The Newfoundland Yellow Warbler was not observed about Hooper Bay, but as soon as I reached the willows near the mouth of the Yukon River I found it common, and also of like distribution at the other stops that I made on the river as far up as Mountain Village.* * *The nest of the Newfoundland Yellow Warbler in the Yukon delta is placed usually in a small willow from two to six feet above the ground. The foliage in early July is but partly unfolded, for the alders are yet in their golden curls and the willows in their silver catkins, so the nest is rather conspicuous.The bird chooses a pronged fork usually with not more than three or four shoots, and in this form constructs its beautiful, trim nest, which is made of plant down and inner bark shreds, all circularly woven and firmly rimmed.
The Newfoundland Yellow Warbler was not observed about Hooper Bay, but as soon as I reached the willows near the mouth of the Yukon River I found it common, and also of like distribution at the other stops that I made on the river as far up as Mountain Village.* * *
The nest of the Newfoundland Yellow Warbler in the Yukon delta is placed usually in a small willow from two to six feet above the ground. The foliage in early July is but partly unfolded, for the alders are yet in their golden curls and the willows in their silver catkins, so the nest is rather conspicuous.
The bird chooses a pronged fork usually with not more than three or four shoots, and in this form constructs its beautiful, trim nest, which is made of plant down and inner bark shreds, all circularly woven and firmly rimmed.
Baird, Brewer, and Ridgway (1874) say: “The notes of Mr. Kennicott and the memoranda of Messrs. McFarlane, Ross, and Lockhart attest the extreme abundance of this species in the farthest Arctic regions. In nearly every instance the nests were placed in willows from two to five feet from the ground, and near water. In one instance Mr. Ross found the eggs of this species in the nest ofTurdus swainsoni, which had either been deserted or the parent killed, as theeggs were in it, and would probably have been hatched by the Warbler with her own.”
As evidence of the late migration of this subspecies, Robie W. Tufts writes to me from Nova Scotia: “The latest date of departure which appears to be normal is October 7, 1936, though they generally leave during the second week of September. On November 25, 1929, a female was collected by me at Wolfville. The bird was searching for food very actively and its general behavior was decidedly abnormal. The bird’s body showed slight traces of emaciation.” Birds that have been recorded in Massachusetts as late as September 30, long after our local breeding birds have left, were probably of this subspecies.
DENDROICA PETECHIA RUBIGINOSA (Pallas)
ALASKA YELLOW WARBLER
HABITS
This subspecies was formerly supposed to range throughout most of Alaska, but its breeding range is now understood to be restricted to the coast region of southern Alaska and British Columbia, from Kodiak Island (the type locality) southward to Vancouver Island. It migrates through California to Mexico and Central America, and probably spends the winter in South America. In El Salvador, according to Dickey and van Rossem (1938), “this race was found only as a fairly common spring migrant through the upper levels of the Arid Lower Tropical. As withD. p. aestivathe winter range undoubtedly lies farther to the south. It is notable thatrubiginosaoccurs at somewhat higher elevation than the other three forms and was not found at all in the ‘tierra caliente.'” This race has been reported in Kansas and in central Texas, but these birds may have beenamnicola, which somewhat resemblesrubiginosaand which had not been accepted at that time.
Ridgway (1902) describes the Alaska yellow warbler as “similar toD. ae. aestiva, but slightly smaller and much duller in color. Adult male darker and duller olive-green above, the pileum concolor with the back or else becoming slightly more yellowish on forehead (very rarely distinctly yellowish on forehead and fore part of crown); wing-edgings less conspicuous, mostly yellowish olive-green, sometimes inclining to yellow on greater coverts. Adult female darker and duller olive-greenish above, duller yellow below.” He might have added that the chestnut streaks on the breast are narrower than inaestiva.
Nothing seems to have been published on the nest and eggs of the Alaska yellow warbler, nor on its habits, all of which probably do not differ materially from those of the species elsewhere in similar environment.
DENDROICA PETECHIA MORCOMI (Coale)
ROCKY MOUNTAIN YELLOW WARBLER
HABITS
This is another race that was described many years ago by H. K. Coale (1887) but has only recently been accepted by the A. O. U. Coale gave it its scientific name in honor of J. Frean Morcom and called it the western yellow warbler. The following remarks by Dickey and van Rossem (1938) tell the story very well:
The race of yellow warbler summering in the Great Basin and Rocky Mountain regions of the United States of late years has been generally overlooked and has been synonymized commonly withaestivaor, in part, withbrewsteri. Although not a well differentiated form, its characters are readily apparent in series, and there is no reason why it should not be accorded equal standing with the races currently recognized. The underparts of the males are heavily marked, and in this respectmorcomiis not distinguishable fromaestiva. Dorsally, however,morcomiis darker and less yellowish green, particularly on the interscapular region. The females are, age for age, more buffy (less yellowish) below and darker and more grayish above than the females ofaestiva. In comparison withbrewsteri,morcomi(particularly the bill) is larger, and the males are more heavily streaked below. The range ofmorcomiis the Rocky Mountain region of the United States, north to Wyoming and Idaho, west to the eastern slope of the Sierra Nevada, and south (in the western part of its range) to Mammoth, Mono County, California. We have not seen material from the southern Rocky Mountains; so we cannot state the southern limits in that region.
They call it a “common spring and fall migrant and winter visitant in the lowlands,” of El Salvador. “Dates of arrival and departure are August 1 and April 9.”
Angus M. Woodbury has sent me a copy of the manuscript for “The Birds of Utah,” by Woodbury, Cottam, and Sugden, from which I infer that the haunts, nesting, and other habits of the “western yellow warbler,” as they call it, do not differ materially from those of the well-known eastern bird. They say of its status in Utah: “This yellow warbler is a common summer resident from early May to late August, the vanguard sometimes reaching here in late April and stragglers sometimes lingering into September, the latest record being September 23. It is primarily a bird of the riparian growths along water edges, either of streams, ponds or lakes or irrigated areas, particularly of the valleys and lower canyons, but occurs higher in the canyons in suitable habitat up to at least 8,000 or 9,000 feet. It does not seem to be attracted to large trees such as cottonwoods, but seems to prefer the more leafy shrubbery and small trees of developmental stages in ecological succession. In migration, it sometimes leaves this niche and may occasionally be found elsewhere.* * *
“In nesting, it is usually found in a bush, chaparral or small tree stratum, seldom going to the ground or to the tops of trees. Its nestsare compactly woven cups generally placed from 3 to 10 feet above ground, sometimes 15 feet, in rosebushes, willows, choke cherries, hawk-berries, oaks, young cottonwood or boxelder trees, usually within a short distance of the water’s edge. The nest is usually composed of gray plant fibers, bark shreds or grasses and is usually lined with some downy substance such as cottonwood or willow cotton or hair.”
DENDROICA PETECHIA BREWSTERI Grinnell
CALIFORNIA YELLOW WARBLER
HABITS
The 1931 A. O. U. Check-List gives the breeding range of this subspecies as the “Pacific coast strip from western Washington south through Oregon and California, west of the Great Basin and southeastern deserts to about lat. 30° in Lower California.” It intergrades withrubiginosaon the north and withmorcomito the eastward, but exact boundaries are difficult to define. It seems to range well up into the mountains, for James B. Dixon tells me that he has found it nesting in Mono County, Calif., at altitudes of 6,500 to 9,200 feet.
Dr. Joseph Grinnell (1903) in an interesting study of western yellow warblers, bestowed the above name on the California bird, for which he gives the following subspecific characters: “ResemblingDendroica aestiva aestiva, from which it differs in smaller size, paler (or less brightly yellow) coloration, and, in the male, narrower streaking on under surface; differs fromDendroica aestiva rubiginosain much smaller size and yellower coloration, and fromDendroica aestiva sonoranain smaller size and much darker coloration.”
