Life histories of North American wood warblers, Part 1 (of 2)

Part 9

Chapter 93,878 wordsPublic domain

On June 16, at 6.30 p. m., when the young were three days old, a downy puff appeared between the shoulders, wing quills being dark. The strongest bird had the eyes partly open and the mouth wide open for food.

On June 18, at 7 p. m., the heads and bodies were no longer flesh-colored but were well enough covered to appear dark. The eyes were open. At a _cluck_ from me their mouths flew open. Both parents fed them with green-colored larvae. When the male rested a moment on a brier above the nest, the female flew down and drove him away, fed the young, re-appearing with excrement in her beak, which was carried in an opposite direction from the regular approach via maple bough and poplar sapling. The male fed the young from a mouthful of very minute larvae or eggs, which were gathered from the silken nests in the unfolding leaves of a nearby poplar; after this (7.30 p. m.) the female covered the young for the night.

On June 20, at from 6.50 to 7.35 p. m., the young had been seven days in the nest. They were well feathered and of a yellowish-green cast, the short tails being tipped with yellow. The parents were more suspicious. The female came to the maple bough with something in her beak and flew down to the briers and back again several times before she dropped to the edge of the nest and fed her young. The male appeared immediately but swallowed a green grub himself upon discovery of me twenty-five feet away. The female came again in five minutes with a brownish object in her bill, but appeared more timid and refused to drop to the nest until the male set her an example of courage.

On June 21, at 6.12 p. m., the young were fully fledged in green plumage above and dirty yellow beneath. They showed fear of me for the first time, eyeing me in the same manner as the parent bird when on the nest. They were evidently ready to vacate at a moment's notice or hasty movement on my part. The parents appeared, scolding rapidly. The female fed the young as soon as I retired to my old stand under a bush, with a rather large green grub (6.20 p. m.) and flew out to the top of a blackberry bush, followed immediately by the topmost fledgling. It could do little more than run. The adults flew to within a yard of my head, making a great outcry, and in the midst of the excitement the remainder of the young vacated the nest with feeble _chips_. The male gave his attention to them, while the female followed me as I beat a hasty retreat to enable them to collect their little family before dark. Eight days had elapsed since incubation was completed, and it is not at all unusual for the young of this species to leave the nest while so tiny and ragged.

_Plumages._--Dr. Dwight (1900) calls the natal down "mouse-gray," and describes the juvenal plumage, in which the sexes are alike, as, "entire body plumage olive-yellow darkest on the back and throat. Wings and tail slate-gray largely edged with plumbeous gray, the tertiaries and coverts with olive-yellow; the greater and median coverts tipped with white, yellow tinged. Rectrices largely white. Lores dusky."

A partial postjuvenal molt begins early in July, involving the contour plumage and the wing coverts, but not the rest of the wings or the tail. This molt produces the first winter plumage in which the sexes are very much alike, the female being duller in color, especially the streak through the eye, and having less yellow on the crown. Dr. Dwight (1900) describes the first winter male as "above, bright olive-green, lemon-yellow on the crown veiled by greenish tips. Below, bright lemon-yellow, the crissum white or merely tinged with yellow. Transocular streak black. Wing coverts plumbeous gray, edged with olive-green, the greater and median tipped with white, yellow tinged, forming two broad wing-bands."

The birds are now practically adult in plumage. The first and subsequent nuptial plumages are acquired by wear, which produces little change beyond removal of the greenish tips. Subsequent winter plumages are acquired by a complete postnuptial molt each July.

The interesting hybrids between this and the golden-winged warbler are discussed on pages 3 and 4. Kumlien and Hollister (1903) mention a probable mating of this with the Nashville warbler.

_Food._--Nothing seems to have been published on the food of the blue-winged warbler beyond that mentioned above as food given to the young, which is doubtless eaten by the adults as well. It is apparently wholly insectivorous, seeking its food near the ground in the weed patches and underbrush where it lives and among the lower branches of the trees in its haunts. Probably any small insects that it can find in such places, as well as their larvae and eggs, including many small caterpillars, are eaten. Small grasshoppers and spiders are probably included. Prof. Aughey (1878) observed it catching small locusts in Nebraska. It is evidently a harmless and a very useful bird in destroying insects that are injurious to foliage.

