Chapter V: Introduction (3)

The distribution, migration, and habits of this warbler were but poorly understood by the early writers on American birds, and neither Wilson nor Audubon ever saw its nest; the latter's description of the nest, probably from hearsay, is entirely wrong. Frank L. Burns writes to me: "Bartram neglected to list this species, although he had furnished the type to Edwards 35 years earlier, and from the information furnished by the youthful Bartram it doubtless received its name, which is a misnomer perpetuated by Gmelin in his _Motacilla vermivora."_ Mr. Burns says further on in his notes: "I searched for 10 seasons before I found my first nest, and oddly enough it was through the parent bird carrying a 'worm' to its young; nevertheless I have since thought that a more fitting name for the species would have been hillside or laurel warbler."

Hillside warbler would not be a bad name for this bird, which shows a decided preference for wooded hillsides covered with medium-sized deciduous trees and an undergrowth of saplings and small shrubbery. Often a running stream with numerous swampy places, overgrown with brier tangles and alders, bounds the base of the hill as an additional attraction. It is seldom seen outside of its favorite woods and returns year after year to the same chosen haunts.

W. E. Clyde Todd (1940) says that in western Pennsylvania "wooded slopes are its chosen abodes, the shadier and cooler the better. * * * Deep ravines, down which trickle little streams, and the slopes of which support good stands of deciduous trees, with plenty of shrubbery and bushes for cover, are favorite resorts." In Ritchie County, W. Va., William Brewster (1875) found it "most partial to the retired thickets in the woods along water courses, and seldom or never found in the high open groves."

_Spring._--The northward movement of the worm-eating warbler evidently begins in March, as the earliest arrivals from the Bahamas, the West Indies, and Cuba reach southern Florida during the first week in April. From its main winter resorts in Central America the flight seems to be partially across the Gulf of Mexico. Professor Cooke (1904) says in part: "The time of arrival on the coasts of Louisiana and Texas is about the same as in southern Florida. * * * Houston is the southernmost point in Texas from which it has been recorded to date, and Alta Mira is the northernmost point of record in Mexico. Since the species is apparently not common west of Louisiana or north of Vera Cruz, it is probable that the principal line of migration is from Yucatan and the coast immediately west of Yucatan directly north to the northern coast of the Gulf of Mexico." According to Williams (1945) the species is common on the coast of Texas in spring, and it probably migrates along the coast. Thence the migration proceeds northward through the Mississippi Valley and through the Atlantic Coast States east of the Alleghenies, the warblers reaching the more northern breeding grounds by the middle of May, where nesting activities begin as soon as mates have been selected.

_Nesting._--Evidently Thomas H. Jackson, of West Chester, Pa., was the first to report the discovery of the nest of the worm-eating warbler; he published an account of it in the American Naturalist for December 1869, from which Baird, Brewer, and Ridgway (1874) quote as follows: "On the 6th of June, 1869, I found a nest of this species containing five eggs. It was placed in a hollow on the ground, much like the nests of the Oven-Bird (_Seiurus aurocapillus_), and was well hidden from sight by the dry leaves that lay thickly around. The nest was composed externally of dead leaves, mostly those of the beech, while the interior was prettily lined with the fine, thread-like stalks of the hair-moss (_Polytrichium_). * * * So close did the female sit that I captured her without difficulty by placing my hat over the nest."

This nest was quite characteristic of the species. Mr. Burns writes to me: "The nest, well hidden under a drift of dead forest leaves, never varied in composition in over a hundred examples examined by me, in partly skeletonized leaves and the characteristic reddish-brown lining of the flower stem of the hair moss." Every one of 50 nests found by Mr. Jackson was lined with these flower stems, and out of 34 nests reported by Dr. Samuel S. Dickey (1934) only one failed to contain this material, being lined with "black and gray horsehair." Samuel B. Ladd (1887) says that "sometimes fine grass and horse-hair are used as part of the lining." Dr. Chapman (1907) writes: "Nests taken by J. N. Clark at Saybrook, Connecticut (C. W. C.) are composed of decayed leaves and lined with stems of maple seeds." And there are probably a few other exceptions to the rule.

Most observers agree that the worm-eating warbler prefers to nest on hillsides, either sloping or steep, but a number of nests have been found on the sides of deep, shady ravines, or on steep banks. Mr. Ladd (1887), however, states: "I have observed that these birds are not confined necessarily to hill-sides, as was heretofore supposed, as I have taken three sets on level ground and in rather open places, with little shade. The experience of Mr. Thomas H. Jackson of this place, who has taken ten nests this year, corroborates this fact."

The nests are generally well concealed under a canopy of dead leaves, drifted by the wind and lodged against a maple, beech, dogwood, or ash sapling, or under hydrangea, laurel, or rhododendron bushes, or under some bunch of weeds or other obstruction. They are sometimes concealed under the roots of a tree or in a cavity in a bank where they are protected somewhat by fallen leaves.

_Eggs._--The number of eggs laid by the worm-eating warbler varies from 3 to 6, but the set usually consists of 4 or 5. The eggs are ovate or short ovate, sometimes rather pointed, and only slightly glossy. The white ground color is speckled and spotted with shades of "russet," "vinaceous russet," and "auburn," intermingled with "light brownish drab" and "light vinaceous-drab." The markings, usually more thickly grouped at the large end, vary considerably, some eggs being boldly marked, while others are almost immaculate, or have just a few pale freckles of "light brownish drab" and "fawn." The measurements of 50 eggs average 17.4 by 13.6 millimeters; the eggs showing the four extremes measure =20.8= by =14.5=, and =15.5= by =12.7= millimeters (Harris).

_Incubation._--Frank L. Burns (1905) writes:

Incubation does not always commence immediately after completion of set, particularly if the season be young. It is probable that the second night witnesses the beginning of that period and, as far as my experience goes, I believe it is performed by the female alone. The male feeds her when covering newly hatched young.

