Of over fifty nests of this bird which I have examined, most of them were securely placed in perpendicular forks of the main limbs of cedar trees, about two-thirds up in the tree; average fifteen feet from the ground. My highest record is twenty-one feet, and lowest six feet. I have also found them in similarpositions in small black oak, mountain oak, walnut and pecan trees.* * *The favorite nesting haunts are isolated patches or clumps of scrubby cedars, with scant foliage, on the summits of the scarped cañon slopes, and in the thick cedar “brakes.” In cedar the older growth of trees is always selected, and no attempt at concealment is made. I have never found a nest in a young thrifty cedar withthickfoliage.The male is always to be heard singing in the vicinity of the nest, and the old nesting localities, and occasionally the same tree is selected apparently and returned to one year after another.
Of over fifty nests of this bird which I have examined, most of them were securely placed in perpendicular forks of the main limbs of cedar trees, about two-thirds up in the tree; average fifteen feet from the ground. My highest record is twenty-one feet, and lowest six feet. I have also found them in similarpositions in small black oak, mountain oak, walnut and pecan trees.* * *The favorite nesting haunts are isolated patches or clumps of scrubby cedars, with scant foliage, on the summits of the scarped cañon slopes, and in the thick cedar “brakes.” In cedar the older growth of trees is always selected, and no attempt at concealment is made. I have never found a nest in a young thrifty cedar withthickfoliage.
The male is always to be heard singing in the vicinity of the nest, and the old nesting localities, and occasionally the same tree is selected apparently and returned to one year after another.
Nearly all the nests reported by others were in cedars and were similar in construction to those described. There are five nests of the golden-cheeked warbler in the Thayer collection in Cambridge, of which only one was in a cedar; two were in Spanish or mountain oaks and two in live oaks; four of these had more or less admixture of lichens, mosses, bits of dry leaves, and plant down in the bases, and feathers of quail, cardinal and other birds in the linings. The smallest nest in the series measures externally 21⁄2inches in diameter and 2 inches in height; it is very neatly and firmly woven.
Plumages.—Ridgway (1902) describes the juvenal plumage of the golden-cheeked warbler as follows: “Pileum, hindneck, back, scapulars, rump, and upper tail-coverts plain grayish brown or brownish gray; sides of head, chin, throat, chest, and sides pale brownish gray; rest of under part white, the breast very indistinctly streaked with pale gray; wings and tail essentially as in adults, but middle coverts with a mesial wedge-shaped mark of dusky.”
Apparently there is a partial postjuvenal molt early in the summer, which is similar to that of other wood warblers. This produces the first winter plumages, in which the sexes are recognizable and much like the respective adults at that season. In the young male the upper parts are streaked with olive-green and black, the upper tail coverts are margined with olive-green and gray, and the white tips of the median wing coverts have narrow, black shaft streaks instead of the dusky wedges seen in the juvenal coverts. Ridgway (1902) says of the young female: “Similar to the adult female but pileum, hindneck, back, scapulars, rump, and upper tail-coverts plain olive-green, or with very indistinct narrow streaks of dusky on pileum and back; throat and chest pale grayish (the feathers dusky beneath surface), the former tinged with yellow anteriorly; sides and flanks indistinctly streaked with dusky.”
I have seen no specimens showing a prenuptial molt, which is probably finished before the birds arrive in Texas. The first and subsequent nuptial plumages may be largely produced by wear, as the fall and winter plumages are much like those of spring birds, but are concealed by the tips and margins of the feathers. However, it would be strange if there were no prenuptial molt, especially in young birds.Young birds in first nuptial plumage can be recognized by the worn and faded wings and tail.
Eggs.—Four eggs make up the regular set for the golden-cheeked warbler, although sometimes only three and very rarely five are found. They are ovate to short ovate and have only a very slight lustre. They are white or creamy white, finely speckled and spotted with “bay,” “auburn,” or “chestnut,” and occasionally “argus brown,” intermingled with spots of “vinaceous drab,” “brownish drab,” or “light mouse gray.” They are generally finely marked, but sometimes eggs will have spots which are large enough to be called blotches, or even a few small scrawls of very dark brown. The markings are concentrated at the large end, where frequently a fine wreath is formed, or the speckles may be so dense as to almost obscure the ground; occasionally the markings are scattered over the entire egg. The measurements of 50 eggs average17.7by 13.1 millimeters; the eggs showing the four extremes measure18.9by 13.0, 17.8 by13.7, and15.6by12.4millimeters (Harris).
Young.—We have no information on incubation or on the care and feeding of the nestlings. Attwater (Chapman, 1907) has this to say:
The young birds out of the nest, which are being fed by the parents late in April and in May, are from early nests which have escaped destruction by “northers” on account of their sheltered positions and situations, and it is possible that then another nest is built and a second brood reared.* * *During June the family groups wander about together, chiefly in the cañons and along the lower hillsides, keeping together till the young are old enough to take care of themselves. While being fed by the parents the “twittering” of the young birds is continually heard, with the cautions “tick, tick” alarm notes of the female when enemies approach. Early in July they begin to scatter, as most of the young birds are then able to shift for themselves.
Food.—Very little has been mentioned regarding the food of this wood warbler beyond the fact that it seems to be mainly, if not wholly, insectivorous. Mr. Attwater (1892) says: “Upon examining the stomachs of a number of young birds which were being fed, I found they all contained (with other insects) a number of small black lice (Aphissp.) which I watched the old birds collecting from the green cedar limbs.”
Behavior.—Mr. Attwater wrote to Dr. Chapman (1907):
Like most of the same sex of other Warblers, the female of this species is very shy, and seldom noticed except when an intruder disturbs the nest or when feeding the young after leaving it, but the male Golden-cheeked Warbler is by no means a shy bird. He keeps continually flying from tree to tree in search of insects, and on fine days uttering his song at short intervals from early dawn until after sundown, and before nest building begins shows little alarm upon being approached. I have stood under a tree a number of times within five or six feet of a wandering male Golden-cheek, which appeared as pleased andinterested in watchingmeas I was in observing him. Seemingly he was desirous of assisting me to describe his song in my note-book, by very obligingly repeating it frequently for my special benefit.
Mr. Werner told Mr. Brewster (1879) that “their habits were similar to those ofD. virens; they were very active, always on the alert for insects, examining almost every limb, and now and then darting after them while on the wing.”
Voice.—The song evidently bears a resemblance to that of the black-throated green warbler in quality. Mr. Werner wrote ittsrr weasy-weasy tweah, and referred to the notes as soft. Mr. Attwater wrote to Dr. Chapman (1907): “It would be difficult to describe the Golden-cheek’s song with any real satisfaction. It varies somewhat, being uttered much more rapidly by some individuals than by others. At a distance only the louder parts are heard, so that it sounds quite different than when heard at close quarters. The hurried song might be given astweah, tweak, twee-sy, with some individuals introducing an extra note or two, and the slower or more deliberate styletwee-ah, eseah, eachy. After the young leave the nests the males gradually stop singing, and at this period sometimes only use a part of the regular song.”
George Finlay Simmons (1925) describes the song as “ventriloquistic, elusive, seeming to come from here, there, everywhere;ter-wih-zeee-e-e-e, chy, the first, second, and fourth notes short and soft, the third longest, most distinct, and with the shrill buzzingz-z-z-zquality of the Black-throated Green Warbler’s song.* * *Sung by male from conspicuous perch atop a small tree near nest and hidden female; heard commonly in spring in the Golden-cheek habitat; males gradually stop singing when young have left nest. Call, chirping in migration; female, a soft, scoldingcheck, check, checkortick, tick, uttered slowly, a note at a time.”
Enemies.—According to Dr. Friedmann (1929), the golden-cheeked warbler is “apparently a rather rare victim of the Dwarf Cowbird.” He mentions only three authentic cases.