_Behavior._--Dr. Chapman (1907) writes: "It is rather deliberate in movements for a Warbler, and is less of a flutterer than the average member of the genus _Dendroica_. Some of its motions suggest those of the tree-inhabiting Vireos, while at times, as the bird hangs downward from some cocoon it is investigating, one is reminded of a Chickadee." And he quotes Burns as follows:

Perched inconspicuously near the top and well out on the branchlets of a tree or sapling, preferably facing an opening, if in a thicket; it is in itself so minute an object as to be passed unseen by many, more especially as it is much less active than most of our Warblers. With body feathers puffed out to a delightful plumpness, except for the backward sweep of the head while in the act of singing, it remains motionless for quite a while. When it moves it is with a combination of nervous haste and deliberation, and its song may be heard from quite another part of the landscape with no apparent reason for the change. While it has its favorite song perches, it is quite a wanderer and not infrequently sings beyond possible hearing of its brooding mate, but oftener within fifty to two hundred feet of the nest.

_Voice._--Aretas A. Saunders contributes the following study of the songs of this warbler: "The territory song of the blue-winged warbler consists of two long, buzz-like notes, the second usually lower in pitch than the first and rougher in sound, _bzzzzzzz-brrrrrrrr_. The pitch interval between the two notes varies from one tone to four and a half tones, but the smaller intervals, one tone and one and a half tones, are much commoner. The second note is lower in pitch than the first in about 75 percent of my records, and higher in most of the others. In a few songs the second buzz is a double note, and one may hear both lower and higher notes from a medium distance, only the lower from a greater distance, and only the higher when very near the bird.

"The pitch is not high as compared to other warblers, ranging from C´´´ to D´´´´, one tone more than an octave. The territory song commonly begins on some note from A´´´ to C´´´´. It varies in time from 1-1/5 to 1-4/5 seconds, the first note being either equal to or shorter than the second. The second note is often twice as long as the first. In some songs the second note is broken into two notes, and in one record it is in four short notes, so that the song is essentially like that of the golden-winged warbler.

"After the birds have been on the breeding grounds for a week or two, singing of the nesting song begins. This song has the same buzz-like quality as the other, but it is exceedingly variable, considerably longer, and hardly ever twice alike. The song often begins with a series of short notes, like _tsit tsit tsit_, or contains such notes somewhere in the middle. There are usually long buzzes that change pitch by slurring upward or downward. On one occasion, I found a bird that sang a territory song and four different nesting songs. Often the nesting song is sung in flight. By June this song is heard about as frequently as the territory song, and in late summer, after the molt, it is the one most commonly heard.

"The song of this bird is heard from its arrival in spring until early July, when it ceases for a time. It is usually revived in late July or early August, and from then on may be heard fairly frequently until the birds depart about the last of August."

In his notes sent to Dr. Chapman, Burns describes the song as, "a drowsy, locust-like, _swe-e-e-e-e ze-e-e-e-e_, the first apparently inhaled and the last exhaled. * * * Another song heard on the first day of arrival, on one occasion, uttered by several males in company, possibly transients here, and may be the mating song, suggests the Chickadee's _che-de-de-e_, _che-dee-e_, and _che-de-de-dee_, uttered repeatedly in one form or other in excitement, and while running out on the branchlets. The call and alarm note is a rather weak _chip_." Dr. Chapman (1912) records a longer song, heard later in the season as "_w[=e][=e]-ch[)i]-ch[)i]-ch[)i]-ch[)i], ch[=u]r, ch[=e][=e]-ch[=u]r._"

Francis H. Allen tells me that the final note, _ze-e-e-e-e_, as rendered by Burns, "is really a very rapid series of _pips_, as if the bird had lips like ours and vibrated them by forcing the air through them--in other words, giving a sort of avian Bronx cheer, but high in pitch. The individual pip notes are clear, but the effect of the rapid succession is somewhat buzzy."

The songs of the hybrid forms may be like the song of either parent form, more often like that of the goldenwing, or a mixture of the two.

The flight song, as heard by Frank A. Pitelka, is recorded as follows:

_tsee-_ _zweé-_ _zweé_ _tzip-_ _tzip-_ _zee-zee-zee-zee-zee-zee-_ _zee-zee-zee-zee-zee-zee-_

The song of the blue-winged warbler is one of the high-frequency songs; Albert E. Brand (1938) gives the approximate mean as 7,675, the highest note about 8,050 and the lowest note about 7,125 vibrations per second; this compares with an approximate mean for the black-poll warbler of 8,900 vibrations per second, the highest frequency of any of the wood warblers, and an average for all passerine birds of about 4,000 vibrations per second.