The home-coming of a brooding bird, after a brief airing and feeding, is heralded several hundred yards distant by frequent _chips_ and short flights from branch to branch near the ground, in leisurely fashion and circuitous route, until at length, arriving above the nest, she runs down a sapling and is silent. The bird is a close sitter and if approached from the open front will often allow a few minutes' silent inspection, eye to eye, at arm's length, sometimes not vacating until touched, then she runs off in a sinuous trail, not always feigning lameness before the young are out. When disturbed with young in the nest she will flutter off with open wings and tail, and, failing to lead one off, will return with her mate, who is seldom far off at this period, circling about the nest or intruder, and, if the young are well feathered, she will dash at them, forcing them from the nest and to shelter. Once this brave little bird dashed at me and ran up to my knee, scratching with her sharp little claws at every step. On the return the birds always make the vicinity ring with their protests--a quickly repeated _chip_. The period of incubation in one instance was thirteen days.

_Young._--Mr. Burns continues:

Young fear man soon after their eyes are open, and a menacing finger will cause them to scamper out and away, repeated replacing in the nest proving of no avail after they became panic-stricken. At three days of age they made no outcry but opened their mouths for food, which consisted of a species of white moth, or "miller," and soft white grubs, supplied by either of the parent birds. At that period they were naked except a fluff on head and wing quills, just showing feathers at tips. In the presence of an intruder and absence of the parents, they will sit motionless if not threatened, and, but for the blinking, beady eyes, one might mistake them when well fledged, at very close range, for dead leaves. The head stripes became visible under the nestling down on the seventh day, and they left the nest ten days after leaving the shell, in the one case I have kept record of. The parents keep the young together for several days at least, just how long is impossible to say. One brood is all that is reared in a season, I think.

_Plumages._--Dr. Dwight (1900) calls the natal down "brownish mouse-gray," and describes the juvenal plumage as follows: "Whole body plumage and the wing coverts cinnamon, palest on the abdomen. Wings and tail olive-brown edged with olive-green. Two indistinct lateral crown stripes brownish mouse-gray. A transocular streak dusky." Ridgway's (1902) description is somewhat different: "Head, neck, and under parts buff, the pileum with two broad, but strongly contrasted, lateral stripes of wood brown or isabella color; a postocular streak of the same color; back, scapulars, rump, and upper tail-coverts wood brown or isabella color; wing-coverts light buffy olive, the middle and greater broadly but not sharply tipped with cinnamon-buff; remiges and rectrices grayish olive-green, as in adults." Young birds seem to vary considerably in the color of the upper parts.

A partial postjuvenal molt occurring in late June or early July involves all the contour plumage and the wing coverts but not the rest of the wings or the tail. The young bird in its first winter plumage is practically indistinguishable from the adult at that season, except for the juvenal wings, in which the tertials are lightly tipped with rusty brown.

There is apparently no spring molt, but a complete postnuptial molt occurs in July. Spring birds are slightly paler, grayer and less buffy than in the fall. The sexes are practically alike in all plumages.

_Food._--As I have said, the name worm-eating warbler seems to be somewhat of a misnomer for this bird. Edward H. Forbush (1929) writes: "I find no records of any consumption of earthworms by this species, which although a typical ground warbler spends some of its time hunting among the branches of trees, where it finds span-worms. It also hunts on the ground in damp places frequented by army-worms. Nevertheless these are not worms but caterpillars. Probably, however, in its perambulations and peregrinations upon the surface of the earth the bird now and then does pick up a small earthworm, for earthworms form a staple food for many birds when the ground is moist."

Arthur H. Howell (1924) says: "Little is known of the food of this species, but it seems doubtful whether it lives up to its name of worm-eater.' Two stomachs of this bird from Alabama contained remains of weevils, beetles, bugs, caterpillars, and Hymenoptera." Howell (1932) further reports: "The stomachs of three individuals taken in Florida in April contained small grasshoppers, caterpillars, sawfly larvae, beetles, and spiders. One dragon-fly, one bumblebee, and one 'walking stick' were also included in the contents." Professor Aughey (1878) included the worm-eating warbler among the birds seen catching locusts in Nebraska.

_Behavior._--Brewster (1875) gives the best account of the activities of the worm-eating warbler as follows:

They keep much on the ground, where they _walk_ about rather slowly, searching for their food among the dried leaves. In general appearance they are quite unique, and I rarely failed to identify one with an instant's glance, so very peculiar are all their attitudes and motions. The tail is habitually carried at an elevation considerably above the line of the back, which gives them a smart, jaunty air, and if the dorsal aspect be exposed, in a clear light, the peculiar marking of the crown is quite conspicuous. Seen as they usually are, however, dimly flitting ahead through the gloom and shadow of the thickets, the impression received is that of a dark little bird which vanishes unaccountably before your very eyes, leaving you quite uncertain where to look for it next; indeed, I hardly know a more difficult bird to procure, for the slightest noise sends it darting off through the woods at once. Occasionally you will come upon one winding around the trunk of some small tree exactly in the manner of _Mniotilta varia_, moving out along the branches with nimble motion, peering alternately under the bark on either side, and anon returning to the main stem, perhaps in the next instant to hop back to the ground again. On such occasions they rarely ascend to the height of more than eight or ten feet. The males are very quarrelsome, chasing one another through the woods with loud, sharp chirpings, careering with almost inconceivable velocity up among the tops of the highest oaks, or darting among the thickets with interminable doublings until the pursuer, growing tired of the chase, alights on some low twig or old mossy log, and in token of his victory, utters a warble so feeble that you must be very near to catch it at all, a sound like that produced by striking two pebbles very quickly and gently together, or the song of _Spizella socialis_ heard at a distance, and altogether a very indifferent performance.

_Voice._--Aretas A. Saunders has contributed the following study of the song of this warbler:

The song of the worm-eating warbler is a simple trill, varying from 1-2/5 to 2-1/5 seconds in length. It is usually all on the same pitch, but a few songs rise or fall a half tone, and one record I have rises a full tone and then drops a half tone at the end. The quality is not musical, but rather closely resembles some forms of the chipping sparrow's song. The pitch varies from G sharp´´´ to F sharp´´´´, one tone less than an octave.

