands, but no matter how warm the day, or close the atmosphere, the constantly reiterated, seven-note song resounds through the air most of the day. The ornithologists I have guided to the haunts ofwayneiall agree that the song is very close to that ofvirens. Perhaps it is a shade more deliberate and studied, as might be expected of a southerner! However, to all intents and purposes,it is the same song. I am inclined to describe it as slower and more pronounced, but after all the difference is minor.
Arthur H. Howell (1932) describes the song ofvirensas “a drowsy, drawled ditty of four or five notes,wee-wee-wee-su-see, the next to last note on a lower pitch and the final one distinctly higher.” This portrays quite well the song ofwaynei, except for the number of notes, which are much oftener seven than less, the first five being exactly alike, the sixth descending, and the seventh ascending.
Frank M. Chapman (1907), quoting Gerald Thayer, says ofvirensthat “most of the individuals in a region sing nearly alike … but about one in forty does queer tricks with its voice. Among the commonest of these tricks is the introduction into all parts of the song of a pronounced quaver or tremulo…. The song is sometimes disguised almost past recognition.” He states further that the “deliberate song of five (sometimes six or eight) notes, is the one usually described in books.”
I have never noted any “quaver or tremulo” in the song. It may occur, but in the scores of times I have heard the song it has not taken place. Nor can I recall any song of eight notes. Occasionally,wayneiwill utter only five notes, but this is the marked exception and not the rule. Certainly, individuals in a given region sing exactly alike, and indeed, all the specimens I ever heard sounded alike, except for the occasional slight variation in number of notes.
Fall.—The length of stay ofwayneiin its summer range has not yet been determined with certainty. Few departure dates have been recorded, but in all probability the bird is a rather early migrant. Occurrence of the song decreases markedly after the nesting season, making the birds’ movements much more difficult to trace. It will be recalled that young were noted flying on May twenty-fourth, in the Dismal Swamp of Virginia. South Carolina birds were seen to fly “a few feet” on April twenty-eighth, almost a month earlier. The North Carolina records show that young were noted “in June”, probably early in the month. That multiple broods are raised is also something of an open question, though it seems that in South Carolina two are raised. Henry H. Kopman (1904) states that on July 30, 1897, he took one at Beauvoir, Miss., on the Gulf coast, and later comments (1905) that “Professor Cooke [W. W.] is inclined to think” that the Beauvoir bird was a stray. Probably it was a stray, and in view of what we know today, the chances are that the bird was a specimen ofwaynei. Many of the birds of course linger much later than that; on September 29, 1935, Earle R. Greene [MS.] noted one at Lake Mattamuskeet, N.C. This is doubtless a rather late date and may be taken as about the limit of its stay along the Atlantic coast.
Enough remains to be learned about this most interesting race to keep students busy. The highly attractive type of habitat, the marked isolation of nesting pairs even in a restricted range, the active character and handsome appearance of the bird itself, all these combine to render Wayne’s warbler distinctive and appealing.
DENDROICA CHRYSOPARIA Sclater and Salvin
GOLDEN-CHEEKED WARBLER
HABITS
This elegant warbler is confined in the breeding season to a very narrow range in south-central Texas, the timbered parts of the “Edwards Plateau” region. It has been reported as breeding in Bandera, Bexar, Comal, Concho, Kendall, Kerr, and Tom Green Counties, and rarely north to Bosque and McLennan Counties. It winters in the highlands of southern Mexico and Guatemala.
The golden-cheeked warbler was entirely unknown to early American ornithologists. William Brewster (1879) gives the following brief account of its early history: “The original specimens were procured by Mr. Salvin in Vera Paz, Guatemala. Since that time, with the exception of a male obtained by Mr. Dresser, near San Antonio, Texas, about 1864, no additional ones have apparently been taken. The specimen mentioned by Mr. Purdie was taken by George H. Ragsdale in Bosque County, Texas, April, 1878.” The bird is now well known in the limited region outlined above, and many specimens of the birds, their nests, and their eggs have found their way into collections.