Field marks.—The golden-cheeked warbler might at first glance be mistaken for a black-throated green warbler, but the upper parts in the adult male are deep black from crown to tail, instead of olive-green, and the under parts, except for the black throat, are white and not tinged with yellow. The female differs from the eastern bird in the same way.
Fall.—Golden-cheeked warblers do not remain on their breeding grounds very long and leave for their winter resorts in Mexico and Central America before the end of summer. Mr. Attwater told Dr. Chapman (1907) that "early in July they begin to scatter, as most of the young birds are then able to shift for themselves. By the middleof July most of the old males have stopped singing, and by the end of July old and young have disappeared from their usual haunts. I have noticed a few stragglers during the first two weeks in August, and all probably leave before September first.”
DISTRIBUTION
Range.—Texas to Nicaragua.
Breeding range.—During the breeding season the golden-cheeked warbler is confined to a few counties in south central Texas:Northto Kerr (Ingram and Kerrville) and Travis (Austin) Counties;southto Bexar (San Antonio) and Medina (Castroville) Counties; andwestto Real County (West Frio Canyon). It is probably not so narrowly confined as the definite records indicate. It has been recorded in summer, but with no indication of breeding, at Waco, Hunt, and Commerce.
Winter range.—Little is known of the golden-cheeked warbler in winter. At that season it has been found at Teziutlán, western Veracruz; Tactic, central Guatemala; and Matagalpa, central northern Nicaragua. On November 23, 1939, and January 8, 1940, a male was observed on the island of St. Croix, Virgin Islands. It has been observed in Tamaulipas and Nuevo León in March, probably on migration.
Migration.—The golden-cheeked warbler is an early migrant both in spring and fall. It has arrived at Kerrville, Tex., as early as March 5, and the majority of the birds have left by the middle of July; latest, Ingram, August 18.
Egg dates.—Texas: 29 records, April 1 to June 27; 10 records, April 11 to 24; 10 records, May 18 to 28 (Harris).
DENDROICA OCCIDENTALIS (Townsend)
HERMIT WARBLER
Plate 39
HABITS
This well-marked wood warbler lives in summer in the high coniferous forests of the west, from British Columbia southward to the southern Sierra Nevadas in California, and spends the winter in Mexico and Central America. This is another of those species discovered by J. K. Townsend along the Columbia River, of which he wrote to Audubon (1841): “I shot this pair of birds near Fort Vancouver, on the 28th of May, 1835. I found them flitting among the pine trees in the depth of a forest. They were actively engaged insearching for insects, and were frequently seen hanging from the twigs like Titmice. Their note was uttered at distant intervals, and resembled very much that of the Black-throated Blue Warbler,Sylvia canadensis.”
In northwestern Washington the hermit warbler is not common and is decidedly local in its summer haunts, being regularly found in certain favored regions and entirely absent in other somewhat similar localities. It is partial to a certain type of coniferous forest, and when one learns to recognize the proper environment he is quite likely to find it. D. E. Drown and S. F. Rathbun showed me some typical haunts of this warbler near Tacoma, where J. H. Bowles has found it nesting. This is level land covered with a more or less open growth of firs and cedars, the largest trees, giant Douglas firs, are somewhat scattered and tower above the rest of the forest, some reaching a height of 200 feet or more. As the warblers spend most of their time in the tops of these great trees and are very active, it is difficult to identify them even with a good glass, and still more difficult to follow them to their nests.
Chester Barlow (1901) says that in the central Sierra Nevada, in California, “the hermit warbler is pre-eminently a frequenter of the conifers, although it feeds in the bushes and black oaks in common with other species.” In the Yosemite region, according to Grinnell and Storer (1924), “the Hermit Warbler is a bird of the coniferous forests at middle altitudes. Pines and firs afford it suitable forage range and safe nesting sites. The birds keep fairly well up in the trees, most often at 20 to 50 feet from the ground. The Hermit may thus be found in close association with the Audubon Warbler, although the latter ranges to a much greater altitude in the mountains.”
Spring.—Dr. Chapman (1907), outlining the migration of the hermit warbler, says that it “enters the United States in April being reported from Oracle, Arizona, April 12, 1899, and the Huachuca Mountains, Arizona, April 9, 1902. Records of the earliest birds seen in California are Campo, April 27, 1877, and Julian, April 25, 1884. A Hermit Warbler was noted at Burrard Inlet, British Columbia, April 20, 1885.” Swarth (1904) says that the first arrivals in the Huachucas “appeared in the very highest parts of the mountains, but a little later they could be found in all parts of the range, and on April 17, 1902, I saw a few in some willows near the San Pedro River.” Mrs. Amelia S. Allen’s notes from the San Francisco Bay region, give dates of arrival from April 24 to May 10. In northwestern Washington, according to Bowles (1906), “the hermits make their first appearance early in May and the fact is only to be known thru their notes; for they frequent the tops of the giant firs which cover large sections of our flat prairie country.”
Nesting.—The first undoubted nests of the hermit warbler were found by C. A. Allen in Blue Cañon, California, two in 1886 and one about eight years previously, about which he wrote to William Brewster (1887): “All three nests were similarly placed;—in ‘pitch pines,' from twenty-five to forty feet above the ground, on thick, scraggy limbs, where they were so well concealed that it would have been impossible to find them except by watching the birds, as was done in each instance.” One of these nests held two eggs on June 4, but they were destroyed before they could be collected; the other two nests contained three young each. One of the nests with three young was sent to Brewster, who writes:
The nest with young, taken June 7, 1886, is now before me. It is composed of the fibrous stalks of herbaceous plants, fine dead twigs, lichens (Evernia vulpina), and a little cotton twine, and is lined with soft inner bark of some coniferous tree and fine long hairs, apparently from the tail of a squirrel. The bright, yellowEvernia, sprinkled rather plentifully about the rim, gives a touch of color to the otherwise cold, gray tone of the exterior and contrasts agreeably with the warm, reddish-brown lining. Although the materials are coarse and wadded, rather than woven, together, the general effect of this nest is neat and tasteful. It does not resemble any other Warbler’s nest that I have seen, but rather recalls the nest of some Fringilline bird, being perhaps most like that of the Lark Finch. It measures externally 4.50 inches in width by 2 inches in depth. The cavity is 1.25 inches deep by 2.50 inches wide at the top. The walls at the rim average nearly an inch in thickness.
Chester Barlow (1901), who has had considerable experience with the nesting of the hermit warbler in the central Sierra Nevada, refers to the records up to that time as follows:
On June 10, 1896, Mr. R. H. Beck collected a nest and four eggs from a limb of a yellow pine 40 feet up, near the American River at 3,500 feet altitude. The nest was reached by means of a ladder carried a long distance up the mountain. (SeeNidologist, IV, p. 79). On June 14, 1898, I had the good fortune to discover a nest opposite the station at Fyffe, it being built at the end of a small limb of a yellow pine 45 feet up. The nest was located by searching at random and contained four eggs about one-fourth incubated. This nest was described at length inThe Auk(XVI, pp. 156-161.)* * *While walking through the timber at Fyffe on June 8, 1899, Mr. H. W. Carriger came upon a nest of this species but 21⁄2feet up in a cedar sapling. It contained four eggs, advanced in incubation. (See CONDOR I, pp. 59-60). A nest containing young about four days old found by Mr. Price’s assistant at Fyffe on June 11, 1897, was placed twelve feet up near the top of a small cedar, next to the trunk and well concealed. Thus it is probable that Fyffe has afforded more nesting records of this species than has any other part of the state.