The majority of songs are a continuous trill, that is, the notes are too fast to be separated and counted by ear. I have three examples that are broken into short, very rapid notes. Two of these were of 18 notes and one was of 28. Most of the songs vary in loudness, becoming loudest in the middle, or beginning loud and fading away toward the end. One record becomes louder toward the end and ends abruptly.

Francis H. Allen describes in his notes a song "remarkably like that of the chipping sparrow, but more rapid than is usual with that species, I think, and perhaps shorter, though not so short as the chippy's early-morning song. The bill quivers with the song, but does not close between the _chips_. The bird sang constantly as it flitted about, usually 10 or 20 feet from the ground, seeming to prefer dead branches and twigs."

Almost everyone emphasizes the resemblance of the song to that of the chipping sparrow. Burns (1905) says: "I can distinguish no difference between the notes of this species and the Chipping Sparrow; the first may be a trifle weaker perhaps." But, in some notes recently sent to me, he writes: "The song has often been described as easily mistaken for that of either the chipping sparrow or slate-colored junco, but by no means by an expert. The notes of the worm-eater have a buzzing or bubbling quality not easily described, but are quite distinct from the flat notes of the species named above." And Eugene P. Bicknell (1884) writes: "The songs of no other three birds known to me are more alike than those of the Worm-eating Warbler, the Chipping Sparrow, and the Slate-colored Snowbird." He is in agreement with Saunders and Burns that this bird sings from the time of its arrival until the last of June or early July, but he also says: "On July 10, 1881, several of these birds were silently inhabiting a small tract of woodland, their first season of song having passed; here, on August 14, and again on the 21st, they were found in fine plumage and in full song." Evidently there is a cessation of singing during the molting period.

Burns (1905) says of the song: "The series of notes may be uttered while perched, or creeping about the lower branches of the trees, sapling tops, bushes or fallen brush, or while on the ground. With slightly drooping tail and wings, puffing out of body plumage, throwing its head back until the beak is perpendicular, it trills with swelling throat an unvarying _Che-e-e-e-e-e-e_, which does not sound half so monotonous in the woods as does the Chippy's lay in the open."

Dr. Chapman (1907) adds: "Mr. W. DeW. Miller of Plainfield, New Jersey, tells me that he has on two occasions heard a flight song from this species. It is described by him as much more varied and musical than the ordinary song, though lacking in strength. It was given as the bird flew through the woods at an even level, not rising above the tree-tops, as does the Oven-bird and other flight singers."

_Field marks._--When seen walking around on the ground the worm-eating warbler might be mistaken for an ovenbird, but the conspicuous black stripes on the head of the former are quite distinctive, very different from the head markings of the latter. Moreover, the ovenbird is distinctly spotted on the breast, whereas the warbler has a plain, unmarked breast and no conspicuous wing bars. Except for the bold stripes on the head it is just a plain olive and buffy warbler in all plumages.

_Enemies._--Says Burns (1905): "This Warbler's enemies are wood-mice, red squirrels and hunting dogs; the latter will sometimes push up and overturn the nest; an occasional weasel or blacksnake may destroy a few young. The percentage of loss while in the nest cannot be high."

Friedmann (1929) regards the worm-eating warbler as a "rather uncommonly imposed upon species" by the eastern cowbird. "Twenty-one definite records, and as many more indefinite ones have come to my notice."

_Winter._--Dr. Alexander F. Skutch contributes the following: "Widely distributed as a winter resident in Central America, the worm-eating warbler appears to be everywhere very rare. It occurs from Guatemala to Panamá on both coasts, and upward in the mountains to at least 5,000 feet. On February 26, 1935, I found one in the forest on Barro Colorado Island, Canal Zone, which appears to represent a slight southward extension of the known range. I have recorded this rare visitant from every part of Central America below 6,000 feet in which I have made an extended sojourn during the months of the northern winter, yet only one or two in each locality, except on the Finca Mocá on the Pacific slope of Guatemala at 3,000 feet above sea-level, where in one day--January 21, 1935--I saw three. The worm-eating warbler is found in the Tropics beneath dense thickets or in the undergrowth of the forest, usually near the ground; but at times one will rise to the lower branches of the trees to investigate curled dead leaves caught up among them. It is solitary rather than social in its habits.

"The records of the occurrence of this warbler in Central America are too few to indicate clearly the dates of its arrival and departure. I found one at Tela, Honduras, on August 19, 1930; but the next early record is for October 14, at the same locality. Griscom quotes a record by Dearborn for the occurrence of this warbler at Patulul, Guatemala, on April 2; but except for this, the latest record I have seen is from El General, Costa Rica, March 11, 1939."

DISTRIBUTION

_Range._--Eastern United States to Panamá.

_Breeding range._--The worm-eating warbler breeds =north= to northeastern Kansas (Lawrence); possibly central southern Nebraska (Red Cloud); probably south-central Iowa (Des Moines); probably southern Wisconsin (Wyalusing, Madison, and Milwaukee); northeastern Illinois (Hinsdale); southern Indiana (Terre Haute, Bloomington, and Indianapolis); central Ohio (Columbus, East Liverpool, and possibly Cleveland); southern New York (Penn Yan and Albany), and southern Connecticut (New Haven and Saybrook). It has been found in summer north to London, Ontario; Northampton, Ipswich, and North Eastham, Massachusetts. =East= to Connecticut (Saybrook); Long Island (Newtown); northern New Jersey (Elizabeth and Morristown); eastern Pennsylvania (Norristown and Philadelphia); northern Delaware (Wilmington); central Maryland (Baltimore; rarely east of Chesapeake Bay); eastern Virginia (Cobham and Dismal Swamp); central North Carolina (Chapel Hill and Statesville); northwestern South Carolina (Caesars Head, Mount Pinnacle, and Sassafras Mountain); and northern Georgia (Brasstown Bald and Atlanta). =South= to northern Georgia (Atlanta); central Tennessee (Nashville and Wildersville); northern Arkansas (Newport and Winslow); and, occasionally, extreme northern Texas (Bowie County and Gainesville). =West= to northern Texas (Gainesville); northeastern Oklahoma (Jay); and eastern Kansas (Lawrence). It has been recorded in summer, but with no evidence of breeding, at Red Cloud, Nebr., and at London and Vineland Station, Ontario.

