Part 7

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.