Of the nest described inThe Auk, Barlow (1899) says:
The nest was 45 feet from the ground in a yellow pine, built four feet from the trunk of the tree on an upcurved limb 18 inches from the end.* * *The nest is not fastened to the limb, resting merely upon the limb and pine needles and is wider at the bottom than at the top, its base measuring four inches one way and three inches the other. It is very prettily constructed, the bottom layerbeing of light grayish weed stems, bleached pine needles and other light materials held securely together by cobwebs and wooly substances. The nest cavity is lined with strips of red cedar bark (Libocedrus) and the ends, instead of being woven smoothly, project out of the nest. The inner lining is of a fine brownish fiber resembling shreds of soap-root. The composition of the nest gives it a very pretty effect.
J. H. Bowles (1906) found a nest in northwestern Washington on June 11, 1905, “in a grove of young hundred-foot firs near a small swamp.” The female sat so close that he was obliged to lift her from the nest with his hand—
and she then flew only a few feet where she remained chipping and spreading her wings and tail.* * *The nest was placed twenty feet from the ground in a young fir, and was securely saddled on a good sized limb at a distance of six feet from the trunk of the tree. It is a compact structure composed externally of small dead fir twigs, various kinds of dry moss, and down from the cottonwood flowers, showing a strong outward resemblance to nests ofD. auduboni. But here the likeness between the two is at an end; for the lining consists of fine dried grasses, and horsehair, with only a single feather from the wing of a western bluebird. The measurements are, externally, four inches in diameter and two and three-quarters inches deep; internally, two inches in diameter by one and a quarter inches deep.
A nest in the Thayer collection in Cambridge was collected by O. W. Howard “70 feet above ground, near the end of a limb of a yellow pine, in a bunch of needles,” in Tulare County, Calif. Gordon W. Gullion tells me of an Oregon nest that was “about 125 feet above the ground.”
Eggs.—The hermit warbler lays 3, 4, or 5 eggs to a set; 5 are apparently not rare. Bowles (1906) says of his 5 eggs: “They have a rather dull white ground with the slightest suggestion of flesh color, heavily blotched and spotted with varying shades of red, brown and lavender.* * *I think they may be considered the handsomest of all the warblers’ eggs.” The 4 eggs in the Thayer collection in Cambridge are ovate, with a very slight lustre. They are creamy white, finely speckled and spotted with “chestnut” and “auburn,” with intermingling spots of “light brownish drab.” The markings are concentrated at the large end, forming a broad, loose wreath. The measurements of 50 eggs average 17.0 by 13.1 millimeters; the eggs showing the four extremes measure18.0by 13.4, 17.0 by13.7,15.2by 12.7, and 16.3 by11.8millimeters (Harris).
Young.—We have no information on the incubation of the eggs, nor on the care and development of the young.
Plumages.—I have examined the nestlings sent to Brewster by C. A. Allen; they are about two-thirds fledged on the body and wings; the heads still show the long natal down, “hair brown” in color; the feathers of the back are “olive brown”; the wings are “clove brown,” withtwo narrow, white wing bars, faintly tinged with pale yellow; the breasts and sides are pale “hair brown” to “light grayish olive”; and the rest of the under parts are yellowish white. A young bird in fresh plumage, collected July 1, is probably in full juvenal plumage; its body plumage is similar to that of the nestlings, but there is some yellow on the forehead and throat, and the sides of the head and neck are decidedly yellow; however, this may be a bird that has assumed its first winter plumage at an unusually early date.
In first winter plumage, young birds of both sexes are much like the adult female at that season, mainly grayish olive-green above, with black streaks concealed or absent; forehead, sides of the head, and chin pale yellow; and the rest of the under parts buffy white, the sides browner. The broad, white tips of the lesser wing coverts have a black shaft streak or wedge, apparently characteristic of this plumage. There is probably a prenuptial molt involving much of the head and body plumage and the wing coverts, but the dull juvenal wings are retained until the next molt.
The complete postnuptial molt occurs in July and August. The fall plumages of both sexes are like the spring plumages, but the clear blacks and yellows are largely concealed by olive above and by buffy below.
Food.—The only item I can find on the food of the hermit warbler is the following short statement by Bowles (1906): “Their food consists of small spiders, caterpillars, tiny beetles, and flying insects which they dart out and capture in a manner worthy of that peer of flycatchers the Audubon warbler.”
Behavior.—The most marked trait of the hermit warbler is its fondness for the tree tops, spending much of its time in the tops of the tallest firs, often 200 feet or more above the ground, where it is very active and not easy to follow. But it builds its nest at lower levels, and often comes down to forage in the lower branches, in smaller trees and even in the underbrush, where it is not particularly shy and can be easily approached. It is a close sitter while incubating; Bowles had to lift one off its nest.
A hermit warbler watched by Miss Margaret W. Wythe, in Yosemite Valley, “was foraging in the upper parts of the trees and never came to the lower branches. Starting from near the trunk of a pine it would work out to the tip of one branch before going to another. Its demeanor while foraging was much more deliberate than that of any of the other warblers” (Grinnell and Storer, 1924).
Voice.—Rathbun (MS.) writes: “The song is quite strong, can be heard a considerable distance, and when given in full consists of five or six notes. The first note, rather faint, rises and then falls, with a slight accent at its close; if one is quite close to the singer, the notehas a light lisping sound. This note is followed by another, similar but stronger and more prolonged. Then come three or four short, clear notes quickly given, the song ending with a prolonged rising one that closes sharply. Our interpretation of the song would bezweeo-zweeo-zwee-zwee-zwee-zweeck. Whenever an additional note is given, it is of the intermediate kind. One or two of these notes are, to us, suggestive of some heard in the song of Townsend’s warbler. The song is quite rapidly sung in an energetic way, being very distinctive and is pleasing. It resembles the song of no other warbler in the region.”
Bowles (1906) says that the song of the hermit warbler “consists of four distinct notes, as a rule, and is described aszeegle-zeegle, zeegle-zeek, uttered somewhat slowly at first but ending rather sharply.” Barlow (1899) states that “though not loud it would penetrate through the woods quite a distance and very much resembledtsit, tsit, tsit, tsit, chee chee chee, the first four syllables being uttered with a gradual and uniform speed, ending quickly with thechee chee chee.” Grinnell and Storer (1924) write:
The song of the male Hermit Warbler, while varying somewhat with different individuals, is sufficiently distinct from that of the other warblers of the region to make possible identification by voice alone. The song is most nearly like that of the Audubon Warbler but usually not so clear or mellow. A male bird observed at Chinquapin seemed to sayseezle, seezle, seezle, seezle, zeek, zeek; just that number of syllables, over and over again. The quality was slightly droning, but not so much so as that of the Black-throated Gray Warbler. Another song, clearer in quality, heard in Yosemite Valley, was writtenter´-ley, ter′-ley, ter´-ley, sic´, sic´, thus much more nearly like the song of the Audubon Warbler. Other transcriptions ranged between these two as to timbre. A rendering set down at Glacier Point June 16, 1915, was as follows:ser-weez´, ser-weez´, ser-weez´, ser´, ser´. The marked rhythm throughout, and the stressed terminal syllables, are distinctive features of the Hermit’s song. The call note is a moderatechip.
Writing of warbler songs of early dawn, Dawson (Dawson and Bowles, 1909) indulges in the following flowery praise of the hermit’s sing: “There is Audubon with his hastening melody of gladness. There is Black-throated Gray with his still drowsy sonnet of sweet content. Then there is Hermit hidden aloft in the shapeless greenery of the under-dawn—his note is sweetest, gladdest, most seraphic of them all,lilly, lilly, lilly, leê-oleet. It is almost sacrilege to give it form—besides it is so hopeless. The preparatory notes are like the tinkle of crystal bells, and when our attention is focused, lo! the wonder happens, the exquisite lilt of the closing phrase,leê-oleet.”
