In May, 1911, while I was waiting in Seattle, Wash., to take ship to the Aleutian Islands with R. H. Beck and Dr. Alexander Wetmore, we were shown by Samuel F. Rathbun the haunts of the lutescent orange-crowned warbler around Seattle. He says that it is one of the more common warblers of the region and is widely distributed. It favors small deciduous growths in more or less open situations, with or without accompanying evergreens. “It is also partial to the edges of old clearings fringed with a deciduous growth.” He says that it is an early migrant, arriving early in April or sometimes in the latter part of March, and departing in September.
On Mount Rainier, according to Taylor and Shaw (1927), it was—
fairly common in the Hudsonian Zone (4,500 feet to 6,500 feet); occurs also, but more rarely, in the Canadian Zone between 3,500 and 4,500 feet. * * * The lutescent warbler was commonly found in the mountain ash, huckleberry, azalea, and willow brush, principally in the open meadow country of the subalpine parks. Warm and sunny south-facing slopes were favorite places of resort, especially after a period of cold or fog. Occasionally the bird was found in patches of Sitka valerian; at other times in the lower branches of alpine firs. His summer foraging seems for the most part to be done within 10 feet of the ground, though in the fall, when migrating, he apparently takes to the tree tops.
Nesting.—On May 7, 1911, Samuel F. Rathbun took us over to Mercer Island in Lake Washington. At that time, this interesting island was heavily forested in some places with a virgin growth of tall firs, in which we saw the sooty grouse and heard it hooting, later finding its nest in an open clearing. While walking through another open space among some scattered groups of small fir trees, Mr. Beck flushed a lutescent warbler from her nest in a hummock covered with the tangled fronds of dead brakes (Pteridium aquilinum). The nest was so well concealed in the mass of dead ferns that we had difficulty in finding it. It was made of dead grasses and leaves, deeply imbedded in the moss of the hummock, and was lined with finer grasses and hairs. It held four fresh eggs. Three days later, Dr. Wetmore took a set of five fresh eggs at Redmond. This nest was located beside a woodland path at the edge of a swamp; it was well hidden on the ground, under a stick that was leaning against a log. It was made of similar materials and was lined with white horsehair.
Mr. Rathbun mentions three nests (MS.), found in that same vicinity; one was well hidden under some fallen dead brakes; and the other two were beautifully concealed in the centers of small huckleberry bushes.
William L. Finley (1904b) records six Oregon nests. The first “was tucked up under some dry ferns in the bank of a little hollow where a tree had been uprooted. * * * The second nest was on a hillside under a fir tree, placed on the ground in a tangle of grass and briar.” Another was “in a sloping bank just beside a woodland path. A fourth nest was tucked under the overhanging grasses and leaves in an old railroad cut.” He found two nests in bushes above ground. He saw a female carrying “food into the thick foliage of an arrow-wood bush. A cluster of twigs often sprouts out near the upper end of the branch and here, in the fall, the leaves collect in a thick bunch. In one of these bunches, 3 feet from the ground, the warbler had tunneled out the dry leaves and snugly fitted in her nest making a dark and well-protected home.” He found another nest 2 feet up in a bush, within a few yards of the ocean beach.
Henry W. Carriger, of Sonoma, Calif., (1899) mentions two more elevated nests of the lutescent warbler. He writes:
On May 31, 1897, I found a nest of the Lutescent Warbler placed three feet from the ground in a bunch of vines. * * * On May 3, 1899, * * * I flushed a bird from a nest in an oak tree, and was surprised to see it was a Lutescent Warbler. The nest was six feet from the ground and three feet from the trunk of the tree. A horizontal limb branched out from the tree and a small branch stuck up from it for about eight inches, and over this was a great quantity of Spanish moss (Ramalina retiformis), which fell over the horizontal limb. The nest is quite bulky, composed of leaves, grass and bark strips, lined with hair and fine grass, and was partially supported by both limbs and the moss, which is all about it and which forms quite a cover for the eggs.
Eggs.—The lutescent warbler lays from 3 to 6 eggs to a set, probably most often 4. These are ovate or short ovate and are practically lusterless. The white or creamy white ground color is speckled, spotted or occasionally blotched with shades of reddish brown, such as “russet,” “Mars brown,” “chestnut,” and “auburn,” intermingled with underlying shades of “light brownish drab.” The markings are usually concentrated at the large end, but some eggs are speckled more or less evenly over the entire surface. Small scrawls of blackish brown may be found on some of the more heavily marked types. The measurements of 50 eggs average 16.2 by 12.6 millimeters: the eggs showing the four extremes measure 17.7 by 12.8, 16.8 by 13.5, 14.7 by 12.2, and 15.9 by 11.1 millimeters (Harris).
Young.—We seem to have no information on incubation or on the care and development of the young.