_Winter range._--In winter the worm-eating warbler is found =north= to southern Tamaulipas (Altamira); northern Florida, casually (Blue Springs and Amelia Island), and the Bahamas (Abaco, Nassau, and Great Inago). =East= to the Bahamas (Great Inago); Jamaica and central Panamá (Río Chepo). =South= to Panamá (Río Chepo, Barro Colorado, and Chiriquí). =West= to western Panamá (Chiriquí); Costa Rica (Escasú and Volcán Tonorio); El Salvador (Mount Cacaguatique); Guatemala (Dueñas, Patulul, and Naranjo); southern Chiapas (Huehuetán); western Veracruz (Jalapa); Hidalgo (Pachuca); and southern Tamaulipas (Altamira).

_Migration._--Late dates of spring departure are: Panamá--Darién March 16. Costa Rica--El General, March 19. El Salvador--Barra de Santiago, April 8. Guatemala--Patulul, April 2. Yucatán--Mérida, April 9. Cuba--Habana, May 1. Bahamas--Abaco, April 29. Florida--Seven Oaks, May 14. Georgia--Cumberland, May 7. Alabama--Barachias, May 1. Mississippi--Biloxi, April 27. Louisiana--Avery Island, April 23.

Early dates of spring arrival are: Florida--Pensacola, March 26. Georgia--Savannah, April 4. South Carolina--Mount Pleasant, April 7. North Carolina--Bat Cave, April 16. Virginia--Richmond, April 19. West Virginia--Morgantown, April 4. District of Columbia--Washington, April 21. Pennsylvania--Beaver, April 29. New York--Jones Beach, April 20. Louisiana--Grand Isle, April 3. Mississippi--Bay St. Louis, April 5. Tennessee--Chattanooga, April 15. Kentucky--Bowling Green, April 3. Indiana--Brookville, April 17. Ohio--Columbus, April 18. Texas--Brownsville, March 29. Missouri--St. Louis, April 15. Iowa--Keokuk, April 21.

Late dates of fall departure are: Missouri--St. Louis, September 20. Ohio--Austinburg, September 23. Kentucky--Middlesboro, September 27. Tennessee--Athens, October 5. Mississippi--Biloxi, October 11. Louisiana--Monroe, September 30. New York--Balston, September 23. Pennsylvania--Atglen, October 10. District of Columbia--Washington, September 13. West Virginia--Bluefield, September 19. Virginia--Salem, October 24. North Carolina--Andrews, October 11; Raleigh, November 3. South Carolina--Charleston, October 11. Georgia--Atlanta, October 10. Florida--Fernandina, October 3.

_Casual records._--A specimen was collected in Bermuda on October 4, 1899. An individual was present at Wood Pond near Jackson, Somerset County, Maine, September 1 to 12, 1935; and one was reported seen at Mayagüez, Puerto Rico, on October 15, 1943, following a small hurricane.

_Egg dates._--Connecticut: 7 records, May 27 to June 29.

New Jersey: 4 records, May 21 to 30.

Pennsylvania: 75 records, May 15 to June 30: 45 records, May 24 to June 5, indicating the height of the season (Harris).

VERMIVORA CHRYSOPTERA (Linnaeus)

GOLDEN-WINGED WARBLER

CONTRIBUTED BY WINSOR MARRETT TYLER

PLATES 10, 11

HABITS

The golden-winged warbler is one of the daintiest among this group of gay-colored little birds. Its plumage is immaculate white below and delicate pearl-gray on the upper parts, the crown and wings sparkle with golden yellow, and on the throat and cheeks is a broad splash of jet black.

It is only within comparatively recent years that we have become well acquainted with the goldenwing: the older ornithologists, Wilson, Audubon, and Nuttall, knew it only as a rather uncommon migrant, drifting through from the south, and they had no idea where it bred. At a much later date J. A. Allen (1870) says of it: "This beautiful warbler has been taken, so far as I can learn, but few times in the western part of the State; it seems to be more common in the eastern, where it breeds." He cites the first record of the finding of a nest in the State in 1869. There is, however, an earlier record of its nesting. Dr. Brewer (1874) states: "Dr. Samuel Cabot was the first naturalist to meet with the nest and eggs of this bird. This was in May, 1837, in Greenbrier County, Va."

William Brewster (1906), speaking of the bird in 1874, when he first found it in eastern Massachusetts, says: "If the species inhabited any part of the Cambridge Region before the year just mentioned, it was overlooked by several keen and diligent collectors, among whom may be mentioned Mr. H. W. Henshaw and Mr. Ruthven Deane." Since that time the bird has increased in numbers here until at present it is common in suitable localities.

_Spring._--The goldenwing appears in eastern Massachusetts about the middle of May, or sometimes a little earlier, at the time when many of the resident warblers are arriving on their breeding-grounds. At this season the bright green leaves are beginning to open in the thickets and trees on the borders of woodlands where the goldenwing finds its food; and under the trees in the wooded swamps where the bird will build its nest, fresh new growth--skunkcabbage, ferns, and a host of spring plants--is pushing through the dead leaves, spreading a green carpet on the forest floor. But even thus early in the year, when the trees are nearly bare, it is not easy to see as it feeds high up in the trees, far out near the tips of the branches. Indeed, but for its queer little song, we should rarely suspect that it had come back to its summer home.

_Nesting._--The golden-winged warbler builds its nest on the ground, generally raised somewhat by a substratum of dead leaves. The nest is supported by stalks of herbs--often goldenrod or meadow rue--or by fern fronds, or it may be hidden deep in a clump of grass, or it may lean against the base of a small shrub or tree with grass all about it. The leaves above the nest develop as the season advances and soon completely conceal it, and the plants, by their growth, may raise the nest a little above the ground. The cup of the nest is made chiefly of long strands of dry grass and narrow strips of grapevine bark, with a few hairs in the lining. This fine, flexible material is pressed down on the inside by the weight of the incubating bird and the nestlings, becoming smooth and firm like a mat, whereas on the outside wall the long grass blades and fibrous vegetable shreds are left free and, protruding loosely in all directions for some distance from the cup, produce a disorderly, unkempt appearance, like a little loose handful of fine hay.