Field marks.—The yellow head, the black throat, the dark back, and the white, unmarked under parts will distinguish the male in spring. The head of the female, of young birds, and of fall birds is also moreor less yellowish and the back is more olivaceous. The two white wing bars are also common to several other species. Its song is said to be distinctive.
Fall.—The fall migration of the hermit warbler begins early. Bowles (1906) says that, in Washington, “about the middle of July both young and old assemble in good-sized flocks and frequent the water holes in the smaller growths of timber. At such times I have never seen them associating with any other kinds of birds.” W. W. Price wrote to Mr. Barlow (1901) of the migration in the Sierra Nevada:
The adults are very rare during June and July in the neighborhood of my camp at Silver Creek, but late in July and early in August a migration of the young birds of the year takes place and the species is very abundant everywhere in the tamaracks from about 6000 to 8000 feet. A hundred or more may be counted in an hour’s walk at my camp, 7000 feet, on Silver Creek. They are very silent, uttering now and then a ‘cheep,’ and always busy searching among the leaves and cones for insects. Among some fifty collected in the first week in August, 1896, there were only two or three adults. The young males have the most coloring, but they in no way approach adult plumage. These great flights of the hermit warbler are intermingled with other species, Hammond flycatcher, Calaveras and lutescent warblers, Cassin vireo, and sometimes Louisiana tanagers and red-brested nuthatches. Each year the flight has been noted, it comes without warning of storm or wind, and after a few days disappears to be seen no more.
In the Huachuca Mountains of Arizona, according to Swarth (1904), “they reappeared in August, but at this time were seen only in the pines above 8500 feet. It is rather singular, and in contradiction to the idea that in the migrations the old birds go first in order to show the way, that the first secured in the fall was a young female, taken August 7th. The young birds then became very abundant, and on August 14th the first adult female was taken; and not until August 19th was an adult male seen. The adults then became nearly as abundant as the juveniles, and both together were more numerous than I have ever seen them in the spring, on several occasions as many as fifteen to twenty being seen in one flock.”
Winter.—Dr. Skutch writes to me: “The hermit warbler is a moderately abundant winter resident in the Guatemalan highlands, found chiefly between 5,000 and 10,000 feet above sea level, but ranging downward to about 3,500 feet on the Pacific slope and possibly somewhat lower on the Caribbean slope, where pine forests push down into the upper levels of the Tropical Zone. These treetop birds are usually found in the mixed flocks of small birds, of which Townsend’s warblers form the predominant element. During the early part of their sojourn in Guatemala, I sometimes saw two, three, or more hermits in the same flock; but in February and March, there was asa rule only one. In 1933, I saw the last of these warblers on the Sierra de Tecpán on March 29, and recorded the first fall arrival on September 13, when four individuals were seen.”
DISTRIBUTION
Range.—Western North America from Puget Sound to Nicaragua.
Breeding range.—The hermit warbler breedsnorthto northwestern Washington (Lake Crescent and Tacoma).Eastto the Cascades of Washington (Tacoma); Oregon (Prospect); and the Sierra Nevada in California (Meadow Valley, Pinecrest, Yosemite Valley, Taylor Meadow, and the San Bernardino Mountains).Southto the San Bernardino Mountains and La Honda.Westto the Pacific coast from central western California northward (La Honda, Cahto, and Garberville); western Oregon (Kerby and Tillamook); and northwestern Washington (Lake Crescent).
Winter range.—The hermit warbler has been found in winternorthto central Mexico (Taxco, Cuernavaca, and Mexico City).Eastto Mexico City and central Guatemala (San Gerónimo and Alotepeque).Southto southern Guatemala (Alotepeque); probably farther south since specimens have been taken at Los Esesmiles, El Salvador, and Metagalpa, Nicaragua.Westto western Guatemala (Alotepeque, Tecpán, and Momostenango); western Oaxaca (La Parada); and northern Guerrero (Taxco).
The hermit warbler has been taken three times in January in central western California (San Gerónimo and Point Reyes, Marin County; and Pacific Grove, Monterey County).
Migration.—Late dates of spring departure from the winter home are: Guatemala—Tecpán, March 29. Sonora—Rancho la Arizona, May 8. Arizona—Huachuca Mountains—May 28.
Early dates of spring arrival are: Tampico—Galindo, March 19. Coahuila—Sierra de Guadeloupe, April 20. Arizona—Oracle, April 12. California—Witch Creek, April 10. Washington—Tacoma, April 25.
Late dates of fall departure are: Washington—Edwards, October 19. California—Monterey, October 20. Arizona—Santa Catalina Mountains, September 29. Tamaulipas—Guiaves, October 7.
Early dates of fall arrival are: California—Berkeley, July 9. Arizona—Graham Mountains, July 30. New Mexico—Animas Peak, August 3. Michoacán—Tancitaro, August 16. Guatemala—Tecpán, September 13.
Casual records.—Specimens of the hermit warbler have been collected in the Huachuca Mountains in Arizona on June 16, 1894; at Basin in the Chisos Mountains in Texas on May 3, 1935; and near Cambridge, Minn., on May 3, 1931.
Egg dates.—California: 10 records, May 14 to June 25; 6 records, June 3 to 14, indicating the height of the season.
Washington: 3 records, June 5 to 11 (Harris).
DENDROICA CERULEA (Wilson)
CERULEAN WARBLER
Plate 39
HABITS
This heavenly-blue wood warbler was first introduced to science, figured, and named by Wilson in the first volume of his American Ornithology. Only the male was figured and described from a specimen received from Charles Willson Peale and taken in eastern Pennsylvania. The female was not known until Charles Lucien Bonaparte described it in his continuation of Wilson’s American Ornithology. Strangely enough the discovery of this specimen was also made by a member of the famous Peale family, Titian Peale, the bird having been taken in the same general region, on the banks of the Schuylkill, August 1, 1825. Audubon met with it later, but was almost wholly wrong in what he wrote about it, though his plate is good.
The species is now known to occupy a rather extensive breeding range located mainly west of the Alleghenies and east of the Great Plains from southern Ontario and central New York southward to the northern parts of some of the Gulf States and Texas. It is, however, decidedly local in its distribution over much of this range.
This warbler, a bird of the tree-tops in heavy deciduous woods, where its colors make it difficult to distinguish among the lights and shadows of the lofty foliage and against the blue sky, is well named cerulean! In his notes from central New York, Samuel F. Rathbun writes: “The type of growth to which the cerulean warbler is partial appears to be the rather open forests in the lowlands and often along some stream. During the nesting season, it will not be found to any extent in the better class of hardwood trees of the uplands; in fact, this warbler shows a strong liking for areas where large elms and soft maples and black ash are the dominant trees.” Verdi Burtch wrote to Dr. Chapman (1907) that near Branchport, N. Y., this warbler is “locally abundant in mixed growths of oak and maple with a few birch and hickory.” In other portions of its range, it is found in mixed woods of maples, beech, basswood or linden, elm, sycamore, or oaks. Frank C. Kirkwood (1901) found that, in Maryland, “the species has a decided preference for high open woods clear of underbrush.* * *The trees are principally chestnuts, with oaks, hickorys, tulip trees, etc.”
Spring.—The main migration route of the cerulean warbler is through the Mississippi Valley, from the Alleghenies westward; it is rare in the Atlantic States, especially the more southern ones, and hardly more than casual in Florida and the West Indies. It enters the United States, in Texas and Louisiana, in April, and reaches its breeding grounds in the interior early in May.
Rathbun (MS.) says of the spring migration in central New York: “The cerulean warbler arrives in this region about the middle of May, its coming being announced by its song. With rare exceptions, it is not found in the spring migration with other warblers and it appears to move in very small groups or singly; even in the large springtime movements of warblers known as ‘waves,’ some of the birds of which remain while others pass through the region, I have observed very few cerulean warblers. Not much time elapses after its arrival before mating takes place and nest building begins.”