_Field marks._--A small warbler with a greenish olive back, yellow forehead and under parts, with a black line through the eye and two white wing bars, is a blue-winged warbler. The female is merely more dull in coloration than the male, and the young even duller. The hybrids between this and the golden-winged warbler are more puzzling, but in a general way they can be recognized; a nearly typical blue-winged warbler with a black throat is probably a Lawrence's warbler; and a golden-winged warbler without a black throat or cheek and with a variable amount of white and yellow on the under parts and in the wing-bars, is probably a Brewster's warbler. But there is an immense amount of individual variation between the two species, due to frequent crossing.

_Fall._--Most of the blue-winged warblers move southward during August and September, though a few may linger in the southern part of the breeding range into October. Professor Cooke (1904) says: "Most of the individuals of the species migrate across the Gulf of Mexico, apparently avoiding Florida on the east and Texas and Vera Cruz on the west, as there is no record of the occurrence of this warbler in fall in Texas, and but one in Florida--that of a bird taken at Key West August 30, 1887." But this remains to be proved.

Alexander F. Skutch writes to me: "This is another very rare migrant in Central America. It has been recorded only a few times in Guatemala and apparently not at all in Costa Rica. I have seen it only once, on the Finca Mocá, Guatemala, on October 30, 1934."

Very little seems to be known about its winter distribution and still less about its winter habits.

DISTRIBUTION

_Range._--Eastern United States to Panamá.

_Breeding range._--The blue-winged warbler breeds =north= to southeastern Minnesota (Lanesboro); southern Wisconsin (Mazomanie, Prairie du Sac, and Glarus); northeastern Illinois (Rockford, Deerfield, and La Grange); southern Michigan (possibly Hastings, and Ann Arbor); northern Ohio (Toledo, Lakeside, Cleveland, and Austinburg); southern Pennsylvania (Carlisle); southern New York (Ossining and Whaley Lake); and Massachusetts (Springfield and Sudbury). =East= to eastern Massachusetts (Sudbury and Lexington); Connecticut (Westfield and Saybrook); Long Island (Mastic and Oyster Bay); New Jersey (Demarest, Morristown, and Elizabeth); southeastern Pennsylvania (Tinicum and Berwyn); probably occasionally in northern Maryland (Cecil County and Sabillasville); eastern and central Ohio (Canfield and Columbus); east-central Kentucky (Berea); central Tennessee (Nashville and Fall Creek); and central northern Georgia (Young Harris). =South= to northern Georgia (Young Harris, Margret, and Atlanta); northeastern Alabama (Long Island); central Tennessee (Wildersville); and northwestern Arkansas (Pettigrew and Winslow). =West= to northwestern Arkansas (Winslow and Fayetteville); west-central Iowa (Warrensburg); eastern Iowa (Lacey, Grinnell, Winthrop, and McGregor); and southeastern Minnesota (Lanesboro). The blue-winged warbler has occurred in summer west to eastern Kansas (Emporia and Leavenworth); central-southern and eastern Nebraska (Red Cloud, Plattsmouth, and Omaha); western Iowa (Sioux City); and north to Minnesota (Minneapolis); southern Ontario (Point Pelee, Strathroy, and West Lake); central New York (Penn Yan and Auburn); and southern New Hampshire (Manchester).

_Winter range._--The principal winter home of the blue-winged warbler seems to be in Guatemala, though it has been recorded in winter from the Valley of Mexico; Puebla (Metlatoyuca); Veracruz (Tres Zapotes); to eastern Nicaragua (Río Escondido and Greytown). There is one winter record each from Costa Rica (Bonilla), Panamá (Port Antonio), and Colombia (Santa Marta Region).

On January 6, 1900, a dead blue-winged warbler (apparently dead from starvation) was picked up in Bronx Park, New York. It had only recently died and in all probability was the bird seen on December 10, in the same region.

_Migration._--Late dates of spring departure are: Colombia--Santa Marta Region, March 21. Veracruz--Jalapa, April 7. Florida--Pensacola, April 25. Alabama--Guntersville, May 2. District of Columbia--Washington, May 30. Louisiana--Monroe, April 27. Texas--San Antonio, May 12.

Early dates of spring arrival are: Florida--Pensacola, April 4. Alabama--Shelby, April 4. Georgia--Atlanta, March 26. North Carolina--Arden, April 18. District of Columbia--Washington, April 23. West Virginia--Wheeling, April 23. Pennsylvania--Germantown, April 25. New York--Yonkers, April 26. Massachusetts--Lexington, May 6. Mississippi--Bay St. Louis, March 13. Louisiana--New Orleans, March 23. Arkansas--Winslow, April 2. Tennessee--Nashville, April 7. Kentucky--Eubank, April 10. Illinois--Springfield, April 29. Ohio--Columbus, April 22. Michigan--Ann Arbor, May 1. Missouri--St. Louis, April 17. Iowa--Grinnell, April 28. Wisconsin--Reedsburg, April 30. Minnesota--Lanesboro, May 7. Texas--Cove, March 27. Kansas--Onaga, April 26.

Late dates of fall departure are: Minnesota--Lanesboro, September 1. Wisconsin--Elkhorn, September 19. Iowa--Giard, September 20. Missouri--Monteer, September 17. Arkansas--Winslow, September 18. Louisiana--Monroe, October 7. Michigan--Jackson, September 13. Ohio--Oberlin, September 27. Indiana---Bloomington, September 28. Illinois--Chicago, September 29. Kentucky--Bowling Green, October 5. Tennessee--Memphis, September 11. Mississippi--Deer Island, October 13. Massachusetts--Belmont, September 6. New York--New York City, September 25. Pennsylvania---Jeffersonville, September 19. District of Columbia, Washington, September 14. West Virginia--French Creek, September 28. North Carolina--Reidsville, September 26. South Carolina--Huger, September 10. Georgia--Tifton, September 27. Florida--St. Marks, October 9.

Early dates of fall arrival are: District of Columbia--Washington, August 13. Georgia--Columbus, July 28. Alabama--Leighton, August 8. Florida--Key West, August 30. Mississippi--Gulfport, August 23. Texas--Cove, July 29. Tamaulipas--Matamoros, August 25. Costa Rica--Bonilla, September 8.

_Banding._--Few blue-winged warblers have been banded and recovered. A bird banded at Elmhurst, Long Island, on August 17, 1935, flew into a screened porch at Westbury, Long Island, on May 7, 1937. The two places are about 15 miles apart.

_Egg dates._--Connecticut: 30 records, May 25 to June 24; 20 records, May 29 to June 6, indicating the height of the season.

New Jersey: 40 records, May 16 to June 19; 29 records, May 22 to 30.

Pennsylvania: 27 records, May 28 to July 7; 14 records, May 28 to June 3 (Harris).

VERMIVORA BACHMANII (Audubon)

BACHMAN'S WARBLER

CONTRIBUTED BY EDWARD VON SIEBOLD DINGLE

HABITS

Bachman's warbler was discovered by Dr. John Bachman a few miles from Charleston, S. C., in July, 1833. According to Audubon (1841), who described and named in honor of his "amiable friend" the only two specimens taken, several other birds were seen soon after in the same locality.

More than half a century passed before the bird again appeared in America, this time in Louisiana. Charles S. Galbraith (1888), while securing specimens of warblers at Lake Pontchartrain for the millinery trade in the spring of 1886, took a single bird; in the two succeeding years he collected a number of additional specimens, 6 in 1887 and 31 in 1888. These birds were evidently migrating, for the 31 were all taken between March 2 and 20, and none could be found after the end of March. Chapman (1907) comments on Galbraith's first specimen: "This specimen, now in the American Museum of Natural History, is prepared for a hat-piece. The feet are missing, the wings are stiffly distended, the head bent backward in typical bonnet pose, and, had it not been for an interest in ornithology which led Galbraith to take his unknown birds to Mr. Lawrence for identification, this _rara avis_ might have become an unappreciated victim on Fashion's altar."

Since then the records have multiplied; but _bachmanii_ has always been an extremely local species, even in migrations, and breeds in primeval swamps in small colonies, which are few and far between. At the present writing, the bird is one of the very rarest of North American warblers. It has been an unattained ideal to the writer; yet, having heard much about its habits from the late Arthur T. Wayne and having visited with him the former breeding grounds, he has some consolation for not having met it in life.