Edward H. Forbush (1929) quotes an account of the goldenwing by Horace O. Green who has had an extensive experience with the species and who gives the following interesting details of the construction of the nest:

The nest of the Golden-wing usually has a bottom layer of coarse dead leaves on which is placed a ring of large dry leaves, arranged with the points of the leaves downward, so that the leaf stems stick up noticeably around the edges of the nest proper, which is built within and upon this circular mass of leaves, and is made of rather wide strips of coarse grass or rushes, and usually has considerable grape vine bark interwoven in it. The nest lining is coarse and rough, sometimes the eggs being laid on the rough grape vine bark, and in some nests other coarse fibers are used. A very characteristic feature of the nest lining is fine shreds of light reddish-brown vegetable fiber, which at first glance might easily be mistaken for dry needles from the pitch pine--but careful examination shows it to be the inner layers of the bark from the grape vines. The nest is very bulky for the size of the bird and Is rather loosely put together by crossing the materials diagonally, so that it slightly resembles a rather coarse basket-work. I never saw a nest of this species which had a soft lining, such as many other warblers use--the eggs are apparently always deposited on rough material.

The general color of the nest is very dark, especially just after a rain, when the materials of which it is composed look almost black--this being one thing which helps to distinguish these nests from those of the Maryland Yellow-throat, which generally builds a much lighter colored nest, lined with fine grass, and sometimes with horse hair. Another small point of difference which is noticeable on close examination is that the lining in the Yellow-throat's nest is usually of a much finer and lighter colored material, and appears to be woven in horizontally, or at least to show some traces of such a design, especially around the upper edge--while the Golden-wing closely adheres to the diagonal criss-cross pattern with the loose ends of the nesting materials sticking up at an angle above the rim of the nest cavity.

Mr. Green describes the surroundings of the nest thus:

For their summer home these birds prefer the border of deciduous woods, where tall trees give plenty of shade, to an adjacent clearing with a growth of briers, bushes and grass, and the nest is usually placed just outside the line of the forest proper, but within the shade of the trees. A meadow wholly surrounded by woods is frequently selected. The ideal place to search for a nest of the species is in one of those woodland meadows, which has a clear brook flowing through it, with briers, tussocks of grass and a fresh growth of goldenrod scattered around in profusion, with birch trees and wild grape vines growing near the edges where the meadow meets higher ground--and all this bordered by tall oak, chestnut and maple trees which furnish an abundance of shade to the vegetation of the meadow itself.

J. Warren Jacobs (1904) describes the nest much as above and adds: "The opening is not straight down, but slightly tilted, the jaggy leaf-stems and bark sometimes reaching two or three inches above the rim of the nest proper. As incubation advances, the rough rim on the lower edge of the nest becomes broken down, and by the time the young birds are ready to leave, this part of their home is worn smooth by the attendant parents."

He gives the measurements of 17 nests as follows: "Outside 3.6 to 5.0 inches in diameter, and 3.0 to 5.0 inches in depth; and on the inside, from 1.7 to 2.5 inches in diameter by 1.3 to 2.5 inches deep." These measurements agree very closely with the records of several other observers. Jacobs continues: "Seemingly before the birds have had time to complete their nest, the female begins the deposition of the eggs. Generally, where I had opportunity to watch the nests daily, or at intervals between the beginning and completion of the set, the eggs were laid on consecutive days, but in two or three instances it was noticed that the laying missed a day."

_Eggs._--The set for the golden-winged warbler may consist of anywhere from 4 to 7 eggs; 5 is perhaps the commonest number, but 4 is a common number, and the larger numbers are increasingly rare. The eggs are ovate or short ovate, and have only a slight luster. They are white or creamy white, with a wide variety of markings in "auburn," "argus brown," "Mars brown," "hazel," "Hay's brown," "liver brown," and "burnt umber," with underlying speckles or spots of "light brownish drab" and "light vinaceous drab." There is, also, much variation in the amount of markings, some being very sparingly speckled and others are quite heavily marked, with some of the spots assuming the proportions of blotches. Occasionally small hairline scrawls, or scattered spots, of brown so dark as to appear almost black, are found. The markings are usually denser toward the large end. The measurements of 50 eggs average 16.7 by 13.0 millimeters; the eggs showing the four extremes measure =18.6= by 13.0, 16.8 by =13.7=, =15.5= by 12.5, and 15.9 by =12.3= millimeters (Harris).

_Young._--Jacobs (1904) states that the incubation period is 10 days and that the young birds are able to leave the nest 10 days after hatching. In a nest which Maunsell S. Crosby (1912) watched closely, the eggs hatched on June 1 and the young flew on June 10.

The fledglings are delicate little birds, brownish olive on the back, washed with yellow below, and have two widely separated yellow wing bars. They have astonishingly long legs and soon become very active, fluttering about in the shrubbery and clinging to the branches. Walter Faxon (1911) in speaking of them gives this lively picture which could well be applied to them soon after leaving the nest: "In appearance and habit they were grotesque little fellows, clinging with their disproportionately long legs to the low herbage, like peeping Hylas in the springtime clinging to the grasses and weeds above the surface of the water. The little thread-like natal plumes still waving from the tips of their crown feathers enhanced the oddity of their appearance." Mr. Faxon, to be exact, is speaking here of some young birds of mixed parentage, but his words apply equally well to the behavior and appearance of the young of _chrysoptera_ which he and I watched year after year together. Both parents are very attentive to their young brood, bringing to them food which they find both on low plant growth and high in the overshadowing branches.

The fledglings call to their parents with a very characteristic note, a little quavering, high, fine chirp which I find written in my journal _crrr_ and _tzzz_. It suggests somewhat a note of young chipping sparrows, but is less sharp and crisp. In form it also resembles the call of the young cowbird, but again it is gentler and weaker in tone. Mr. Faxon (1911) refers to it as the "cricket note." The young birds acquire their first winter plumage about a month after they leave the nest, and hence to the eye are indistinguishable from their parents, but as they still continue to use the call of their babyhood, they may be recognized as immature birds even when they are feeding high up in the trees.