Nesting.—The earlier ornithologists knew nothing about the nesting habits of the cerulean warbler; Audubon’s description of its nest was entirely erroneous, and it was about 50 years after the bird was discovered that its nest was reported. This is not strange, as the nest is not easy to find and still more difficult to secure. Rathbun (MS.) writes in his notes: “During our stay in New York State, we found only three of its nests, because they were rather difficult to locate. We found the first at a height of 55 feet in a little cluster of small, twig-like branches growing on the side of a feathered elm; these clusters were close enough together to be of great use in climbing the tree, which was at least 3 feet in diameter. The nest was discovered by seeing the bird fly into the cluster. Within the next week a second nest was found by watching the female bird; it was at a height of 45 feet in a very small, flat crotch of a soft maple. The third nest was at a height of about 30 feet.
“The nests were identical in all respects except as to shape, which varied because of its situation. Each was nicely made but not unusual in appearance. The material used was almost wholly the fine strips of the grayish bark of small weed stalks, neatly interwoven. Each was smoothly and beautifully lined with the fresh stems of ground mosses of a brownish red color, which contrasted nicely with the gray outer material. Of great interest was the smoothness with which the material was woven in.”
Burtch wrote to Dr. Chapman (1907) that near Branchport, N. Y., where the bird is locally common, “the nest is usually placed on a horizontal branch or drooping branch of an elm, ranging from twenty-five to sixty feet from the ground, and from four, to fifteen, or eighteen feet from the body of the treeover an opening.”
W. E. Saunders (1900) reports eight nests found in southern Ontario; two of these were in oaks, 20 and 23 feet up, two in maples,30 and 35 feet from the ground, and four in basswoods (lindens), from 17 to 50 feet above ground. He gives the measurements of three nests; they measured externally from 13⁄4to 2 inches in height and 23⁄4inches in diameter; internally they varied from7⁄8to 1 inch in depth and from 17⁄8to 13⁄4inches in diameter. He remarks: “A feature that interested me very much was the extreme shallowness of the nests; all the other warblers with which I am acquainted building a comparatively deep nest, and the query arises, Does the bird build a shallow nest because it places it on a substantial limb, or does it place it on a substantial limb because its nests are shallow? The attachment of the nest, also, is exceedingly frail, and I am inclined to think that few of these nests would remain in position long after the young had left.”
A nest found by Kirkwood (1901) in Baltimore County, Md., is described as follows: “The nest is made of brown bark fibre, with some fine grass stems among it, and is finished inside with a few black horse-hairs. Outside it is finished with gray shreds of bark, spider web, and a few small fragments of newspaper that had been water-soaked.* * *As the branch sloped, one part of the rim is within3⁄4of an inch of it, while the opposite part is 13⁄4inches above it, the material comes down on one side of branch to 21⁄4inches below the rim. On this side a tiny twig arches out from branch and extending to the rim is embedded in the nest, and the leaves which grew from its top shaded the nest.” The nest was 48 feet and 6 inches up from the ground and 15 feet out from the trunk of a tulip tree, with no other limb between it and the ground.
A neat little nest before me is made of materials similar to those mentioned. It is lined with the reddish brown flowering stems of mosses smoothly woven with other very fine brownish fibres into a compact rim, and it is decorated externally with various brown and gray lichens and mosses. Other nests have been reported in sycamores, beeches, rock maples, sugar maples, and white oaks.
Eggs.—The cerulean warbler lays from 3 to 5 eggs, usually 4. They are ovate to short ovate and have a slight luster. The ground color is grayish white, creamy white, or even very pale greenish white, and they are speckled, spotted or blotched with “bay,” “chestnut,” or “auburn,” intermingled with spots of “light brownish drab,” or “brownish drab.” Some eggs have spots scattered all over the surface, but usually they are concentrated at the large end, where a loose wreath is formed. Generally the eggs are finely marked, but occasionally are quite heavily blotched. The measurements of 50 eggs average 17.0 by 13.0 millimeters; the eggs showing the four extremes measure17.9by 13.0, 17.0 by13.7,16.0by 12.4, and 17.2 by12.0millimeters (Harris).
Young.—The period of incubation seems to be unknown, and we have no information on the care and development of the young. Incubation is said to be performed by the female alone, but both parents assist in feeding the young. After the young are out of the nest, they may be seen travelling through the woods in family parties with their parents. There seems to be no evidence that more than one brood is raised in a season.
Plumages.—Ridgway (1902) describes the young cerulean warbler in nestling (juvenal) plumage as “above uniform brownish gray (deep drab gray), the pileum divided longitudinally by a broad median stripe of grayish white; sides of head (including a broad superciliary stripe) and entire under parts white; a narrow postocular stripe of deep drab gray; wings as in adults, but edgings greenish rather than bluish.”
The first winter plumage is assumed by a partial postjuvenal molt, involving the contour plumage and the wing coverts, but not the rest of the wings nor the tail. Dr. Dwight (1900) describes the young male in this plumage as “above, deep bice-green, partly concealing cinereous gray which is conspicuous on the rump and upper tail coverts, the latter and the feathers of the back often black centrally. The wing coverts with bluish cinereous gray edgings; two wing bands white, faintly tinged with canary-yellow. Below, white, strongly washed except on the chin, abdomen and crissum with primrose-yellow, the sides and flanks streaked obscurely with dull black. Superciliary line primrose-yellow; lores and orbital regions whitish; a dusky transocular streak.”
The first nuptial plumage is acquired by a partial prenuptial molt “which involves much of the body plumage and wing coverts, but not the rest of the wings nor the tail. The grayish cerulean blue, the black streaks on the back and the white wing bands are acquired; below, the plumage is white with a narrow bluish black band on the throat and the sides distinctly streaked. Young and old become practically indistinguishable, except by the duller wings and tail of the juvenal dress.”
The adult winter plumage is acquired by a complete postnuptial molt in July, which he says “differs from first winter in being much bluer and whiter, the wings and tail blacker and the edgings a bluer gray. Resembles the adult nuptial, but rather grayer on the back and the throat band incomplete.” The adult nuptial plumage is acquired by a partial-prenuptial molt as in the young bird.
He says of the plumages of the female: “The plumages and moults correspond to those of the male. In juvenal plumage the edgings of the wings and tail are greener tinged than those of the male. In first winter plumage the green above is duller and the black of the backand tail coverts is lacking; below there is more yellow and the side streaks are obscure. The first nuptial plumage is acquired by a moult limited chiefly to the head and throat which become bluer and whiter respectively. Later plumages are brighter, but green always replaces the blue of the male.”
Food.—No thorough study of the food of the cerulean warbler seems to have been made, but it is known to be insectivorous, foraging among the foliage, twigs, branches, and even on the trunks of trees. It is an expert fly catcher, darting out into the air for flying insects. A. H. Howell (1924) says that “examination of 4 stomachs of this species taken in Alabama showed the food to consist of Hymenoptera, beetles, weevils, and caterpillars.” Professor Aughey (1878) observed this warbler catching locusts in Nebraska.
Behavior.—S. Harmsted Chubb (1919) describes the behavior of the cerulean warbler as follows:
A bird more difficult to observe I have rarely if ever met with. His life seemed to be confined almost entirely to the tops of the tallest deciduous trees, where he would generally feed, with apparent design, on the side most remote from the would-be observer, exhibiting a wariness not expected on the part of a warbler, and finally leaving the tree, the first intimation of his departure being a more distant song. He never remained in the same tree top more than eight or ten minutes at a time and yet rarely ventured out of hearing distance from the center of his range. Fortunately, he would sometimes take a perch on a bare twig and sing for several minutes, but the perch was always high and generally with the sky as a poor background for observation. Had it not been for the almost incessant singing, being heard almost constantly from daybreak until nearly dark, the task of identification would have seemed hopeless.
