Life Histories of North American Wood Warblers, Part One and Part Two. Arthur Cleveland Bent
mated with a goldenwing and was successful in following the resulting brood of young birds until they had acquired their first winter plumage when, fulfilling Mendel’s Law, they were all in “the garb of Helminthophila leucobronchialis,” thus establishing beyond a doubt the hybrid nature of the bird. At the end of his paper, Walter Faxon (1913) relates a bit of interesting ancient history regarding these three species of Vermivora. He says:
In my paper published in 1911, after stating the different hypotheses proposed in order to explain the relations existing among the Golden-winged, Blue-winged, Brewster’s, and Lawrence’s Warblers I added, half in jest, that the only hypothesis left for a new-comer in the field was this: that the Golden-winged and the Blue-winged Warblers themselves were merely two forms of one species. Curiously enough, not long after this I found that this very opinion had been expressed, and in a most unexpected quarter: in a letter dated Edinburgh, Sept. 15, 1835, Audubon wrote to Bachman that he suspected the golden-winged warbler and the blue-winged warbler were one species! That Audubon at that early date, ignorant (as he was assumed to be) of the existence of Brewster’s and Lawrence’s warblers, and but superficially acquainted with the golden-wing, should suspect that two birds so diverse as the blue-wing and the golden-wing were one species seemed incomprehensible, and in the light of what we now know about these birds, his surmise seemed to presuppose an almost superhuman faculty of prevision.
As a possible explanation of Audubon’s letter I have only this to offer: in the winter of 1876–77 Dr. Spencer Trotter discovered in the collection of the Academy of Natural Sciences of Philadelphia a specimen of Brewster’s warbler without a label, the third specimen known up to that time; on the bottom of the stand was written in the autograph of John Cassin, “J. C., 20 October, 1862,” and also a badly blurred legend “Not from Bell.” An appeal to J. G. Bell elicited the response that he remembered shooting a peculiar warbler in Rockland Co., N. Y., about the year 1832—a warbler something like a golden-wing, but lacking, although in high plumage, the black throat of that species; a great many years afterward, he sold this specimen in Philadelphia but knew nothing of its ultimate fate. Dr. Trotter justly inferred that the Philadelphia Academy specimen was in all probability the very bird shot by Bell.
Now as Audubon was intimately associated with Bell, is it not possible that he had examined this example of Brewster’s warbler? In that case, seeing that this bird’s characters were in part those of the blue-wing, in part those of the golden-wing, he may have inferred the interbreeding of these two birds, and so (rather unwarrantably, it is true) their identity. If this be not the explanation of the passage in Audubon’s letter to Bachman I have no other to suggest.
When Audubon came to publish his account of the Golden-winged Warbler in 1839 (Ornithological Biography, 1839, 5, p. 154) he said not a word about its connection with the Blue-winged Warbler.
Recently Karl W. Haller (1940) described “a new wood warbler from West Virginia” from two specimens, male and female, which he collected on May 30 and June 1, 1939, respectively, at points 18 miles apart, and proposed for it the new name Dendroica potomac, Sutton’s warbler. These birds resemble the yellow-throated warbler in plumage but lack streaks on the sides. They also suggest the parula warbler in having a faint yellowish wash on the back and, in the male, “an almost imperceptible hint of raw sienna” on the upper breast. The male sang a song much like the parula’s, but doubled by repetition.
Two more Sutton’s warblers have been carefully observed in the field: one at the point where the type was collected on May 21, 1942, by Maurice Brooks and Bayard H. Christy (1942); the second about 18 miles to the westward on June 21, 1944, by George H. Breiding and Lawrence E. Hicks (1945). Another aberrant warbler has been described by Stanley G. Jewett (1944), who examined four specimens which show a curious intermingling of the plumage characters of the hermit and Townsend warblers.
[Author’s Note: Since the above was written, Kenneth C. Parkes (1951) has published a study of the genetics of the golden-winged—blue-winged warbler complex, to which the reader is referred.]
MNIOTILTA VARIA (Linnaeus)
BLACK-AND-WHITE WARBLER
Contributed by Winsor Marrett Tyler
Plates 1-3
HABITS
The black-and-white warbler is one of the earliest spring warblers to reach its breeding-ground in the Transition Zone. Most of the other members of this family arrive in or pass through the region in mid-May or somewhat later, according to the season, when the oaks are in bloom and the opening flowers attract swarms of insects.
The black-and-white warbler, however, owing to its peculiar habit of feeding on the trunks and the large limbs of the trees, does not have to wait for the bounty supplied by the oaks but finds its special feeding-ground well stocked with food long before the oaks blossom or their leaves unfold. It comes with the yellow palm warbler late in April, when many of the trees are nearly bare, and not long after the pine warbler.
Mniotilta is a neat little bird, dressed in modest colors, at this season singing its simple but sprightly song as it scrambles over the bark—the black-and-white creeper, Alexander Wilson calls it.
Milton B. Trautman (1940), speaking of the spring migration at Buckeye Lake, Ohio, shows that the male birds are preponderant in the earliest flights. He says: “The first spring arrivals, chiefly males, were noted between April 16 and 30, and between May 1 and 5, 2 to 15 birds, mostly males, could be daily noted. The peak of migration usually lasted from May 6 to May 18, and then from 3 to 42 individuals, consisting of a few old males and the remainder females and young males, were daily observed. On May 18 or shortly thereafter a decided lessening in numbers occurred, and by May 23 all except an occasional straggler had left.”
Courtship.—Forbush (1929) gives this hint of courtship, which resembles the activities of most warblers at this season: “When the females arrive there is much agitation, and often a long-continued intermittent pursuit, with much song and fluttering of black and white plumage, and much interference from rival males before the happy pair are united and begin nesting.”
Nesting.—The black-and-white warbler usually builds its nest on the ground, tucking it away against a shrub or tree, or even under the shelter of an overhanging stone or bank. The nest is generally concealed among an accumulation of dead leaves which, arching over it, hides it from above. It is made, according to A. C. Bent (MS.), “of dry leaves, coarse grass, strips of inner bark, pine needles and rootlets, and is lined with finer grasses and rootlets and horsehair.” I have seen a nest made chiefly of pine needles on a base of dry leaves.
Henry Mousley (1916), writing of Hatley, Quebec, mentions moss as a component part of the nest, and says of three nests that they were all “heavily lined with long black and white horse hairs,” a peculiarity of coloration mentioned in one of Mr. Bent’s nests. Thomas D. Burleigh (1927b) speaks of a nest in Pennsylvania “built of dead leaves and rhododendron berry stems, lined with fine black rootlets and a few white hairs.” H. H. Brimley (1941) describes an exceptional nest. He says: “There was no particular departure from normal in its construction except for the fact that it was lined with a mixture of fine rootlets and very fine copper wire, such as is used in telephone cables. Fragments of such cable, discarded by repair men, were found nearby where a telephone line ran through the woods.”
Cordelia J. Stanwood (1910c) speaks of a nest “built in a depression full of leaves, behind a flat rock. * * * The cavity was shaped on a slant, the upper wall forming a partial roof. * * * It looked not unlike a small-sized nest of an Oven-bird. On the inside, the length was 21⁄2 inches, width 11⁄2 inches, depth 2 inches. On the outside, length 31⁄2 inches, width 21⁄2 inches, depth 21⁄2 inches. Thickness of wall at the top of nest, 1 inch; at the bottom, 1⁄2 inch.” Henry Mousley (1916) gives the average dimensions of three nests as “outside diameter 33⁄4, inside 13⁄4 inches; outside depth 21⁄4, inside 11⁄2 inches.”
F. A. E. Starr (MS.) writes to A. C. Bent from Toronto, Ontario, that