_Plumages._--[AUTHOR'S NOTE: I can find no description of the natal down. Dr. Dwight (1900) describes the juvenal plumage, in which the sexes are practically alike, as "above, grayish or brownish olive-green. Wings and tail slate-black edged chiefly with bluish plumbeous gray, the coverts and tertiaries with olive-green. Below, pale olive-yellow, the throat dusky. Transocular streak dusky. * * *

"First winter plumage acquired by a partial postjuvenal moult, beginning early in July, which involves the body plumage and wing coverts, but not the rest of the wings nor the tail, young and old becoming practically indistinguishable." He describes the young male in this plumage as--

above, plumbeous gray veiled with olive-green edgings; the crown bright lemon-yellow veiled posteriorly only. Below, grayish white, with yellow edgings here and there, the chin, jugulum, lores and auriculars jet-black veiled slightly with pale buff. Broad submalar stripes joining at angle of the chin, and superciliary lines white. Outer half of median and greater coverts bright lemon yellow forming an almost continuous wing patch, lesser coverts plumbeous gray, edged with olive-green.

First nuptial plumage acquired by wear, through which the buff edgings of the black areas, the olive edgings of the back and the yellow edgings below are almost completely lost, the plumage becoming clear gray, white, yellow and black.

Of the female, he says: "In first winter and other plumages olive-gray, dusky on the lores and auriculars, replaces the black areas of the male, and olive-yellow marks the crown. Above, the plumage is greenish; the submalar stripes are grayish." Subsequent plumages are acquired by a complete postnuptial molt in late June and July and by wear in early spring.]

_Food._--Little exact information has been gathered regarding the food of the goldenwing. The insects it feeds on are mainly so small that it is generally impossible to identify them. Jacobs (1904) states: "Once I saw a female carry a small brownish butterfly to her young; and several times I have discovered the birds taking small smooth green worms--such as strip the leaves of their green coat, leaving the ribbed skeleton--to their nestlings. The legs of a spider protruded from a bird's bill as she approached her nest."

The little pale green larva which Jacobs mentions impresses us as the chief article of food, as we watch the birds. It is 1/2 to 3/4 inch long and appears to have a smooth, hairless skin. These larvae are obtained, I believe, chiefly in the large trees.

In the following note A. L. Nelson (1933) furnishes an interesting detail of the bird's diet:

The following observation on the food habits of a Golden-winged Warbler (_Vermivora chrysoptera_), made in the vicinity of Port Tobacco (Charles Co.), Maryland on May 6, 1933, seems worthy of mention, inasmuch as little specific information on the dietary habits of this species has been recorded. About 1:30 we observed a single individual of this species actively feeding in a low shrubbery growth of pawpaw (_Asimina triloba_), which was in full bloom at this date. Closer observation revealed that the bird was probing about inside the flowers, and apparently was getting some kind of larvae. Examination of the flowers revealed that they were infested with a small, brown-headed lepidopterous larva. Dissection of a large number of flowers indicated that the infestation was high, the majority of flowers having one larva, although in many cases two were present. Several infested flowers were collected for the purpose of rearing the insects to the adult stage under laboratory conditions. The cycle was completed without difficulty, the adults emerging within twelve days. These were examined by Dr. Carl Heinrich of the U. S. National Museum and found to be _Talponia plummeriana_ Busck, a small brightly colored Tortricid, the only known food plant of which is the pawpaw.

_Behavior._--A favorite locality for the golden-winged warbler to spend the summer in eastern Massachusetts may be the border of a wooded swamp where tall elm and maple trees shade a dense undergrowth of ferns and other moisture-loving plants, a swamp which runs out toward drier ground where abounds a growth of gray birches or a tangle of raspberry canes, wild grapevines, and goldenrod. Such a spot furnishes countless situations for hiding the nest in the thick vegetation growing in the half-wet half-dry ground, and also a source of food near at hand in the high branches of the trees. Much the same conditions exist along the course of a brook winding through second growth, or near orchards or old neglected weedy pastures.

Sometimes, as William Brewster (1906) points out, the bird may frequent "dry hillsides covered with a young sprout growth of oak, hickory or maple."

In a more southern latitude the habitat may be quite different. Maurice Brooks (1940), speaking of the bird in the central Allegheny Mountain region, says: "Shunning the swamps which it frequents in other portions of its range, it is highly characteristic of the 'chestnut sprout' association, where the males choose dead chestnuts for perches from which to sing. It is also fairly common in the pitch and scrub pine regions on the hills just back of the Ohio river, but becomes less common toward the eastern portion of the territory with which this paper deals. It ascends to at least 4,000 feet in Giles Co., Va."

We can watch the little golden-winged warblers best, and often at very short range, when they are feeding their fledglings recently from the nest. The little birds sit quietly in the shrubbery near the ground, waiting for their parents. We can find them easily, for they frequently utter their characteristic "cricket note," and we can approach them closely, for they scarcely heed us. The parents, too, when they are feeding the young birds, pay little attention to us and come fearlessly to them even when we stand near. At such times they work in a seeming panic of hurry, flying about in the low growth searching for food, or visiting the smallest branches high up in the trees, where they cling to the terminal twigs, hanging like chickadees as they probe among the curled up leaves (insect nests) for food hidden there, then back to the waiting young, seemingly in continuous motion and without the slightest pause in their nervous activity. At this season when the parents are busy with the young birds, about the third week in June in eastern Massachusetts, they are so occupied in searching for food that the male rarely sings.

In two particulars--their tameness, or indifference to our presence, and the almost complete cessation of singing thus early in the season--the goldenwing differs from the other common birds which breed in much the same regions, the chestnut-sided warbler, redstart, northern yellow-throat, ovenbird, and veery.