Voice.—Aretas A. Saunders writes to me: “I have but six records of the song of this bird. There is probably more variation in the song than these records show, for all six are much alike. The song consists of four to eight notes, of even time and all mainly on one pitch, followed by a trill about a tone higher, the latter, in all of my records, pitched on C‴′. The first notes, in one of my records, are upward slurs, and in two others the first note of the group slurs upward, but in all of the others all of the notes are of even pitch and not slurred. The pitch varies from G‴ to C‴′. The songs are undoubtedly between one and two seconds in length, but I had no stop watch at the time, so did not time them. The song is rather loud and not particularly musical. In form the song is much like that of the Blackburnian warbler, but the loudness, different quality, and lower pitch distinguish it.”
Francis H. Allen (MS.) writes the song as “wee wee wee wee bzzz, heard many times without any apparent variation.” This was somewhat different from the song of a cerulean I heard, which had a “chippy” beginning that suggested the song of a yellow palm warbler,and also that of the parula warbler. Rev. J. J. Murray writes to me from Virginia: “The songs of the parula and cerulean in this section are very similar, but not difficult to distinguish. The pattern is reversed in the two; the parula’s song is ‘bzz, bzz, bzz, trill', while that of the cerulean is a ‘trill, trill, trill, bzz'. The cerulean’s song can be expressed by the phrase 'Just a little sneeze.'” A. D. DuBois tells me that “the beginning of the song is similar to that of the redstart, but it ends with a fine, ‘wiry,’ grasshopper-like trill, ascending in pitch and drawn out to nothing at the end.” Mr. Chubb (1919) describes two songs of the cerulean warbler as follows:
The musical exercises of the bird consisted of an alternation of two distinctly different songs, so different indeed that until the bird was caught in the act we never for a moment suspected a single authorship. One song suggested slightly that of the Magnolia Warbler but rather softer, four syllables, though not quite so well defined as in the Magnolia. The other, for want of something better, might be compared with the song of the Parula Warbler, a short buzzing trill rising in the scale, much louder and less lispy than the song of the Parula. The songs were each of about one second duration, rendered approximately eight or ten times per minute. Altogether the performance was quite musical, in sweetness far above the average warbler song. These two songs were generally alternated with clock-like regularity, though occasionally the bird preferred to dwell upon one or other of his selections for the greater part of the day.
Kirkwood (1901) says: “It also gives its song in a low tone as if it whispered it, and unless the bird is carefully watched the observer might be led to believe that he heard a second bird singing in the distance. I have watched a bird sing thus between each regular song, at other times it would not give it at all, or only occasionally, while on two or three occasions I heard it given for quite a while to the exclusion of the regular song, and quite often have heard it given two or three or even more times in succession between regular songs.” He has heard the cerulean warbler singing through July and until the middle of August; on August 19, he heard them singing “immature or imperfect (?) songs.”
Enemies.—The cerulean warbler is a rather uncommon victim of the eastern cowbird; not more than 10 cases seem to have been recorded.
Field marks.—No other American wood warbler has a similar shade of heavenly blue on its back as the male cerulean; its under parts are pure white, relieved by a narrow black necklace, and it has two white wing bars. Females, young birds, and even fall males are similar, and are tinged with blue above and with pale yellow below, with a whitish or yellowish line over the eye. In this plumage they resemble the young parula warbler, but the latter is much deeper yellow on the breast and has no line over the eye.
Fall.—Rathbun says in his notes from central New York: “When July comes the warblers will be found quite widely dispersed in anysort of forest, because they are now moving through the country in little family groups. Now and then will be heard snatches of the spring song. This is but preparatory for their departure from the region, which takes place in the latter part of August; we have never seen this warbler after the first week in September.”
Professor Cooke (1904) writes:
The cerulean warbler is a rare migrant in the States along the Atlantic coast, though it has been noted in the Carolinas, Georgia, and Florida. In northeastern Texas and Louisiana it is not uncommon. Its main route of migration seems to cross the Gulf of Mexico chiefly from Louisiana and Mississippi. The species is one of the first to start on the southward migration. By the middle of summer it has reached the Gulf coast and is well on its way to its winter home. At Beauvoir and Bay St. Louis, on the coast of Mississippi, it has appeared in different years on dates ranging from July 12 to 29. For a few days it is common, attaining the height of its abundance about the first week in August. It then passes southward so rapidly that Cherrie was able to record its presence on August 24, 1890, at San José, Costa Rica. By November it reaches central Ecuador. Though the bulk of the birds perform their migration at this early date, some laggards remain behind until late in the season.
Dr. A. F. Skutch tells me it is “exceedingly rare in Guatemala.* * *I have never seen the cerulean warbler in Central America.” In Ecuador, I found a male in the Pastaza Valley, at an altitude of about 4,000 feet, on October 15, 1939. Two days later this warbler had become fairly common in this locality, and I saw several individuals.
Winter.—Says Professor Cooke (1904): “The cerulean warbler is chiefly found in winter in South America from Panamá south to Perú, in which country it seems to have its center of abundance. In western Perú Jelski (Taczanowski, Proc. Zool. Soc. London, p. 508, 1847) found it common at Monterico and other places in the mountains east of Lima at 10,000 to 13,000 feet elevation, always in wandering flocks, which were sometimes quite large and contained both old and young birds.”
DISTRIBUTION
Range.—North and South America from southern Canada to Perú and Bolivia.
Breeding range.—The cerulean warbler breedsnorthto southern Minnesota (Minneapolis); southern Wisconsin (Barahoo Bluffs, Madison, and Racine, possibly as far north as New London); central Michigan (Saginaw, Locke, and Detroit); southern Ontario (Thedford, Plover Mills, Warren, and Delta; perhaps Manotick); and southern New York (Lockport, Rochester, Ithaca, Santa Cruz Park, and Wappingers Creek, Dutchess County).Eastto southeastern New York (Dutchess County); rarely northeastern Maryland (Towson); southwestern Delaware (Seaford); western Virginia (Charlottesvilleand Natural Bridge); western North Carolina (Morganton and Pink Beds); and northern Georgia (Lumpkin County and Atlanta).Southto north-central Georgia (Atlanta); south-central Alabama (Autaugaville and Greensboro); northern Louisiana (Monroe and Caddo Lake); and northern Texas (Texarkana and Dallas).Westto northeastern Texas (Dallas); northeastern Oklahoma (Copan); southeastern Kansas (Independence); eastern Nebraska (Omaha and Pilgrim Hill, Dakota County); western Iowa (Sioux City); and southern Minnesota (Minneapolis).
Winter range.—The winter home of the cerulean warbler is northwestern South America, in the valleys of the Andes from central Colombia (Antioquia, Medellín, and Bogotá) through Ecuador (Río Napo, Sara-yacu, and the Pataza Valley); to southern Perú (Huachipa and Lima). It has also been found occasionally or accidentally in central northern Venezuela (Rancho Grande); and in western Bolivia (Nairapi and Tilotilo near La Paz). Casual in winter or migration in the Cayman Islands and western Cuba.
Migration.—Late dates of spring departure are: Perú—Huambo, March 15. Ecuador—near San José, March 31. Colombia—Buena Vista, March 4. Florida—Pensacola, April 26. Texas—Austin, April 30.