Spring.—Bothrubiginosaandbrewsterioccur in California and in Washington on migrations. As it is difficult to distinguish the two forms in life, some of the following remarks may refer to either or both of these two subspecies. Mrs. Amelia S. Allen writes to me that this species “is the latest of the warblers to arrive in the San Francisco Bay region for the breeding season. Sometimes they are here by April 8, but the average date is about April 18. At Lake Tahoe, the first week of June, breeding pairs were settled in the willows and migrants on their way farther north were migrating through.”
Samuel F. Rathbun says in his Washington notes: “Our experience with this species, based on many years of observation, is that the birds in the spring migration progress northward in a series of what may be called waves. Invariably the first noted will be one or two individuals, and these are heard for a short time only and evidently move on. Then there is a break of a day or so before the next are heard, a larger number. A period of a day, or perhaps two or three, may again elapse before the main body of birds arrive and they are heard on all sides.Common in and about the city at this period, it haunts the shade trees lining the streets and the fruit trees in the gardens, but is not at all partial to the outlying sections, except in the more cultivated areas and the orchards. It is essentially a bird of the older settled districts, wherever fruit trees and deciduous trees may abound.”
For May 6, 1924, he remarks, “These warblers drifted by all day, in ones and twos or threes, straggling, but, although seemingly widely separated, always within hearing distance of each other. At times there will be a break when apparently none are passing, then in the distance the song will be heard again, soon growing louder, as the bird draws nearer, following in the wake of others that have preceded him, his song in turn growing fainter in the distance after he has passed.”
Nesting.—The summer haunts and nesting habits of the California yellow warbler are generally similar to those of the eastern bird. Grinnell and Storer (1924) write:
Yellow warblers nest abundantly on the floor of Yosemite Valley. Some of the nests are in growths close to water, whereas others are located in brush tangles or other rank growths back some distance from the streams. A nest found June 7, 1915, may be taken as fairly typical. It was 52 inches above the ground in the crotch of a forking stem of a chokecherry which grew in a clump of the same plant, and was shaded by a black oak. As usual it was higher than wide outside, being 31⁄2inches in height by 3 to 31⁄4inches in diameter. The cuplike cavity was 13⁄4inches across at the top and the same in depth at the center. Shreds of bark and flat plant fibers were the principal materials used in construction, the lining being of horsehair and a few feathers.
One nest was “4 feet above the ground in a mountain lilac (Ceanothus integerrimus),” and another “was placed about 15 feet above the ground in a small pine tree growing at the margin of a pond. It rested on the next to the topmost whorl of branches and one side was against the slender trunk of the tree.”
In the Lassen Peak region, Grinnell, Dixon, and Linsdale (1930) report four nests in willows, one in a wax-berry (Symphoricarpos), one in a snowbush, and one fastened between stems of rose and willow at the edge of a clump of rose.
Eggs.—Three or four eggs seem to constitute the commonest set for the California yellow warbler. These are hardly distinguishable from those of the eastern bird, though they average, perhaps, more heavily marked. The measurements of 40 eggs average 16.6 by 12.4 millimeters; the eggs showing the four extremes measure18.3by 13.5, 17.8 by15.0,14.7by 12.2, and 16.3 by11.4(Harris).
Food.—Prof. F. E. L. Beal (1907) analyzed the contents of 98 stomachs of California yellow warblers, and found that the animal matter amounts to 97 percent of the food, consisting wholly of insects and a few spiders.
The largest item is Hymenoptera, which amounts to over 30 percent, almost half of which are ants. The remainder are small bees and wasps, some ofwhich are probably parasitic species, though none were positively identified.* * *Caterpillars, with a few moths, aggregate over 18 percent.Beetles form nearly 16 percent of the diet, and embrace about a dozen families, of which the only useful one is that of the ladybirds (Coccinellidae), which are eaten to a small extent. The great bulk of the beetle food consists of small leaf-beetles (Chrysomelidae), with some weevils and several others. One stomach contained the remains of 52 specimens ofNotoxus alamedae, a small beetle living on trees. Bugs (Hemiptera) constitute over 19 percent of the food, and are eaten regularly every month. Most of them consist of leaf-hoppers (Jassidae) and other active forms, but the black olive scale appeared in a number of stomachs. Plant-lice were not positively identified, but some stomachs contained a pasty mass, which was probably made up of these insects in an advanced stage of digestion.Flies seem to be acceptable to the summer warbler; they are eaten to the extent of nearly 9 percent. Some of them are of the family of the house fly, others are long-legged tipulids, but the greater number were the smaller species commonly known as gnats. A few small soft-bodied Orthoptera (tree-crickets), a dragon-fly, and a few remains not identified, in all about 5 percent, made up the rest of the animal food.
The largest item is Hymenoptera, which amounts to over 30 percent, almost half of which are ants. The remainder are small bees and wasps, some ofwhich are probably parasitic species, though none were positively identified.* * *Caterpillars, with a few moths, aggregate over 18 percent.
Beetles form nearly 16 percent of the diet, and embrace about a dozen families, of which the only useful one is that of the ladybirds (Coccinellidae), which are eaten to a small extent. The great bulk of the beetle food consists of small leaf-beetles (Chrysomelidae), with some weevils and several others. One stomach contained the remains of 52 specimens ofNotoxus alamedae, a small beetle living on trees. Bugs (Hemiptera) constitute over 19 percent of the food, and are eaten regularly every month. Most of them consist of leaf-hoppers (Jassidae) and other active forms, but the black olive scale appeared in a number of stomachs. Plant-lice were not positively identified, but some stomachs contained a pasty mass, which was probably made up of these insects in an advanced stage of digestion.
Flies seem to be acceptable to the summer warbler; they are eaten to the extent of nearly 9 percent. Some of them are of the family of the house fly, others are long-legged tipulids, but the greater number were the smaller species commonly known as gnats. A few small soft-bodied Orthoptera (tree-crickets), a dragon-fly, and a few remains not identified, in all about 5 percent, made up the rest of the animal food.
Only about 21⁄2percent of the food was vegetable matter, made up mainly of fruit pulp in a single stomach, one or two seeds and rubbish.
Rathbun (MS.) says that this warbler “shows some partiality for feeding on aphids, for we have many times watched it in an orchard carefully scanning the leaves on a tree for this insect.”
All other phases of the life histories of this and the following two subspecies do not seem to differ materially from those of the eastern yellow warbler and need not be repeated here.
Fall.—According to Rathbun’s notes, all the resident, breeding yellow warblers have departed from Washington “by the latter part of August, and in some seasons we have not heard the bird after the twenty-fifth; it is one of the few species that sing more or less during all of its sojourn here, and its song in late summer is almost as good as on its arrival in the spring. A break in the movement south of this species seems to occur about August 20 to 25. Then, early in September, the notes of the yellow warbler begin to be heard again. We have the idea that these may be of the Alaska yellow warbler.”
Mrs. Allen writes to me from Berkeley, Calif.: “Breeding birds leave the bay region in late July or early August; migrants from farther north begin to go through in September; the latest date on which I have seen them is October 16, 1920. I usually see them in the shade trees along the streets or in the woods when they come to bathe in my bird pool. But I have two records which show them in very different situations: September 18, 1933, on a hill slope that had been recently burnt over, a group of these warblers with horned larks and Savannah sparrows; and on September 25, 1941, at Point Reyes lighthouse, hunting for food in the low, dry lupines just inside the rocky point. One could not help wondering if they had just come to a landing place after a long flight over the ocean. They were in immature plumage.”
According to the 1931 Check-List, the California yellow warbler “migrates through eastern California, Arizona, and Lower California; winters sparsely in the Cape District of Lower California and south to Guatemala, Nicaragua, and Costa Rica.”
Winter.—Dickey and van Rossem (1938) record this warbler as a “winter visitant and spring migrant in the Arid Lower Tropical Zone,” in El Salvador. “The small Pacific coast race,brewsterii, is apparently relatively the least common of the four forms found in El Salvador; at any rate, the small number of specimens taken indicates that this is the case. Yellow warblers were common in January at Puerto del Triunfo and in February at Rio San Miguel, but unfortunately only one specimen was taken at each place. Whether all of these winter birds werebrewsteriandmorcomiis problematical.”
DENDROICA PETECHIA SONORANA Brewster
SONORA YELLOW WARBLER
HABITS
This is the palest of all the yellow warblers, one of the many pale races of the southwestern desert regions. Its breeding range extends from southeastern California, southern Utah, Arizona, and New Mexico to central western Texas, Sonora, and Chihuahua; and it winters from Mexico southward to Guatemala, Nicaragua, and Costa Rica.
It is best described by Ridgway (1902) as “similar toD. æ. æstiva, but much paler; adult male lighter and much more yellowish olive-green above, the back frequently (usually?) streaked with chestnut, pileum usually wholly clear yellow, lower rump and upper tail-coverts yellow, faintly streaked with olive-greenish; wing edgings all yellow; under parts lighter yellow than inD. æ. æstiva, and with chest and sides much more narrowly (often faintly) streaked with chestnut; adult female conspicuously paler than inD. æ. aestiva, the upper parts often largely pale grayish, the under parts usually very pale buffy yellow.”
Woodbury, Cottam, and Sugden (MS.) say of its status in southern Utah: “This race of yellow warbler is a breeder of the streamside fringes of willows, tamarix, and brush of various kinds along the San Juan and lower Colorado Rivers. It undoubtedly extends up the Colorado above the mouth of the San Juan, but how far it extends before yielding tomorcomihas not been determined. Data available are not sufficient to determine its nesting or migration dates or the length of its stay in Utah.”
Swarth (1914) calls it "a common summer visitant in southern and western Arizona, apparently confined almost entirely to the LowerSonoran river valleys, the Colorado and the Gila, with their tributaries.* * *I know of no breeding record of a yellow warbler from any point in Arizona north of the Mogollon Divide.” Mrs. Bailey (1928) says that “the lower Rio Grande in New Mexico apparently marks the most northern extension of the range of the Sonora Yellow Warbler. It is a common breeder at Mesilla,” which is in the southwestern part of the State.
We found the Sonora yellow warbler breeding commonly in the San Pedro Valley, near Fairbank, Ariz., and found several nests in a row of willows along an irrigation ditch. The nests, from 12 to 15 feet above the ground in slender trees, were not very different from those of the eastern bird, being made mainly of willow cotton interwoven with fine strips of inner bark, fine grasses, and plant fibers.
The eggs do not differ greatly from those of the species elsewhere, though what few I have seen are more faintly and finely speckled. The measurements of 40 eggs average 16.9 by 12.8 millimeters; the eggs showing the four extremes measure18.4by 13.1, 17.0 by13.6,14.9by 12.5, and 17.8 by11.4millimeters (Harris).
DENDROICA PETECHIA GUNDLACHI Baird
CUBAN YELLOW WARBLER
HABITS
The Cuban yellow warbler was originally described by Baird (1864) as a full species but is now regarded as a subspecies ofDendroica petechia. Ridgway (1902) describes it as “similar toD. p. petechia, but duller in color; adult male with upper parts much darker olive-green, the pileum usually concolor with the back, sometimes slightly more yellowish, very rarely tinged with orange-ochraceous, and wing-edgings less purely yellow; adult female usually duller in color than inD. p. petechia, often grayish olive-green, or even largely gray, above, and dull whitish, merely tinged here and there with yellow, beneath.”
Until recently, its range has been supposed to include only Cuba and Isle of Pines. Dr. Barbour (1923) says of its habits: “The Mangrove Canary, as the Cuban Yellow Warbler is called, is abundant wherever there are heavy high mangroves about the coast. I have found it abundant in eastern and western Cuba, and on the Isle of Pines as well. Gundlach reports it nesting in March. I incline to believe that May is more usual; and then the nest of grass, small feathers and woolly down, is placed in a fork on some horizontal mangrove limb. The whole life of the species is passed in the mangrove forests.”
Referring to the Isle of Pines, W. E. C. Todd (1916) writes: “This is a bird of the mangroves, to which it is apparently exclusively confined. It is accordingly most numerous along the coast and about the islands of Siguanea Bay, where the mangroves are so constant and pronounced a feature. Mr. Read has observed it along the Pine River also, but it is apparently a rare bird in the northern part of the island, judging from the dearth of records, and, indeed, it cannot be called a common bird in any locality as yet visited. Two nests were found, both in mangroves within a few feet of the water, during the third week in April, but as yet without eggs.”
More recently, this warbler has been found breeding on some of the lower Florida Keys. Earle R. Greene (1942) writes:
While exploring one of the Bay Keys in the Great White Heron National Wildlife Refuge off Key West, Florida, on June 15, 1941, with Roger Tory Peterson of the National Audubon Society, a male warbler, in full song, was located.* * *On June 26, the writer located it again on the same key, and on the 28th the male, female and nest were found. The last was in the top part of a red-mangrove tree (Rhizophora mangle) and was composed of seaweed and feathers; it contained one egg, white with brownish markings chiefly about the larger end. On July 10, the egg was found broken, apparently jabbed, possibly by a Red-wing nesting nearby. On July 16, the male bird was collected, and on the 30th the female.
Later (1944) he says: “Since then, a male and female were seen on June 16, 1942, on these same keys, and on July 14, 1942, an adult female was noted on the same keys. On August 6, 1942, a male and female, as well as an immature bird, being fed by an adult, were found on Big Mullet Key in the Key West Refuge, which is several miles from the Bay Keys. A letter received from Mrs. Frances Hames states that she found one bird, in song, on one of the Bay Keys on May 30, 1943. I consider it, therefore, a regular nester on certain keys in that area. Additional investigations may determine it as a common breeder.”
DENDROICA PETECHIA CASTANEICEPS Ridgway
MANGROVE YELLOW WARBLER
HABITS
Along both coasts of Baja California southward from about latitude 27° N., and along the Pacific coast of Mexico from Sinaloa to Guatemala, where that curious tree, the red mangrove (Rhizophora mangle), bathes its feet in salt water along the shores of bays, estuaries, and tidal creeks, this handsome yellow warbler makes its permanent home. The red mangrove extends its growth on these muddy shores by sending its curving branches outward and downward totake root again in the mud, thus forming an almost impenetrable tangle of roots and branches in an ever-widening band extending outward from the dry land. Its dense, dark foliage forms a low, gloomy forest of branches in which this well-named warbler finds a secure retreat and to which it is almost exclusively confined. It has not always been easy to obtain in these tangles, for Brewster (1902) says that—
during January, February, and a part of March, 1887, Mr. Frazer repeatedly visited all the mangrove thickets that he could find near La Paz, and made every effort to secure a good series of these Warblers, but he took only eight in all and did not shoot more than a pair in any one day. He notes the bird as “rare,” but adds that “its numbers Increased slightly in March.” It cannot be very numerous here at any time, for the total area covered by its favorite mangroves is very limited. Indeed, the place where most of his specimens were obtained “comprises only about two acres, through which winds a small creek, fordable at low tide; but at high water everything is submerged up to the lower branches of the mangroves. I always found the birds working near the surface of the water on the stems of the mangroves or hopping about on the mud, but the males resorted to the tops of the bushes to sing. Their notes are similar in general character to those of the Yellow Warbler.”
W. W. Brown was evidently more successful a little later in the season, for, in that same locality in May and June, he collected a large series of these beautiful birds for several American collections, mainly Col. John E. Thayer’s. He wrote to Colonel Thayer (1909):
I found the Mangrove Warbler a rare bird, but my previous experience with this species in Panamá, the Pearl Islands, and in Yucatan is what made me successful. I learned its song and alarm note in 1893. The first morning I went into the mangrove swamps of La Paz I whistled the song of the Yucatan species and the birds answered me; this is the secret of my success, for the species is very secretive in its habits. I found it so difficult to get that I offered fifty cents apiece to the duck hunters and others, including the local taxidermist, but they all failed to get it! By covering eight miles of territory I generally managed to get four or five. Sometimes when I shot one It would fall in the mangroves, with a tide running fast. Under such conditions it generally took a long time to find it, and a great deal of cutting with the machete.
Referring to the form found in El Salvador, Dickey and van Rossem (1938) remark: “To add to the difficulties in the path of the collector, the brown and yellow plumage of the males blends perfectly with the dead or dying mangrove leaves which are kept in continual motion by the sea breeze.”
Nesting.—Brown sent Colonel Thayer (1909) three nests of the mangrove warbler, only one of which contained a set of three eggs. Of this he says: “The nest with eggs is made (and the others resemble it very much) of light green fern down, cobwebs, and light-colored dried grasses, with a few white feathers plastered on the outside. It is beautifully lined with feathers. It is not so perfectly shaped or so well made as the Yellow Warbler’s nest.”
There are now six beautiful nests of this warbler in the Thayer collection in Cambridge, all collected by Brown near La Paz on dates ranging from May 15 to June 2; all were placed in the red mangroves, either on horizontal branches, mostly near the ends, or in forks; the heights from the ground or water varied from 2 feet to 10 feet. The largest and handsomest nest was 10 feet up on a horizontal branch; it is a very neat, compactly woven cup, made of soft, fine, light buff plant fibers, mixed with plant down, green moss that looks like down (probably the “light green fern down” referred to above oralgae), a few gray lichens and many whitish flower clusters; it is lined with very fine fibers, apparently from the mangroves, and plenty of feathers; it measures externally 3 inches in diameter and 21⁄2inches in height; the inner diameter at the top of the in-curved rim is 13⁄4inches and the cup is near 2 inches deep. The smallest nest measures only 21⁄4inches in outside diameter. The shallowest nest is only 11⁄2inches high and 11⁄4deep inside.
These nests are all works of art and quite distinctive; all the materials are smoothly and compactly felted, being tightly plastered together, as if glued on when wet. The light color and compactness suggest certain hummingbirds’ nests. Most of the nests seem small for the size of the birds.
Eggs.—Three eggs seems to form the usual set for the mangrove warbler; in the Thayer series there are five sets of three and one set of two. Ed. N. Harrison (MS.) says that “it seems that one egg is a set as often as two.” Most of the eggs in this series are ovate, but some are short ovate; they have only a very slight gloss. They are white or creamy white, speckled, spotted or blotched with shades of “mummy brown,” “bone brown,” “Prout’s brown,” or “clove brown,” with undertones of “light mouse gray,” “deep mouse gray,” “Quaker drab,” or “drab-gray.” The browns are frequently so dark as to appear almost black, but some eggs are spotted with lighter shades, such as “cinnamon brown” and “snuff brown.” On the more lightly marked types the most prominent markings are the grays, with only a few scattered brown spots. Often a loose wreath is formed around the large end, where the spots are usually concentrated.
The measurements of 32 eggs average 17.9 by 13.4 millimeters; the eggs showing the four extremes measure19.5by 13.2, 17.9 by14.6,17.0by 13.2, and 18.3 by12.9millimeters (Harris).
Plumages.—Although I have examined a large series of mangrove warblers, I have seen no downy young and no summer birds in juvenal plumage. But Dr. Chapman (1907) describes the young female as “above grayish olive-green, rump brighter; tail blackish, externally greenish, webs of all but central narrowly margined with yellow; wings and their coverts blackish, quills margined, coverts tipped withdull greenish; below whitish more or less washed or obscurely streaked with yellow, the under tail-coverts pale yellow.”
Young males in the fall are much like adult females, but brighter in color and often with traces of chestnut on the head. Apparently young males wear this femalelike plumage all winter; young males in March show a variable amount of chestnut on the head and throat, and show further progress toward maturity during April, May, and June, indicating a first prenuptial molt. A specimen described by Brewster (1902) is apparently undergoing this molt. “It has the head dull chestnut, very pale and mixed with whitish on the throat, mottled with greenish on the crown; the jugulum, sides of the neck and the middle of the breastwhitewith occasional small patches or single feathers of a pale yellow color and numerous fine, chestnut-rufous streaks on the breast; the remainder of the under parts pale primrose yellow mixed with whitish. The back, wings, and tail are nearly as in the adult female. The upper mandible is of the usual dusky horn color, but the basal half of the lower mandible of a pale flesh color. The plumage, generally, has a worn and faded appearance.”
This would seem to indicate that the first prenuptial molt is quite extensive, and that young birds become nearly adult after their molt. Adults probably have a complete postnuptial molt sometimes during the summer, but the following descriptions indicate that the prenuptial molt of adults is less extensive. Ridgway (1885) describes the type male, taken December 16, 1882, as follows: “Head rich chestnut, lighter or more rufous on the throat. Upper parts olive-green, the wings dusky, with broad greenish yellow edgings; outer webs of rectrices dusky, edged with yellowish olive-green, the inner webs chiefly primrose-yellow. Lower parts bright gamboge-yellow, the jugulum and breast with a few very indistinct and mostly concealed streaks of chestnut-rufous.” And of an adult female, taken December 29, 1882, he says: “Above grayish olive-green; wings grayish dusky, the feathers edged with olive-grayish; rectrices dusky, outer webs edged with olive-green, the inner with primrose yellow. Lower parts dull pale olive-yellowish.”
From Dr. Chapman’s (1907) descriptions of spring adults it appears that there is very little seasonal change. Male: “Head all around and throat reddish chestnut; back yellow olive-green, the rump brighter; inner webs of all but central tail feathers largely yellow; wings black margined with yellow; underparts, except throat, rich yellow faintly streaked with reddish brown.” Female: “Above olive green, much darker and greener than [M]; tail black the two outer feathers with large yellow patches on the inner web near the tip; wings black margined with greenish yellow; below uniform pale, dull yellow.”
Laurence M. Huey (1927), referring to the bird life of San Ignacio and Pond Lagoons, on the west coast of Baja California, states that mangrove warblers were found there—
in isolated pairs and gave evidence of early nesting by their singing and by the condition of the sex organs of the specimens collected. This warbler was one of the most interesting species observed. The song of the male was usually delivered from a hidden position amid the dense mangroves, though occasionally the bird was seen perched on a dry twig projecting above the level tops of the thicket. The song was pleasing in tone, and of good volume, suggesting that of the Yellow Warbler, but less shrill. Unlike the song of the Yellow Warbler, it was given with a steady rising inflection. The alarm note is a sharp chirp, audible at some distance even during a brisk wind. This note is uttered at intervals and always in the same tone, much as are the chipping notes of the Orange-crowned Warblers. In searching for food, Mangrove Warblers resemble others of the genusDendroicain their habit of searching each leaf and stem with most careful scrutiny. At times, however, they were seen to launch forth into the air, in true “flycatcher” fashion, after small insects. These aerial sallies were seldom for a distance of over 10 feet, and the bird nearly always returned to the same perch from which it started.