Jacobs (1904) speaks of the anxiety of the parent birds if the nest is disturbed when the nestlings are nearly ready to fly. He says: "If the hand is placed near the nest at this period of their growth, they will scramble out and flutter away, all giving vent to their chipping note, which brings down upon the intruder the wrath of both old birds, who fly close to his face, snapping their beaks and chipping loudly; then down upon the ground they fall and feign the broken wing act as long as one of the young continues to chirp."

_Voice._--The song of the golden-winged warbler is an inconspicuous little buzzing sound which one might pass by unnoticed, or hearing it for the first time, might ascribe it to a mechanical sound made by some insect, not suspecting it to be the song of a bird. Only after we have become thoroughly familiar with the song do we grasp its definite character, so that we can pick it out even when we hear it in the distance among a medley of other voices. In this particular it resembles the songs of Henslow's and the grasshopper sparrows, which are scarcely audible, and pass unregarded until well known.

The male goldenwing sings generally from a high perch, often from a branch bare of leaves; hence, once we find him, we can see him plainly. When he sings he throws his head back so far that his bill points almost to the zenith, and sings with it widely open, as if he were pouring out a great volume of sound. The bird sings freely from his arrival in spring until mid-June, about a month, often devoting himself to long periods of singing from the same perch. Later in the season, after the young have hatched, he sings only fitfully.

The song most often heard is composed of four notes, the first prolonged, and followed, after an almost imperceptible pause, by three shorter notes on a lower pitch. All four notes are delivered in a leisurely manner, drawling in tempo, and might be written _zeee, zer-zer-zer_. The first note takes up about half the time of the song. The quality of the voice is buzzing, and when heard near at hand, slightly rasping, with a lisping suggestion throughout. The song carries well; curiously it seems little louder when heard at close range, but from a distance it sounds smoother and, losing much of the buzzing quality, suggests a long drawn out _thth_, _th-th-th_, like a whispering wind. Occasionally there may be four short notes, and sometimes only two following the long initial note.

Like some of the other warblers, notably the black-and-white, chestnut-sided, and black-throated green, the goldenwing sings two distinct songs. In the second form the buzzing tone is nearly or wholly absent. It begins with about half a dozen short notes given in a quick series on the same pitch, and ends with one long note on a higher key, _th-th-th-th-th-th-theee_.

I have heard two males singing antiphonally, the responses repeated with perfect regularity for several minutes.

Of the minor notes the commonest is a short, slightly roughened _dz_. When much excited both adults use a chattering _tchu-tchu-tchu_, suggesting in manner of delivery the song of the short-billed marsh wren, although it is higher pitched and not so loud.

Francis H. Allen (MS.) mentions two other songs, only slightly different from the above. One goes something like "_tick tick chick chick chick chick shree_. The _shree_ is a beady note resembling one of the cedar waxwing's familiar notes." Another song he writes as "_see-see-see-see-see-see-see-see-see-dz'-dsee_."

_Field marks._--The golden-winged warbler is easy to recognize; it is the only warbler that combines a blue-gray back and yellow in the wing. In the two other common warblers with a black throat, the black-throated blue and the black-throated green, the black runs down the sides a little way so that the white of the breast comes up in a peak in the middle of the breast, whereas in the goldenwing the line of division between the black and white runs straight across. From directly below, the goldenwing appears wholly black and white, and from this angle is marked like a chickadee, but a glance at its long, needle-sharp bill proclaims it a warbler of the genus _Vermivora_.

_Enemies._--Prowling mammals, the enemies of ground-nesting birds, and predatory hawks are a danger to the bird. In its relation to the cowbird, Friedmann (1929) reports the bird as "a very uncommon victim." He says: "I have only six definite records, but the species is listed as a molothrine victim by Bendire and by Short. As many as four eggs of the Cowbird have been found in a single nest of this Warbler."

_Fall_ and _winter_.--We lose sight of the goldenwing early in the season. Silent amid the dense foliage of July and August, the bird is rarely seen. During the years between 1907 and 1920, when I kept a daily record of birds seen, I met it only four times in August and only twice in September, the latest September 12.

Dr. Alexander F. Skutch sends to A. C. Bent the following account of the bird in its winter quarters: "I am familiar with the golden-winged warbler in its winter home only in Costa Rica. In this country it winters on the Caribbean slope from the lowlands up to about 6,000 feet above sea-level, and on the Pacific slope at least in the region between 2,000 and 4,000 feet. While it appears to be nowhere abundant, I found it most numerous at Vara Blanca, on the northern slope of the Cordillera Central at an elevation of about 5,500 feet. Here on one day--November 2, 1937--I saw three individuals, the greatest number I have ever recorded. This is a region of dense vegetation, subject to much cloudiness and long-continued, often violent rainstorms--one of the wettest districts of all Central America. Most of the published records are from this generally wet side of the country. Yet the bird winters sparingly in the Basin of El General on the Pacific slope, which during the first 3 months of the year may be nearly rainless. While in the Tropics, it appears never to associate with others of its own kind, but at times may roam about with mixed flocks of other small birds. It may forage among low, fairly dense, second-growth thickets, or among the tangled vegetation at the forest's edge, or at times in the forest itself, or in groves of tall trees, high above the ground. It investigates the curled dead leaves caught up among the branches, and devours such small creatures as it finds lurking in their folds. I have not heard it sing while in its winter home.

"In Costa Rica, it appears to arrive late and to depart early, not having been recorded before September 15, nor later than April 9. Early dates of fall arrival are: Costa Rica--San José (Cherrie), September 15 and October 2; La Hondura (Carriker), September 21; Basin of El General, October 18, 1936; Vara Blanca, October 5, 1937.

"Late dates of spring departure are: Costa Rica--Basin of El General, April 8, 1936, April 7, 1937, March 30, 1939, and April 9, 1943; Vara Blanca, April 9, 1938; Guápiles (Carriker), March 30."

DISTRIBUTION

_Range._--Eastern United States to northwestern South America.