Early dates of spring arrival are: Florida—Dry Tortugas Island, March 23. Alabama—Greensboro, March 26. Georgia—Atlanta, April 13. South Carolina—Clemson (College), April 21. North Carolina—Asheville, April 23. Virginia—Charlottesville, April 13. West Virginia—Wheeling, April 23. Pennsylvania—McKeesport, April 23. New York—Corning, April 25. Louisiana—Grand Isle, March 27. Arkansas—Tillar, April 6. Tennessee—Athens, April 4. Kentucky—Eubank, April 5. Illinois—Olney, April 18. Indiana—Bloomington, April 11. Michigan—Bay City, April 26. Ohio—Toledo, April 20. Ontario—Hamilton, April 25. Missouri—St. Louis, April 12. Iowa—Hillsboro, April 18. Minnesota—Faribault, April 29. Texas—Victoria, March 17. Oklahoma—Copan, March 27. Kansas—Independence, April 24.
Late dates of fall departure are: Ontario—Point Pelee, September 5. Michigan—Detroit, September 5. Ohio—Ashtabula, September 27. Indiana—Whiting, October 4. Illinois—Chicago, September 28. Kentucky—Versailles, September 4. Tennessee—Athens, September 27. Mississippi—Gulfport, September 17. Oklahoma—Copan, October 1. Texas—Austin, September 27. New York—New York, September 18. Pennsylvania—Berwyn, September 29. North Carolina—Raleigh, September 16. Georgia—Augusta, September 16. Alabama—Birmingham, September 21. Florida—Pensacola, September 18. Costa Rica—San José, October 24.
Early dates of fall arrival are: Texas—Austin, July 20. Mississippi—Beauvoir, July 12. Virginia—Sweet Briar, July 20. Georgia—Athens, July 28. Florida—Pensacola, July 23. Costa Rica—Villa Quesada, August 23. Ecuador—Río Oyacachi, August 10. Perú—Huachipa, October 3.
Casual records.—The majority of the cerulean warblers found east of the Allegheny Mountains might be considered as casual. All records for New England should as yet be so considered, though the species has increased in eastern New York in recent years. About 10 individuals have been recorded in Massachusetts; two in Rhode Island, and one in New Hampshire. On June 2, 1924, one was collected at Whitewater Lake, in southwestern Manitoba, the farthest north that the species has been found. There are two records for North Dakota; one near Jamestown on May 28, 1931, and another near Minot on May 24, 1937. A cerulean warbler was recorded near Denver, Colorado, on May 17, 1883, and a specimen collected on September 2, 1936, on Cherry Creek in Douglas County. A bird “observed at the Mimbres during the latter part of April” is the only record for New Mexico. On October 1, 1947, a specimen was collected at the southeastern edge of the Salton Sea in California; and on October 2, 1925, a specimen was collected near La Grulla in the Sierra San Pedro Mártir, Baja California.
Egg dates.—Ontario: 3 records, June 2 to 13.
New York: 22 records, May 29 to July 9; 15 records, June 1 to 4.
Pennsylvania: 5 records, May 16 to 26.
DENDROICA FUSCA (Muller)
BLACKBURNIAN WARBLER
Plates 40, 41
HABITS
Bagg and Eliot (1937) give the following account of the history of the naming of the Blackburnian Warbler:
Some time in the later eighteenth century, a specimen (apparently female) was sent from New York to England, and there described and named for a Mrs. Blackburn who collected stuffed birds and was a patron to ornithology.Blackburniae—Gmelin’s latinization, in 1788, of this English name—was its scientific designation until quite recently, when in an obscure German publication, dated 1776, were discovered a description of a specimen from French Guiana (which is well east of the species’ normal winter range), and the namefusca, blackish. Wilson recognized the male as a rare transient near Philadelphia, but when he shot a female (apparently, though he called it a male) in the Great Pine Swamp, Pa., he named itSylvia parus, the Hemlock Warbler. Audubon, too, considered the Blackburnian and Hemlock Warblers distinct.
Blackburnian seems to be a doubly appropriate name, for its upper parts are largely black and its throat burns like a brilliant orange flame amid the dark foliage of the hemlocks and spruces. A glimpse of such a brilliant gem, flashing out from its sombre surroundings, is fairly startling.
Throughout most of the eastern half of the United States the Blackburnian warbler is known only as a migrant, mainly from the Mississippi Valley eastward. Its summer range extends from Manitoba eastward to Nova Scotia, from Minnesota to New England, and southward in the Allegheny Mountains to South Carolina and Georgia, in the Lower Canadian and Upper Transition Zones. For its breeding haunts it prefers the deep evergreen woods where spruces, firs, and hemlocks predominate, or often swampy woods where the black spruces are thickly draped withUsnea, offering concealment for birds and nests.
In Massachusetts, which is about the southern limit of its breeding range in New England, William Brewster (1888) describes its haunts at Winchendon as follows: “On both high and low ground, wherever there were spruces in any numbers, whether by themselves or mixed with other trees, and also to some extent where the growth was entirely of hemlocks, the Blackburnian Warbler was one of the most abundant and characteristic summer birds, in places even outnumbering the Black-throated Green Warbler, although it shunned strictly the extensive tracts of white pines whichD. virensseemed to find quite as congenial as any of the other evergreens.”
Gerald Thayer wrote to Dr. Chapman (1907) that at Monadnock, New Hampshire, it is “a very common summer resident. It is one of the four deep-wood Warblers of this region, the other three being the Black-throated Blue, the Northern Parula and the Canada. While all the other summer Warblers of Monadnock seem better pleased with various sorts of lighter timber, these four are commonest in the small remaining tracts of primeval woodland, and in the heaviest and oldest second growth. But despite this general community of habit, each of the four has marked minor idiosyncrasies. The Blackburnian favors very big trees, particularly hemlocks, and spends most of its life high above the ground.”
Professor Maurice Brooks (1936) says that Blackburnian warblers “are thoroughly at home in the deciduous second-growth timber that in so many places has replaced the coniferous forest. They range down to elevations of 2,500 feet in northern West Virginia. Here they associate with Golden-winged and Chestnut-sided warblers. A favorite perch is on some chestnut tree that has been killed by the blight.” Rev. J. J. Murray tells me that, in Virginia, it is “common above 1,500 feet, wherever there are conifers.” And Thomas D. Burleigh (1941)says of its status on Mount Mitchell in western North Carolina: “Although not known to breed above an altitude of approximately 5,000 feet, this species is fairly plentiful during the late summer in the fir and spruce woods at the top of the mountain, appearing regularly in July and lingering through September.”
Spring.—The Blackburnian warbler is apparently rare in spring in the Atlantic States south of North Carolina; its migration range extends westward to the plains of eastern Texas, eastern Kansas, and eastern Nebraska, but it is rare west of the forested regions of the Mississippi Valley. Professor Cooke (1904) says that the average rate of migration “from the mouth of the Mississippi to its source, where it breeds, appears to be scarcely 25 miles per day.” Forbush (1929) writes:
It is generally regarded as rare in migration in Massachusetts, though probably untold numbers pass over the state every year, but only a few stop here. It is not when the birds are migrating that we see them, but when theystopto rest.* * *I can recall but two instances in my lifetime when myriads of Blackburnian Warblers stopped here, though other similar flights probably have come when I was not there to see. At sunrise one morning in early May, many years ago, when the tiny green leaves were just breaking forth on the tall trees of the woods near Worcester, Blackburnians were everywhere in the tree-tops. They swarmed in the woods for miles. Years later, in Amesbury, on another May morning, the night flight, having met a cold wave from the north with a light frost, had come down to earth and the birds were busily looking for food; many Blackburnians and many other warblers were in the low shrubbery, in the grass, and even on plowed fields in every direction all through the village and about the farms. The sudden cold had stopped them. A few hours later as the day grew warmer they disappeared and were not seen again.