The first comprehensive account of its habits was given to Dr. Chapman (1907) by H. P. Attwater, of San Antonio, Tex. He says of its summer haunts in the counties named above:
The Golden-cheek is not a bird of the forest, being seldom met with in the tall timbered areas in the wilder valleys along the rivers, or in the tall trees which fringe the streams in the cañons; but its favorite haunts are among the smaller growth of trees, on the rough wooded hillsides, and which covers the slopes and “points” leading up from the cañons, and the boulder strewn ridges or “divides” which separate the heads of the creeks. The trees which compose this growth consist chiefly of mountain cedar (juniper), Spanish or mountain oak, black oak, and live oak on the higher ground, and live oak and Spanish oak clumps or thickets on the lower flats among the foothills, interspersed in some localities with dwarf walnut, pecan and hackberry. All these trees grow on an average from 10 to 20 feet high, the cedar often forming almost impenetrable "brakes". Whatever space remains among the oaks and cedars is generally covered with shin oak brush, which is a characteristic feature of the region. The cedar or juniper appears to possess some peculiar attraction for this bird for they are seldom found at any great distance from cedar localities, and they seem to divide the greater part of their time between the cedars and Spanish oaks, searching for Insects, with occasional visits to other oaks, walnuts, etc., but seldom descendingas low as the shin oak brush, which averages four to five feet. It is quite probable that future observations will show, that some favorite insect food which comprises a portion of their “bill of fare,” is found among the cedar foliage.
Spring.—The golden-cheeked warblers arrive in central Texas about the middle of March, sometimes a little earlier or later. The adult males precede the young males and females by about 5 days. Mr. Attwater (Chapman, 1907) says: “The song of the male is the first unmistakable notification of its arrival and within a few days it is quite common and the females are also observed. In the localities described the Golden-cheeked Warbler is by no means a rare bird, and it is by far the most abundant of the few Warblers, which breed in the same region.”
Nesting.—W. H. Werner was apparently the first to find the nest of the golden-cheeked warbler, in Comal County, Tex., in 1878, about which he wrote to Mr. Brewster (1879): “The four nests that I have found were similar in construction, and were built in forks of perpendicular limbs of theJuniperus virginiana, from ten to eighteen feet from the ground. The outside is composed of the inner bark of the above-mentioned tree, interspersed with spider-webs, well fastened to the limb, and in color resembling the bark of the tree on which it is built, so that from a little distance it is difficult to detect the nest.” Two of these nests were examined by Mr. Brewster both so much alike that the following description of one will suffice:
It is placed in a nearly upright fork of a red cedar, between two stout branches to which it is firmly attached. Although a large, deep structure, it by no means belongs to either the bulky, or loosely woven class of bird domiciles, but is, on the contrary, very closely and compactly felted. In general character and appearance it closely resembles the average nest of the Black-throated Green Warbler (Dendroica virens). It is, however, of nearly double the size, in fact, larger than any Wood Warbler’s nest (excepting perhaps that ofD. coronata) with which I am acquainted. It measures as follows: external diameter, 3.50; external depth, 3.45; internal diameter, 1.60; internal depth, 2.00. The exterior is mainly composed of strips of cedar bark, with a slight admixture of fine grass-stems, rootlets, and hemp-like fibres, the whole being kept in place by an occasional wrapping of spider-webs. The interior is beautifully lined with the hair of different quadrupeds and numerous feathers; among the latter, several conspicuous scarlet ones from the Cardinal Grosbeak. The outer surface of the whole presents a grayish, inconspicuous appearance, and from the nature of the component materials is well calculated to escape observation. Indeed, it must depend for concealment upon this protective coloring, as it is in no way sheltered by any surrounding foliage.
Attwater (Chapman, 1907) says: