Life Histories of North American Wood Warblers, Part One and Part Two. Arthur Cleveland Bent
March 25. South Carolina, April 1. Louisiana—New Orleans, March 30. Mississippi—Biloxi, March 31. Tennessee—Memphis, April 20. Texas—Point Bolivar, April 17.
Late dates of fall departure are: Texas—Kemah, September 27. Tennessee—Sulphur Springs, September 9. Mississippi—Gulfport, October 6. South Carolina—Charleston, October 10. Georgia—Savannah, October 18. Alabama—Greensboro, September 6. Florida—Pensacola, October 2; Sombrero Key (4 struck lighthouse November 10).
Dates of fall arrival are: Tamaulipas—Matamoros, August 29. Jamaica, October 1.
Casual records.—A specimen was recorded near Corsicana, Tex., on August 24, 1880; another was collected at Kearney, Nebr., on April 9, 1905; and one near Holly, Prowers County, Colo., on May 12, 1913.
Egg dates.—Florida: 3 records, May 7. Georgia: 35 records, May 4 to July 13; 19 records, May 29 to June 17, indicating the height of the season. South Carolina: 28 records, May 2 to June 30; 14 records. May 12 to June 12 (Harris).
HELMITHEROS VERMIVOROS (Gmelin)
WORM-EATING WARBLER
Plate 10
HABITS
The breeding range of the worm-eating warbler covers much of the central portion of the United States east of the prairie regions. Its center of abundance seems to be in the vicinity of Pennsylvania, but it breeds less abundantly northward to southern Iowa, New York, and New England and southward to Missouri and to northern Alabama and Georgia, as well as in much of the intervening wooded region, where it is essentially a woodland bird.
The distribution, migration, and habits of this warbler were but poorly understood by the early writers on American birds, and neither Wilson nor Audubon ever saw its nest; the latter’s description of the nest, probably from hearsay, is entirely wrong. Frank L. Burns writes to me: “Bartram neglected to list this species, although he had furnished the type to Edwards 35 years earlier, and from the information furnished by the youthful Bartram it doubtless received its name, which is a misnomer perpetuated by Gmelin in his Motacilla vermivora.” Mr. Burns says further on in his notes: “I searched for 10 seasons before I found my first nest, and oddly enough it was through the parent bird carrying a ‘worm’ to its young; nevertheless I have since thought that a more fitting name for the species would have been hillside or laurel warbler.”
Hillside warbler would not be a bad name for this bird, which shows a decided preference for wooded hillsides covered with medium-sized deciduous trees and an undergrowth of saplings and small shrubbery. Often a running stream with numerous swampy places, overgrown with brier tangles and alders, bounds the base of the hill as an additional attraction. It is seldom seen outside of its favorite woods and returns year after year to the same chosen haunts.
W. E. Clyde Todd (1940) says that in western Pennsylvania “wooded slopes are its chosen abodes, the shadier and cooler the better. * * * Deep ravines, down which trickle little streams, and the slopes of which support good stands of deciduous trees, with plenty of shrubbery and bushes for cover, are favorite resorts.” In Ritchie County, W. Va., William Brewster (1875) found it “most partial to the retired thickets in the woods along water courses, and seldom or never found in the high open groves.”
Spring.—The northward movement of the worm-eating warbler evidently begins in March, as the earliest arrivals from the Bahamas, the West Indies, and Cuba reach southern Florida during the first week in April. From its main winter resorts in Central America the flight seems to be partially across the Gulf of Mexico. Professor Cooke (1904) says in part: “The time of arrival on the coasts of Louisiana and Texas is about the same as in southern Florida. * * * Houston is the southernmost point in Texas from which it has been recorded to date, and Alta Mira is the northernmost point of record in Mexico. Since the species is apparently not common west of Louisiana or north of Vera Cruz, it is probable that the principal line of migration is from Yucatan and the coast immediately west of Yucatan directly north to the northern coast of the Gulf of Mexico.” According to Williams (1945) the species is common on the coast of Texas in spring, and it probably migrates along the coast. Thence the migration proceeds northward through the Mississippi Valley and through the Atlantic Coast States east of the Alleghenies, the warblers reaching the more northern breeding grounds by the middle of May, where nesting activities begin as soon as mates have been selected.