Enemies.—The following remarks by Dickey and van Rossem (1938) about the El Salvador race of this species are of interest:
As the entire lives of these birds are spent in an environment which renders them immune from attack by the great majority of the predators which harass species inhabiting the land forest, one is at first inclined to be surprised at their relative scarcity. Raccoons (Procyon) are extremely common in the mangroves and were often found prowling through the branches at night. They, as well as carnivorous iguanas, undoubtedly take toll of many nests, but aside from these two it is difficult to conjecture what natural enemy operates to limit the mangrove warbler population. Certainly no “saturation point” has been reached, for pairs may be separated by as much as a mile even in the areas which appear most favorable.
DENDROICA MAGNOLIA (Wilson)
MAGNOLIA WARBLER
Plates 26-28
HABITS
Wilson secured only two specimens of this pretty warbler, one of which was shot among some magnolia trees near Fort Adams, Miss. He gave it the scientific nameSylvia magnoliabut called it the black and yellow warbler. This stood for many years as the common name. Nuttall, who had seen it only occasionally in Massachusetts, regarded it as rare. Audubon, on the other hand, found it quite common and even abundant in several places, as we now know it to be. His lively plate of this beautiful bird, one of his best, has always been a favorite of mine; and it seems to me that in the magnolia warbler, more than in any one of the many beautiful species of American woodwarblers, are best combined daintiness of attire with pleasing combinations and contrasts of often brilliant colors. Particularly are these qualities apparent when this warbler is seen amongst the dark green firs and spruces of its summer home, where its brilliant array of colors are displayed to advantage as it flits about, sometimes within a few feet of us.
Spring.—From their winter quarters in Mexico and Central America, some magnolia warblers migrate straight across the Gulf of Mexico to the Gulf coast between Louisiana and western Florida; they seem to be accidental in Cuba and very rare anywhere in Florida. Another migration, probably of some importance, occurs along the coast of Texas from the mouth of the Rio Grande to Louisiana; I saw a few magnolia warblers in the great migration wave noted on an island in Galveston Bay on May 4, 1923. Professor Cooke (1904) remarks: “The dates of arrival of the magnolia warbler in spring furnish the best evidence yet available in support of the theory that birds migrating across the Gulf of Mexico do not always alight as soon as they reach the shore. The species is a common spring migrant from the Mississippi River to the Atlantic, between latitudes 37° and 39°. South of this district it becomes less and less common, except in the mountains, until in the Gulf States it is rare.” It is significant that the earliest date of arrival at Atlanta, Ga., is the same as at the lower Rio Grande in Texas, April 20.
William Brewster (1877) writes:
The Black-and-Yellow Warbler arrives in Massachusetts from the South about the 15th of May. During the next two or three weeks they are abundant everywhere in congenial localities. Willow thickets near streams, ponds, and other damp places, suit them best, but it is also not unusual to find many in the upland woods, especially where young pines or other evergreens grow thickly. Their food at this season is exclusively insects, the larger part consisting of the numerous species ofDiptera. The males sing freely, especially on warm bright mornings. They associate indifferently with all the migrating warblers, but not unfrequently I have found large flocks composed entirely of members of their own species, and in this way have seen at least fifty individuals collected in one small tract of woodland. By the first of June all excepting a few stragglers have left.
On its migration as well as on its breeding grounds the magnolia warbler seems to avoid the taller tree-tops and to prefer the lower levels in the forests and in the thickets along the borders of woodlands; it is sometimes seen in garden shrubbery and in orchards, where it adds a brilliant touch of color to the blossoming fruit trees. When it reaches its breeding haunts it prefers low hemlock thickets, or more especially, where these can be found, the dense thickets of small spruces or balsam firs that spring up thickly in old clearings, or grow profusely along the more open woodland paths; the density of the forest depths seems to be avoided in favor of the more open spaces.
In Allegany Park, N. Y., according to Aretas A. Saunders (1938); “Magnolia warblers seem to have territory and a definite singing location, but I have seen no animosity toward each other or other species of warblers, such as the black-throated green and blackburnian, birds that have very similar habits and live in the same habitat and sometimes sing regularly in the same tree.* * *Territories are evidently vertical as well as horizontal, that is measured in volume rather than area, so that a clump of big hemlocks furnishes space for several pairs and several species of hemlock-loving warblers.”
Courtship.—William H. Moore (1904) says: “During the mating season the males are pugnacious little fellows, and many fights do rivals have. They attack each other with much fierceness, seizing hold with their beaks, and hitting with half-opened wings they sprawl about on the ground, until thoroughly overcome. When pressing his suit to the female of his choice, the male displays his colors to great advantage, as they show in fine contrast among the bright green foliage of the trees.”
Nesting.—All the 14 or more nests that I have seen, in Maine, New Brunswick, Quebec, and Newfoundland, have been in small spruces or balsam firs growing in old clearings, in reclaimed boggy pastures, or along the edges of coniferous woods. These little trees were often less than 6 feet high and generally stood in dense thickets. The lowest nest I find recorded in my notes was only 12 inches above the ground in a tiny fir, and the highest was 8 feet up in a slender balsam in a thick clump of these trees in rather open woods; more nests were below 5 feet than above it. The nests usually rested on horizontal branches or twigs and against the trunk but in a few cases they were placed a few inches or a foot out on a branch.
Similar nesting habits seem to be characteristic of the magnolia warbler in other parts of northern New England, Nova Scotia, and southern Canada according to information received from others; and most of the nests have been placed at similar low levels, though Mr. Brewster (1938) found one near Lake Umbagog that was 25 feet from the ground. In this northeastern region an occasional nest has been found in a cedar, a larch, or a small hemlock, but at a height usually less than 5 feet.
In New York and Pennsylvania hemlock seems to be the favorite tree, and the magnolia warbler more often places its nest at a higher level and well out toward the end of a horizontal branch, where it is usually shaded and sometimes well concealed in dense foliage. Verdi Burtch, of Branchport, N. Y., wrote to Dr. Chapman (1907) that he found nests "in hemlocks usually on a horizontal limb from eight to twenty feet up and over an opening in the woods. Several nests were found in the top of little hemlock saplings from one to five feetfrom the ground. One nest was found by Mr. C. F. Stone in a birch sapling, this being the only instance to my knowledge of its nesting in a tree other than a hemlock.” He has sent me a photograph of a nest in a wild blackberry bush.
T. E. McMullen has given me the data for 14 nests of the magnolia warbler found in the Pocono Mountains, Pa.; 10 of these were located in hemlocks from 30 inches to 30 feet above the ground and from 6 to 12 feet out on the branches; one nest was 30 feet up and one 18, but the others were all less than 10 from the ground. The other 4 nests were in rhododendrons, in woods, or along the banks of creeks, and were from 2 to 3 feet up.
Edward A. Preble (Todd, 1940) says that “all but one of more than fifty nests of this warbler that R. B. Simpson has examined near Warren [Pa.] were placed in hemlocks. One nest was at the exceptional height of thirty-five feet; another was only a foot from the ground in some low hemlock brush.” Mr. Simpson’s other nest was in a witch-hazel, and Mr. Saunders reported one in a pin cherry, both under hemlocks.