_Breeding range._--The golden-winged warbler breeds =north= to central Minnesota (Detroit Lakes, Onamia, and Cambridge); central Wisconsin (St. Croix Falls, New London, and Shiocton); northern peninsula or Michigan (McMillan and Mackinac Island); southern Michigan (Kalamazoo, Locke, and Detroit); southern Ontario (London and Port Rowan, has occurred north to Collingwood and Bowmanville); central New York (Medina, Rochester, and Waterford); central Vermont (Rutland), and northern Massachusetts (Winchendon, Newton, and Lynn). It has been found in summer and may possibly breed in southern New Hampshire (Concord and Durham); and southwestern Maine (Emery Mills and Sandford). =East= to eastern Massachusetts (Lynn, Boston, and Rehoboth); southern Connecticut (New Haven and Bridgeport); northern New Jersey (Morristown); central Pennsylvania (near State College); and south through the mountains to western North Carolina (Weaverville, Waynesville, and Highlands); northwestern South Carolina (Caesars Head and Highlow Gap); and northern Georgia (Young Harris, Margret, and Oglethorpe Mountain). =South= to northern Georgia (Oglethorpe Mountain and Rising Faun); central Tennessee (Maryland); northern Ohio (Steuben, Port Clinton, and Wauseon); northern Indiana (Waterloo); and northern Illinois (Riverside). =West= to northern Illinois (Riverside); central and western Wisconsin (Baraboo Bluffs and Durand); and central Minnesota (Minneapolis, Elk River, and Detroit Lakes). It has been noted in summer, or in migration, west to St. Louis, Mo.; Lake Quivira and Lawrence, Kans.; and Omaha, Nebr.

_Winter range._--In winter the golden-winged warbler is found =north= to central Guatemala (Cobán); and northern Honduras (Lancetilla); casually or in migration to the Yucatán Peninsula (Campeche and Mérida). =East= to Honduras (Lancetilla); eastern Nicaragua (Escondido River); Costa Rica (Guápiles and Guayabo); central Panamá (Lion Hill, Canal Zone); and central Colombia (Santa Marta region, Bogotá, and Villavicencio); rare or accidental in western Venezuela (Mérida). =South= to central Colombia (Villavicencio and El Eden). =West= to northwestern Colombia (El Eden, Medellín, and Antioquia); western Panamá (Chiriquí); Costa Rica (El General and Nicoya); and central Guatemala (Cobán).

_Migration._--Late dates of spring departure are: Colombia--Fusagasugá, March 24. Panamá--Volcán de Chiriquí, April 16. Costa Rica--Vara Blanca, April 9. Florida--Pensacola, April 22. Alabama--Hollins, May 7. Georgia--Athens, May 13. South Carolina--Clemson College, May 3. North Carolina--Raleigh, May 7. District of Columbia--Washington, May 20. Mississippi--Gulfport, April 18. Missouri--St. Louis, May 25.

Early dates of spring arrival are: Florida--Pensacola, April 5. Alabama--Barachias, April 22. Georgia--Milledgeville, April 12. South Carolina--Clemson College, April 21. North Carolina--Asheville, April 23. Virginia--Lynchburg, April 19. West Virginia--Bluefield, April 19. District of Columbia--Washington, April 24. Pennsylvania--Beaver, April 24. New York--Rochester, April 29. Massachusetts--Belmont, April 28. Louisiana--Grand Isle, April 6. Mississippi--Gulfport, April 10. Tennessee--Memphis, April 12. Illinois--Olney, April 17. Indiana--Sedan, April 27. Michigan--Plymouth, April 30. Ohio--Youngstown, April 27. Ontario--London, April 30. Missouri--St. Louis, April 18. Iowa--Keokuk, April 27. Wisconsin--Sheboygan, April 30. Minnesota--Minneapolis, April 30. The golden-winged warbler ranges west to central Iowa in migration, and in the lower Mississippi Valley is much less abundant in spring than in fall.

Late dates of fall departure are: Minnesota--Minneapolis, September 30. Wisconsin--Madison, October 11. Ontario--Point Pelee, September 2. Ohio--Ellsworth Station, September 23. Michigan--Ann Arbor, October 6. Indiana--Lyons, September 27. Illinois--Chicago, October 7. Missouri--La Grange, September 30. Kentucky--Versailles, September 25. Tennessee--Athens, September 29. Louisiana--New Orleans, September 25. Mississippi--Gulfport, October 8. Massachusetts--Danvers, September 7. New York--Brooklyn, October 2. Pennsylvania--Jeffersonville, October 2. District of Columbia--Washington, September 14. West Virginia--French Creek, September 15. North Carolina--Piney Creek, October 3. South Carolina--Chester, September 22. Georgia--Atlanta, October 9. Alabama--Greensboro, October 4.

Early dates of fall arrival are: Mississippi--Bay St. Louis, July 23. District of Columbia--Washington, August 8. Virginia--Naruna, August 23. North Carolina--Highlands, August 15. South Carolina--Charleston, August 20. Georgia--Athens, August 14. Alabama--Greensboro, August 11. Florida--Pensacola, August 14. Costa Rica--San José, September 15. Colombia--Bonda, September 6.

_Casual record._--One reported seen at Fort Thorn, N. Mex., in April 1854 by Dr. Joseph Henry. Since no specimen was taken this remains on the hypothetical list for the State.

_Egg dates._--Massachusetts: 14 records, May 27 to June 24; 9 records, May 30 to June 7, indicating the height of the season.

Michigan: 33 records, May 13 to June 10; 18 records, May 17 to 30.

New York: 6 records, June 3 to 24.

New Jersey: 7 records, May 25 to June 5 (Harris).

VERMIVORA PINUS (Linnaeus)

BLUE-WINGED WARBLER

PLATES 12, 13

HABITS

Bagg and Eliot (1937) write: "According to Wilson, this species was discovered by William Bartram, who gave it the descriptive name _Parus aureus alis caeruleis_ (Blue-winged Golden Tit), and sent a specimen to 'Mr. Edwards' by whom it was drawn and etched. Edwards suspected its identity with the Pine Creeper of Catesby: hence its present inappropriate name, _pinus_." As there are other warblers whose wings are more distinctly blue, those of this warbler being only bluish gray, the old familiar name, blue-winged yellow warbler, which stood for many years, seems more appropriate and more truly descriptive.