Life histories of North American wood warblers, Part 1 (of 2)
Part 40
_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 the _Juniperus 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 of _D. 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:
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 similar positions 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 with _thick_ foliage.
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 2-1/2 inches 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 average =17.7= by 13.1 millimeters; the eggs showing the four extremes measure =18.9= by 13.0, 17.8 by =13.7=, and =15.6= by =12.4= millimeters (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 (_Aphis_ sp.) 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 and interested in watching _me_ as 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 of _D. 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 it _tsrr 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 as _tweah, tweak, twee-sy_, with some individuals introducing an extra note or two, and the slower or more deliberate style _twee-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 buzzing _z-z-z-z_ quality 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, scolding _check, check, check_ or _tick, 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 middle of 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: =North= to Kerr (Ingram and Kerrville) and Travis (Austin) Counties; =south= to Bexar (San Antonio) and Medina (Castroville) Counties; and =west= to 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 in searching 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, yellow _Evernia_, 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. (See _Nidologist_, 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 in _The 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 2-1/2 feet 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 in _The 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 layer being 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 of _D. 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 measure =18.0= by 13.4, 17.0 by =13.7=, =15.2= by 12.7, and 16.3 by =11.8= millimeters (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," with two 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.