Nesting.—Evidently Thomas H. Jackson, of West Chester, Pa., was the first to report the discovery of the nest of the worm-eating warbler; he published an account of it in the American Naturalist for December 1869, from which Baird, Brewer, and Ridgway (1874) quote as follows: “On the 6th of June, 1869, I found a nest of this species containing five eggs. It was placed in a hollow on the ground, much like the nests of the Oven-Bird (Seiurus aurocapillus), and was well hidden from sight by the dry leaves that lay thickly around. The nest was composed externally of dead leaves, mostly those of the beech, while the interior was prettily lined with the fine, thread-like stalks of the hair-moss (Polytrichium). * * * So close did the female sit that I captured her without difficulty by placing my hat over the nest.”
This nest was quite characteristic of the species. Mr. Burns writes to me: “The nest, well hidden under a drift of dead forest leaves, never varied in composition in over a hundred examples examined by me, in partly skeletonized leaves and the characteristic reddish-brown lining of the flower stem of the hair moss.” Every one of 50 nests found by Mr. Jackson was lined with these flower stems, and out of 34 nests reported by Dr. Samuel S. Dickey (1934) only one failed to contain this material, being lined with “black and gray horsehair.” Samuel B. Ladd (1887) says that “sometimes fine grass and horse-hair are used as part of the lining.” Dr. Chapman (1907) writes: “Nests taken by J. N. Clark at Saybrook, Connecticut (C. W. C.) are composed of decayed leaves and lined with stems of maple seeds.” And there are probably a few other exceptions to the rule.
Most observers agree that the worm-eating warbler prefers to nest on hillsides, either sloping or steep, but a number of nests have been found on the sides of deep, shady ravines, or on steep banks. Mr. Ladd (1887), however, states: “I have observed that these birds are not confined necessarily to hill-sides, as was heretofore supposed, as I have taken three sets on level ground and in rather open places, with little shade. The experience of Mr. Thomas H. Jackson of this place, who has taken ten nests this year, corroborates this fact.”
The nests are generally well concealed under a canopy of dead leaves, drifted by the wind and lodged against a maple, beech, dogwood, or ash sapling, or under hydrangea, laurel, or rhododendron bushes, or under some bunch of weeds or other obstruction. They are sometimes concealed under the roots of a tree or in a cavity in a bank where they are protected somewhat by fallen leaves.
Eggs.—The number of eggs laid by the worm-eating warbler varies from 3 to 6, but the set usually consists of 4 or 5. The eggs are ovate or short ovate, sometimes rather pointed, and only slightly glossy. The white ground color is speckled and spotted with shades of “russet,” “vinaceous russet,” and “auburn,” intermingled with “light brownish drab” and “light vinaceous-drab.” The markings, usually more thickly grouped at the large end, vary considerably, some eggs being boldly marked, while others are almost immaculate, or have just a few pale freckles of “light brownish drab” and “fawn.” The measurements of 50 eggs average 17.4 by 13.6 millimeters; the eggs showing the four extremes measure 20.8 by 14.5, and 15.5 by 12.7 millimeters (Harris).
Incubation.—Frank L. Burns (1905) writes:
Incubation does not always commence immediately after completion of set, particularly if the season be young. It is probable that the second night witnesses the beginning of that period and, as far as my experience goes, I believe it is performed by the female alone. The male feeds her when covering newly hatched young.
The home-coming of a brooding bird, after a brief airing and feeding, is heralded several hundred yards distant by frequent chips and short flights from branch to branch near the ground, in leisurely fashion and circuitous route, until at length, arriving above the nest, she runs down a sapling and is silent. The bird