The magnolia warbler is a poor nest builder; its nests are apparently carelessly built and are very flimsy affairs, much like poorly built nests of the chipping sparrow; and they are usually insecurely attached to their supports. Brewster (1877) gives the following good description of a typical nest: “The framework is wrought somewhat loosely of fine twigs, those of the hemlock being apparently preferred. Next comes a layer of coarse grass or dry weed-stalks; while the interior is lined invariably with fine black roots, which closely resemble horse-hairs. In an examination of more than thirty examples I have found not one in which these black roots were not used. One specimen has, indeed, a fewrealhorse-hairs in the lining, but the roots predominate. This uniform coal-black lining shows in strong contrast with the lighter aspect of the outer surface of the nest.”
Miss Cordelia J. Stanwood, of Ellsworth, Maine, who has sent me some elaborate notes on the magnolia warbler, gives me this description of one of her best nests: “In this some hay and the fine tips of cinquefoil served as a foundation, but the greater part of the nest consisted of a fine black, vegetable fibre, resembling horsehair. So much of this hair-like material was used that, when the rim was frescoed with down from the willow pod, a person looking at the dainty abode in its setting of fir twigs could see nothing but the jet-black lining and the fluffy, silvery plant-down around the throat of the nest. The structure was partly pensile, being bound with spiders' silk to the two branches at right angles to the main stem.
“The front part of the base rested on the branches beneath. It was placed in a small fir, 2 feet from the ground, surrounded by a growthof fir and gray birches.* * *The nests were about 2 inches wide at the top on the inside and 11⁄4deep. The wall at the top was3⁄4inch thick.””
A series of eight nests now before me vary considerably in size, compactness, manner of construction, and in the materials used. The largest two measure 4 inches and 33⁄4inches, respectively, in outside diameter, and the smallest ones measure from 23⁄4to 3 inches. The inner diameter seems to be more constant, varying from 13⁄4to 2 inches. All of my nests are shallow, hardly more than an inch deep internally in most cases. Some of them are fairly well made, but most of them are very flimsy and more or less transparent. The neatest nests have the sides and rims well built up with dry grass or weed stems of varying degrees of fineness and density. In some there is no grass, but the sides are well made of the very finest hemlock or larch twigs interwoven with fine, red, fruiting stems of mosses and many fine, black rootlets; they are often slightly decorated or camouflaged with a few weed blossoms or bits of wool or plant down. The lining of black rootlets is present in these and in all other nests of the magnolia warbler that I have seen; it seems to be characteristic of the species and will distinguish the nests from those of other warblers. This jet-black lining forms a fine background against which the handsome eggs are shown in striking contrast.
Miss Stanwood gives in her notes the following account of nest building: “The birds fly with much jolly chattering through the trees and examine any nesting sites that appear desirable. The dainty female, after fitting her little body into many spaces among the twigs, finds one that is entirely adapted to her prospective domicile, and the birds proceed to fashion a basketlike frame of long, fine potentilla or cinquefoil runners, or culms of fine hay. These they fasten to the twigs and needles around the selected space with spiders’ web, or tent caterpillar silk, leaving the long ends free. Around the top of the basketlike frame on the interior is laid a culm of hay in the form of an imperfect circle, which is secured to the frame with spiders’ silk; many of the long ends are then turned down within, or crumpled into the space for the foundation of the superstructure. In the frame is fashioned the cradle, which is symmetrical and cup-shaped on the inside, but may be formed like the bowl of a spoon on the outside, according to the space which it is designed to fill. The preferred lining materials appear to be a jet-black, hair-like vegetable fibre, and horsehair, but on occasion, the dull orange setae of the birdwheat moss, or the brown fruit stems of maples are used for this purpose.
“Both twittering birds bring the materials while it is damp, if possible, and place it, but being very timid, they work little while an observer is near. At such times the birds come silently, one at a time,deposit the bit of cinquefoil or hair-like fibre hurriedly, the female who is oftentimes less timid than the male, doing most of the modelling, turning around and around in the tiny dwelling and shaping it with her breast. Two birds that I timed carefully spent 4 days building their habitation, and another pair 6 days in doing the same work. The amount of time occupied by the task is determined by the abundance or scarcity of materials and the weather; continuous, heavy, cold and retard the work greatly.”
Eggs.—Four eggs almost always form a full set for the magnolia warbler, but sometimes there are only three and occasionally five. They vary in shape from ovate to short ovate, or rarely to elongate ovate, and are only slightly glossy. The ground color is white or creamy white and in some instances greenish white. Their markings vary considerably, some being very lightly speckled, while others are boldly spotted, blotched or clouded with “buffy brown,” “cinnamon-brown,” “Mars brown,” “Prout’s brown,” “mummy brown,” “Brussels brown,” “chestnut,” “auburn,” or “tawny-olive,” with occasional scrawls of “bay” or black, and with undertones of “vinaceous-drab,” “deep brownish drab,” or “Quaker drab.” There is a tendency for the markings to be concentrated at the large end, where they often form a wreath, or sometimes a solid cap. Many interesting effects are found on the boldly marked eggs, where the large brown blotches are superimposed on the drab undertones. The measurements of 50 eggs average 16.3 by 12.3 millimeters; the eggs showing the four extremes measure17.9by13.2,15.0by 12.0, and 15.8 by11.6millimeters (Harris).
Young.—The period of incubation for the magnolia warbler is said, by different observers, to be 11, 12, or 13 days, and it is evidently performed by the female only. Miss Stanwood tells me that incubation sometimes begins after the second egg is laid. One egg is laid each day until the set is complete. The young remain in the nest from 8 to 10 days, usually the latter. The eyes of the young are opening on the third or fourth day. On the sixth day, the feathers are breaking the sheaths, and by the eighth or ninth day the young are well feathered. The female does all the brooding of the young, of which Miss Stanwood writes in her notes:
“At first the mother bird covered the young much of the time, as the infant birds were fragile and the weather was cold and damp. Every few minutes the brooding bird moved back on the nest far enough to feed the nestlings regurgitated or digested food, and to cleanse the nest of biting pests such as ants, which might endanger the lives of the baby birds. The father bird sang gaily, far away and near at hand, throughout the long summer day. When he came to the nest with food, he flirted his tail, fluttered his wings, quivered all over and twittered very prettily to his mate, who responded in like manner.
“He presented his first tender moths and juicy caterpillars to the mother bird, who ate part of them, but the remainder she crushed and mixed with digestive juices in her mouth and placed well down the throats of the baby birds.
“The little ones were not many hours old before the male insisted on presenting to them a few tidbits himself; and in a few days the parents fed the young almost exclusively on fresh insect food, which grew larger and tougher as the days went by.”
She mentions two attempts of the parent birds to draw her away from their young: “Once I accidentally flushed a brooding magnolia. The bird disappeared into the underbrush, but soon attracted my attention to herself by calling from the top of a second-growth fir, a few yards from where her precious secret was concealed. Then she fell from branch to branch, striking the boughs with a thud, like a dead weight, and dragged an apparently helpless leg or wing over the ground, but always away from where her treasures were hidden. On another occasion, when I visited a family of magnolias that were quite ready to fly, the little ones spilled over the side of the cradle into the surrounding grasses and ferns. Both parent birds, with spread wings and tail, tumbled from all the seedlings in the vicinity and trailed around in widening circles, calling piteously. At last the male bird poised himself in air on fluttering wings between me and a callow youngster, but the moment I lessened the distance between us he vanished.”
Henry Mousley (1924) recorded his observations on two nests of magnolia warblers, and found that during a period of 15 hours, at one nest containing very young birds, the male fed the young 34 times and the female 58 times; the average rate of feeding was once in 9.8 minutes; the female did all the brooding for a total of 6 hours and 19 minutes; the faeces were eaten 9 times and carried away 17 times, about equally by each sex.
Margaret Morse Nice (1926) made a very elaborate study of the happenings at another nest; her account, containing many interesting observations, to which the reader is referred, is too detailed to be quoted here. Her table shows that she watched the nest for a total of 261⁄2hours, spread over a period of 9 days; during this time, the young were fed by the male 118 times and by the female 91 times; the average rate of feeding was once in 7.8 minutes; the female brooded 33 times for a total of 352 minutes; the faeces were eaten 8 times and carried away 38 times.
Aretas A. Saunders (1938) writes: “After the young have left the nest, they are much in evidence in the forests. As soon as this happens, whatever territory there was is abandoned. The young wander away, keeping together, and the parents care for them, feedingthem frequently for the first few days. Both sexes feed the young, but after a day or two only the male is likely to be in attendance. Young in this stage are easily located by the incessant hunger calls. These calls consist of three or four high-pitched notes,tsee tsee tu—tsee tsee tsee tu—tsee tsee, etc. I cannot distinguish the call made by young of this species from those made under similar circumstances by the young of the black-throated green and blackburnian warblers.”
I have also received from Mrs. Doris Huestis Speirs and from Mrs. Louise de Kiriline Lawrence very full reports on their observations at two nests of magnolia warblers in Ontario. Many of their observations were similar to those mentioned; however, the following should be noted here: Mrs. Lawrence found the incubation period to be about 11 days, incubation and brooding being by the female only. The young were fed by both parents by regurgitation for the first 3 days, and after that on solid food, mostly caterpillars; in 49 minutes, the male fed them 7 times and the female 5 times. During 51⁄2hours, the male ate or carried away the fecal sacks 15 times. The young left the nest on the ninth day after hatching, and were fed by their parents up to the twenty-fifth day after leaving the nest; after that they were seen feeding themselves. Mrs. Speirs kept an accurate record of the brooding periods, which were from 8 to 45 minutes in length, but seldom less than 20 minutes, the female leaving the nest for periods of from 3 to 15 minutes. At times she closed her eyes and seemed to doze; occasionally she rose and turned the eggs with her feet or bill. The presence of birds of other species approaching or flying over did not seem to disturb her but the movements of a red squirrel in the vicinity kept her alert. The story of this nest ended in tragedy; some predator destroyed all but one of the young, the female finally disappeared and eventually there was nothing in the nest but an unhatched egg. A sharp-shinned hawk had been seen flying over.
Plumages.—Dr. Dwight (1900) calls the natal down “sepia-brown,” and describes the juvenal plumage as “above, dark sepia-brown, soon fading, usually paler on the crown and obscurely streaked with clove-brown. Wings and tail dull black, chiefly edged with ashy or plumbeous gray, the secondaries, tertiaries and wing coverts with drab, two wing bands pale buff; the rectrices white on inner web of basal half. Below, pale sulphur-yellow, dusky or grayish on the throat, and streaked or mottled except on the abdomen and crissum with deep olive-brown. Lores and orbital region ashy brown.”
The amount of yellow on the under parts is quite variable, the youngest nestlings showing very little or none at all. The sexes are practically alike in the juvenal plumage, but become recognizable during the first fall.
The postjuvenal molt begins early in July and involves all the contour plumage and the wing coverts, but not the rest of the wings or the tail.
This produces the first winter plumages, in which the young of each sex closely resemble their respective adult counterparts at that season but the colors are all duller, the crown and back are browner, there is a dusky band on the upper breast, and the black streaking is paler or obscure.
Dr. Dwight (1900) says: “First nuptial plumage acquired by a partial prenuptial moult which involves most of the body plumage, the wing coverts and sometimes a few tertiaries, but not the rest of the wings nor the tail. Young and old become practically indistinguishable except by the wings and tail, especially the primary coverts, all of which are usually browner and more worn than in adults.” According to Dickey and van Rossem (1938) this takes place in El Salvador early in April and is completed very rapidly.
Subsequent molts of adults consist of a complete postnuptial molt in July and August and an extensive prenuptial molt in April, as described above. Dr. Chapman (1907) says that the adult male in the fall is quite unlike the spring male; “crown and nape brownish gray; eye-ring whitish [instead of white spot below and a white line behind the eye];* * *rump yellow; tail as in Spring; wing-covertstipped[instead of broadly marked and forming a conspicuous white patch] with white forming two white bars; below yellow, sides with partly concealed black streaks, upper breast with a faint dusky band.” The fall female differs in a similar way from the spring female, having a browner crown and the dusky band on the upper breast well developed, much as in the young male in the fall. The female is always much duller than the male in all plumages.
Food.—Ora W. Knight (1908) writes: “The food consists largely of beetles, grubs, flies, worms and similar insects. I have seen the birds prying frequently into the deformities on spruce and fir produced by a species of licelike insects (Adelges), and feel very sure that they do good work in destroying these pests, which are becoming very numerous in some sections of the State [Maine] and injuring the spruce and fir trees.”
W. L. McAtee (1926) praises its good looks as well as its usefulness by saying: “The beautiful Black and Yellow Warbler is a common summer resident of the higher parts of the Catskill and Adirondack regions, and breeds sparingly in local cool spots elsewhere in the State [New York].* * *So far as known its food in our region consists entirely of insects and associated creatures, as spiders and daddy-long-legs. Almost all of its known items of insect food are sorts injurious to woodlands. It takes weevils, leaf beetles,and click beetles, leaf hoppers, plant lice, and scale insects, sawfly larvae and ants, and caterpillars and moths. Surely a record of good deeds to match the excellence of appearance of this feathered gem.”
F. H. King (1883) reports from Wisconsin: “Of seventeen specimens examined, three had eaten four hymenoptera, among which were two ants; one, one moth; six, seventeen caterpillars; six, fifteen diptera; six, twelve beetles; and one, two larvae. Two tipulids were represented among the diptera.” Professor Aughey (1878) counted as many as 23 locusts, probably in nymphal stages, in the stomach of a magnolia warbler collected in Nebraska. And F. L. Burns (1915a) included this species with the Cape May warbler as feeding on cultivated grapes.
Behavior.—The magnolia warbler is not only one of the most beautiful—to my mind, the most beautiful—of wood warblers, it is one of the most attractive to watch. It frequents, especially on its breeding grounds, the lower levels in its forest haunts, where it can easily be seen. It is most active and sprightly in its movements as it flits about in the small trees or bushes, with its wings drooping and its tail spread almost constantly, showing the conspicuous black and white markings in pleasing contrast with the brilliant yellow breast, the gray crown, and the black back; it seems to be conscious of its beauty and anxious to display it. Its rich and vivacious song, almost incessantly uttered during the early part of the nesting season, attracts attention and shows the nervous energy of the active little bird. It is not particularly shy and is quite apt to show itself at frequent intervals, as if from curiosity. The female sits closely on her nest until almost touched, and then slips quickly off to the ground and disappears. But both of the parents are devoted to their young and quite bold in their defense, as mentioned above by Miss Stanwood. At the nest that Mrs. Nice (1926) was watching the warblers paid no attention to a red squirrel that several times came within 15 feet of the nest. “In general the relations of these warblers with other birds was not unfriendly; no attention was paid to passing Chickadees nor to Chewinks and Maryland Yellow-throats that nested near. The only birds towards whom the male showed animosity were a male Myrtle Warbler that he drove away both during incubation and while the young were in the nest, and the male of his own species who came to call July 2. On July 8 the female warbler gave short shrift to an inquisitive female Black-throated Green Warbler that seemed to wish to inspect the household.”
The intimate studies made by Mrs. Nice and Henry Mousley indicate that these warblers will tolerate a reasonable amount of human intimacy without showing too much timidity.
Voice.—My earliest impression of the song of the magnolia warbler was written in 1891 aswee-chew, wee-chewin full, rich notes. Later Iattempted to syllabilize it quite differently; once I wrote itswitter, switter, swirr, orswicher, swich, a-swirr. On another occasion it sounded likewheet, tit, chéw, orwheet, wheet, tit, chéw.
Mrs. Nice (1926) noted only two songs, “the day song and perch songweechy weechand the feeding and vesper songsing sweetwith its variationsing sing sweet. He used three different notes:titthe alarm note,kreethe love note, andeep, the significance of which I never fathomed.”
Gerald Thayer wrote to Dr. Chapman (1907):
The Magnolia belongs among the full-voiced Warblers, and is a versatile singer, having at least two main songs, both subject to much and notable variation. The typical form of the commoner song is peculiar and easily remembered:Weeto wecto weétee-eet,—orWitchi, witchi, witchi tit,—the first four notes deliberate and even and comparatively low in tone, the last three hurried and higher pitched, with decided emphasis on the antepenultweetorwitch. The other song has the same general character, and begins with nearly the same notes, but instead of ending with the sprightly, high-pitchedwéetee-eet', it falls off in a single perfunctory-sounding though emphatic note, oflowertone than the rest. In syllables it is likeWitti witti wét',—weetee weetee wúr.
He proceeds to mention some variations:
One such variant I have fixed in my own recollection by the syllablesTer-whiz wee-it; and another, almost unrecognizable, by the syllablesWeé-yer weé-yer wee-yer. Still another beginning likeWeechi wéech, ended with a hurried confusion of small notes, some low, some high. But throughout these and all the many other surprising variations I have heard about Monadnock, the characteristic tone-quality was preserved unchanged, and so were certain minor tricks, scarcely describable, of emphasis and phrasing. The tone is much like the Yellow Warbler’s and also the Chestnut-side’s, though distinctly different from either. In loudness it averages lower than the Yellow’s and about equal to the Chestnut-side’s.
Then he mentions a peculiar call note,tlep, tlep, a lisping note with a slight metallic ring, that reminded him of the siskin or of Henslow’s sparrow.
The following remarkable list of seven distinct songs recognized by Stewart Edward White (1893) is included because it represents either some very unusual variations or very keen observation:
1. Three notes followed by one lower:che-weech che-weech che-ó. 2. Three sharp clear whistles with a strongrsound, then a warble of three notes, the middle the highest, the latter clear and decisive:pra pra pra r-é-oo. 3. Two quick sharp notes followed by a warble of three notes, the middle the highest: the warble is soft and slurred:prút pút purreao. 4. A soft falsetto warble, different in tone from any other bird song:purra-ĕ-whuy-a. 5. Of the same falsetto tone uttered rapidly:prut-ut-ut-ut-ut. 5. A harsh note like, in miniature, the cry of a Jay:d kay kay kay. 7. A harshk-e-e-e-dl, the last syllable higher by a shade, quick, and subordinated to the first part. The alarm note is a sharpzeek.
Mr. Brewster (1877) has written his impression of the song in words as, “she knew she was right; yes, she knew she was right.”Elsewhere, he writes it: “Pretty, pretty Rachel.” The latter version seems to suggest the rhythmic swing of the song very well.
Francis H. Allen (MS.) gives me several somewhat similar renderings, and mentions a migrating bird that sang for a long time early one morning in the spruces and hemlock near his house: “It was such steady and unintermittent singing as I have seldom if ever heard from any other warbler, and the bird alternated very regularly between the first and second songs—weetle weetle weetle weet, thenwill´ you wée sip, orwill´ you will´ you wée sip, the latter song not so emphatic as usual and weaker than the other.” This alternation is not uncommon with some species of warblers, as the redstart, but I have no records of it for the magnolia. He also mentions a common call note, “a dry 2-syllabled note,tizic, a little suggestive, perhaps, of the song of the yellow-bellied flycatcher”, which he thinks has no counterpart among our warbler notes.
Aretas A. Saunders has lately sent me a full account of the song of this warbler, saying, in part: “The song of the magnolia warbler is a short one, commonly of six or seven notes, of a weak, rather colorless, but musical quality. My 49 records of this song show that the number of notes varies from 4 to 9, all but 8 of them being of either 6 or 7 notes. The 6-note songs usually consist of three, 2-note phrases. The first two are just alike, the 2 notes of each phrase on different pitches. The third phrase is either higher or lower in pitch, and frequently with the order of pitch from low to high or from high to low reversed.
“The majority of the songs have a range, in pitch, of two or two and a half tones, nearly always between A‴ and D‴′. A few songs range as much as three and a half tones, and may be as low as F‴ or up to E flat‴′, but the range for the species is only five tones.
“The songs are quite short, ranging from3⁄5second to 12⁄5seconds. Individual birds often sing two or three different songs, or vary songs by dropping or adding notes.
“The song period extends from the arrival of the bird in migration to late July or early August. The average date of the last song in 14 years in Allegany Park is August 1. The earliest is July 26, 1933, and the latest August 15, 1937.”
Enemies.—Dr. Friedmann (1929) mentions only a few cases in which the magnolia warbler has been imposed upon by the cowbird, but E. H. Eaton (1914), says that the cowbird “seems to make a specialty of presenting this Warbler with one or more of its eggs, generally puncturing the eggs of the Magnolia before leaving the nest.” However, it is probable that this warbler is a rather uncommon victim, perhaps because the cowbird is not particularly common in the places where the warbler breeds.
Harold S. Peters (1936) lists two lice,Degeeriella eustigma(Kellogg) andMyrsidea incerta(Kellogg), as external parasites on this warbler.
Field marks.—The adult magnolia warbler of both sexes is so conspicuously marked that it should be easily recognized. The gray crown, black back and cheeks, yellow breast and rump, the two broad white wing bars and the large amount of white in the tail, midway between the base and the tip, are all good field marks. The female is only a little less brilliant than the male. The young bird in juvenal plumage is quite different, but the position of the white in the tail is distinctive.
Fall.—When the young birds are well able to take care of themselves, they and their parents join the gathering throngs of warblers and other small birds in preparation for the southward migration. Brewster (1877) writes:
In Eastern Massachusetts this species occurs as a fall migrant from September 21 to October 30, but it is never seen at this season in anything like the numbers which pass through the same section in spring, and the bulk of the migration must follow a more westerly route. Its haunts while with us in the autumn are somewhat different from those which it affects during its northward journey. We now find it most commonly on hillsides, among scrub-oaks and scattered birches, and in company with such birds as the Yellow-Rump (Dendroeca coronata) and the Black-Poll (D. striata). A dull, listless troop they are, comparatively sombre of plumage, totally devoid of song, and apparently intent only upon the gratification of their appetites.
Brewster was probably correct in assuming that the main trend of the fall migration is more westerly. Milton B. Trautman (1940) says of the fall migration of the magnolia warbler at Buckeye Lake, Ohio: “A persistent search in mid-August always resulted in recording a few early transients, and by the last of the month several were seen each day. The numbers increased gradually through early September. From September 10 to 25 the greatest daily numbers were attained, and 50 to 125 birds a day were noted. The numbers were slightly higher than they were in spring. The fall transients frequented the same types of habitat as did the spring birds, except that more were found in brushy fields or pastures, especially those dotted or thicketed with hawthorn and wild plum.”