Wayne (1901) took a specimen of this species on May 15, 1901, near Mount Pleasant, which was the first record for South Carolina since Dr. Bachman collected the type, and says: "I am positive that I have heard this song nearly every summer in the same localities where the male was found, but I always keep out of such places after April 10 on account of the myriads of ticks and red bugs which infest them. Then, too, such places are simply impenetrable on account of the dense blackberry vines, matted with grape vines, fallen logs piled one upon another, and a dense growth of low bushes."

_Spring._--From its winter home in Cuba Bachman's warbler enters the United States through Florida, and according to Howell (1932) the earliest date of arrival in that state is February 27. It has also been recorded from Louisiana on the same date (Chapman, 1907). The majority of individuals, however, cross to the United States mainland early in March; apparently the birds that summer in Alabama, Missouri, Arkansas, and Kentucky reach their breeding grounds by skirting the Gulf coast and continuing up the Mississippi Valley. They reach the vicinity of Charleston, S. C., in March and nesting begins at once, for Wayne (1907) found a nest on March 27 containing one egg and another on April 3 with five well-incubated eggs. He calls attention to the fact that Bachman's warbler therefore breeds earlier than the resident pine and yellow-throated warblers.

_Nesting._--Dr. Bachman did not discover the breeding grounds of this warbler, and it was more than 60 years before the first nests and eggs became known to science; Widmann (1897) found the bird breeding in the St. Francis River country of Missouri and Arkansas on May 13, 1897. The nesting area extended "over two acres of blackberry brambles among a medley of half-decayed and lately-felled tree-tops, lying in pools of water, everything dripping wet with dew in the forenoon, and steaming under a broiling sun in the afternoon." The first nest, which he describes as being 2 feet from the ground, "was made of leaves and grass blades, lined with a peculiar black rootlet; it was tied very slightly to a vertical blackberry vine of fresh growth and rested lightly on another, which crossed the former at a nearly right angle. From above it was entirely hidden by branchlets of latest growth, and the hand could not have been inserted without at first cutting several vines, overlying it in different directions."

Ridgway (1897) describes this nest as, "a somewhat compressed compact mass composed externally of dried weed- and grass-stalks and dead leaves, many of the latter partially skeletonized; internally composed of rather fine weed- and grass-stalks, lined with black fibres, apparently dead threads of the black pendant lichens (_Ramalina_, species?) which hang in beard-like tufts from button-bushes (_Cephalanthus_) and other shrubs growing in wetter portions of the western bottom-lands. The height of the nest is about 3-1/2 inches; its greatest breadth is about 4 inches, its width in the opposite direction being about 3 inches. The cavity is about 1-1/2 inches deep and 1-1/2 × 2 inches wide."

In 1906, Wayne (1907) found six nests of Bachman's warbler near Charleston, S. C., from two of which the young had flown. "The swamp in which this warbler breeds is heavily timbered and subjected to overflow from rains and reservoirs. The trees are chiefly of a deciduous character, such as the cypress, black gum, sweet gum, tupelo, hickory, dogwood, and red oak. In the higher parts of the swamp short-leaf pines, water oaks, live oaks, and magnolias abound. The undergrowth is chiefly cane, aquatic bushes, and swamp palmetto, while patches of blackberry brambles and thorny vines are met with at almost every step." The first two nests, found on April 17, are described as follows:

The first nest was placed upon a dead palmetto leaf, being supported by a small aquatic bush, and was completely hidden by a living palmetto leaf which overhung the nest, like an umbrella. It was in a dense swamp, two feet above the ground, and contained four pure white eggs, almost ready to be hatched.

The second nest, which was within one hundred yards of the first one, was built in a bunch of canes (_Arundinaria tecta_), and supported by a palmetto leaf. This nest was three feet above the ground, in a comparatively dry situation, and contained four pure white eggs in an advanced stage of incubation. * * *

The two nests are similar, being constructed of fine grass, cane leaves, and other leaves, the latter skeletonized. The second nest, taken April 17, is 6-1/2 inches high, 6 inches wide, 2 inches wide at rim, and 2 inches deep. It is composed almost entirely of dead cane leaves, a little Spanish moss (_Tillandsia usneoides_), and a few skeletonized leaves. * * *

The female is a very close sitter; indeed so close that I found it necessary to touch her before she would leave the nest. This habit was the same in both females.

The other nests were in low bushes, vines, or canes.