Brewster (1906) says: “We see the beautiful Blackburnian oftenest during the later part of May, in extensive tracts of upland woods, where it spends much of its time in the tops of the larger trees, showing a decided preference for hemlocks and white pines. In Cambridge I have repeatedly observed it in our garden and the immediate neighborhood, usually in tall elms or in blossoming apple trees.”
Nesting.—So far as I can learn, the nest of the Blackburnian warbler is almost always placed in a coniferous tree at heights ranging from 5 feet to over 80 feet above the ground; nests have been reported many times in hemlocks, which seems to be a favorite tree, but also in spruces, firs, tamaracks, pines and even a cedar. Ora W. Knight (1908) says: “I have found them breeding in colonies as a rule, that is to say, in a rather dense, mossy carpeted tract of evergreen woods near the pond at Pittsfield [Maine], covering perhaps a square mile, there were about ten pairs of these birds to be found, and in a tract of similar woods about half this size at Bangor there are often six or eight pair nesting. In other words, in suitable localities they tend to congregate in loosely scattered assemblies, while in less suitablespots, generally none, or at most a single pair will be found.” Of a nest found near Winchendon, Mass., Brewster (1888) writes:
The nest, which was found by watching the female, was built at a height of about thirty feet above the ground, on the horizontal branch of a black spruce, some six feet out from the main stem. Its bottom rested securely near the base of a short, stout twig. Above and on every side masses of dark spruce foliage, rendered still denser by a draping ofUsnea(which covered the entire tree profusely), hid the nest so perfectly that not a vestige of it could be seen from any direction. This nest is composed outwardly of fine twigs, among which some of the surroundingUsneais entangled and interwoven. The lining is of horse hair, fine, dry grasses, and a few of the black rootlets used byD. maculosa. The whole structure is light and airy in appearance, and resembles rather closely the nest of the Chipping Sparrow.
The highest nest of which I can find any record is one reported by Dr. C. Hart Merriam (1885), found by A. J. Dayan in a grove of large white pines (Pinus strobus), in Lewis County, N. Y. It was saddled on a horizontal limb of one of the pines, about 84 feet from the ground and about 10 feet out from the trunk. “The nest is large, substantial, and very compact. It consists almost entirely of a thick and densely woven mat of the soft down of the cattail (Typha latifolia), with seeds attached, and is lined with fine lichens, horse hair, and a piece of white thread. On the outside is an irregular covering of small twigs and rootlets, with here and there a stem of moss or a bit of lichen.”
The lowest nests that I have heard of are recorded in Frederic H. Kennard’s notes from Maine; one was only 51⁄2feet up and the other 9 feet from the ground in small spruces. Mrs. Nice (1932) found a nest near her mother’s home in Pelham, Mass., that was “18 feet from the ground near the top of a cedar among comparatively open, young growth, 40 yards south of the house and 150 yards to the east of the great pines and hemlocks where the male habitually sang.” The only nest of this warbler that I have ever seen was found by watching the female building it, on June 16, 1913, on an island in Lake Winnipegosis, Manitoba; it was only about 10 feet from the ground, near the end of a drooping branch of a large black spruce that stood on the edge of some coniferous woods next to an open swale. The nest, shaded from above, was partly concealed from below by dense foliage and was, apparently, well made of soft fibers, deeply cupped, and lined with some dark material and a little willow cotton. I was not able to visit the island again.
In New York State and in Pennsylvania, the nests of the Blackburnian warbler are almost invariably placed in hemlocks. All of the four nests recorded by T. E. McMullen (MS.) from the Pocono Mountains, Pa., were in hemlocks. And Todd (1940) states that with one exception all the nests found by R. B. Simpson, of Warren,Pa., were in hemlocks, “at elevations varying from twenty to fifty feet. The exceptional nest was in a large chestnut, sixty feet from the ground.”
Dr. Roberts (1936) mentions a Minnesota nest “situated in an arbor vitae tree, directly over the entrance to a cabin,” and one “placed in a small spruce, close to the trunk, about 2 feet from the top of the tree and about 20 feet from the ground.” Another was found in “a jack-pine tree, 20 feet from the ground, 6 feet from the trunk, resting in a tangle of small branches, and concealed by a closely overhanging branch.”
Eggs.—The Blackburnian warbler lays normally 4 or 5 eggs, usually 4; in a series of 14 sets there are only 3 sets of 5. They are ovate to short ovate and slightly glossy. The ground color is snowy white or very pale greenish white, and is handsomely spotted and blotched with “auburn,” “bay,” “argus brown,” “Mars brown,” or “mummy brown,” with undertones of “brownish drab,” or “light vinaceous-drab.” On some eggs the drab marks are the most prevalent, with fewer but more prominent spots or blotches of dark brown shades, such as “Mars brown” and “mummy brown.” Others have spots of “auburn” and “bay” so concentrated that they form a solid band around the large end. In addition a few small scrawls of brownish black are often found. Generally speaking the markings tend to form a wreath, but some eggs are spotted more or less evenly all over the surface. The measurements of 50 eggs average 17.2 by 12.8 millimeters; the eggs showing the four extremes measure18.0by 13.6, 17.0 by13.7,15.6by 12.5, and 17.1 by12.0millimeters (Harris).
Young.—We have no information on incubation and very little on the care of the young. The male has been seen to go onto the nest, and evidently shares occasionally in the duty of incubation. Both parents help in feeding the young, as noted by Mrs. Nice (1932) at the nest she was watching. When Mrs. Nice’s daughter climbed a tree near the nest, the female “assumed a peculiar attitude, her tail outspread and dropped at right angles to her body, her wings flipping rapidly and occasionally held stiffly up or down. The excitement caused the young to jump out on the ground where they could not be found.”
Plumages.—Dr. Dwight (1900) calls the natal down sepia-brown, and in speaking of the males, describes the juvenal plumage as "above, dark sepia-brown obscurely streaked on the back with clove-brown. Wings and tail clove-brown edged with olive-buff, the tertiaries and coverts with white forming two wing bands at tips of greater and median coverts; the outer three rectrices largely white. Below, white, washed with wood brown or buff on breast and sides, spotted, except on chin, abdomen and crissum, with dull sepia. Superciliary stripecream-buff, spot on upper and under eyelid white; lores and auriculars dusky.”
A partial postjuvenal molt begins early in August, involving the contour plumage and the wing coverts but not the rest of the wings or the tail. This produces the first winter plumage, which he describes as “above, deep yellowish olive-gray, flecked on the crown and streaked on the back with black; obscure median crown stripe straw-yellow; rump and upper tail coverts black, edged with olive-gray. Wing coverts clove-brown edged with olive-gray and tipped with white forming two broad wing bands. Below, straw-yellow brightening to orange-tinged lemon on the throat, fading to buffy white on the crissum and narrowly streaked on the sides with black veiled by yellow edgings. Superciliary stripe and post-auricular region lemon-yellow orange-tinged. Auriculars, rictal streak and transocular stripe olive-gray mixed with black. Suborbital spot yellowish white.”
He says that the first nuptial plumage is “acquired by a partial prenuptial moult which involves most of the body plumage (except posteriorly), the wing coverts and sometimes the tertiaries but not the rest of the wings nor the tail. The full orange and black plumage is assumed, young and old becoming practically indistinguishable, the orange throat equally intense in both, the wings and tail usually browner in the young bird and the primary coverts a key to age.”
The adult winter plumage is acquired by a complete postnuptial molt in July, and “differs little from the first winter dress, but the yellow more distinctly orange, the transocular and rictal streaks, the crown and auriculars distinctly black, veiled with orange tips, the streaking below heavier and broader, the wings and tail blacker and the edgings grayer.” The adult nuptial plumage is acquired as in the young bird; this molt evidently begins in February, while the birds are in their winter quarters, and is usually finished before they reach their summer homes.