Prothonotary Warbler

Protonotaria citrea has the bill long, stout, aculeate, the upper mandible nearly straight but somewhat decurved at the slightly notched tip, the ridge of culmen is pronounced and slightly parts the feathers of the forehead, the rictal bristles are barely evident. The wing is rather broad, not especially pointed, the tail is short, square, or even somewhat rounded, the outer feather being slightly the shortest; the under tail-coverts are long, reaching to within half an inch, or less, of the end of the tail; the hind-toe is shorter but stouter than the middle toe.

In color the sexes closely resemble each other, the male having the head brighter.

Distinguishing Characters

The prevailing orange-yellow color, grayish wings and absence of wing-bars will always distinguish this species.

Length (skin), 4.90; wing, 2.85; tail, 1.85; bill, .55. [inches]

♂ Adult Male, Spring.- Whole head orange-yellow; back yellowish green; rump and upper tail-coverts gray; tail margined with gray, all but the central pair of feathers white on the inner web except at the tip, which is black; wings black, externally margined with gray, lesser coverts like the back, greater coverts tinged with same, first primary covert blackish margined with whitish, bend of wing yellow; below orange-yellow changing to white on the crissum; bill black.

♂ Adult Male, Fall.- Similar to adult male in Spring, but hind-head always washed with dusky; bill brownish.

♂ Young Male, Fall.- Similar to adult male in Fall but white on inner webs of tail-feathers more restricted and more or less mottled with blackish; first primary covert grayer.

♀ Adult Female, Spring.- Resembles adult male, but crown duller, greenish yellow or orange, back the same changing to gray on the rump; tail with less white, the black areas duller; below averaging paler than the adult and with more white on the lower belly.

♀ Adult Female, Fall.- Resembles adult female in Spring.

♀ Young Female, Fall.- Resembles adult female in Fall.

Nestling.- Above dusky olive-green varying markedly to brown; below dusky grayish tinged with yellow or brown on the breast and sides, whiter on the belly.

The Bird and its Haunts

The charm of its haunts and the beauty of its plumage combine to render the Prothonotary Warbler among the most attractive members of this family. I clearly recall my own first meeting with it in the Suwanee River region of Florida. Quietly paddling my canoe along one of the many enchanting, and, I was then quite willing to believe, enchanted streams which flowed through the forests into the main river, this glowing bit of bird-life gleamed like a torch in the night. No neck-straining examination with opera-glass pointed to the tree-tops, was required to determine his identity, as, flitting from bush to bush along the river’s bank, his golden plumes were displayed as though for my special benefit.

If all our Warblers had received the attention which the Prothonotary’s attractions have won for him, the preparation of this volume would have been a much easier and more satisfactory task. Space, indeed, prohibits adequate quotations from the monographs of which this bird has been the subject, and for more detailed information than can here well be presented, the student is referred to the papers cited beyond. From the one by William Brewster, the following admirable pen picture of the Prothonotary and its haunts is extracted.

In the heavily timbered bottoms of the Wabash and White Rivers, Brewster writes, two things were found to be essential to the Prothonotary’s presence, “namely, an abundance of willows and the immediate proximity of water. Thickets of button bushes did indeed satisfy a few scattered and perhaps not over particular individuals and pairs, but away from water they never were seen. So marked was this preference, that the song of the male heard from the woods indicated to us as surely the proximity of some river, pond, or flooded swamp, as did the croaking of frogs or peeping of hylas.

In general activity and restlessness few birds equal the species under consideration. Not a nook or corner of his domain but is repeatedly visited through the day. Now he sings a few times from the top of some tall willow that leans out over the stream, sitting motionless among the yellowish foliage, fully aware, perhaps, of the protection afforded by its harmonizing tints. The next moment he descends to the cool shades beneath, where dark, coffee-colored water, the over-flow of pond or river, stretches back among the trees.

This Warbler usually seeks its food low down among thickets, moss-grown logs, or floating debris, and always about the water. Sometimes it ascends tree-trunks for a little way like the Black and White Creeper [=Warbler], winding about with the same peculiar motion. When seen among the upper branches, where it often goes to preen its feathers and sing in the warm sunshine, it almost invariably sits nearly motionless. Its flight is much like that of the WaterThrush (either species) and is remarkably swift, firm, and decided. When crossing a broad stream it is slightly undulating, though always direct.”

Of the Prothonotary farther south in the Mississippi Valley, Allison (MS.) writes:

“The typical haunt is low, flat, woodland, preferably with some standing water; this is usually a river bottom, though a ‘bay-gall,’ or low swamp among pine-lands, wooded with white bay, black-gum, etc., often answers the purpose. In Louisiana, a piece of ground recently deposited by the Mississippi River, and covered with a thick growth of willows, is attractive to this Warbler. It joins less than many other species with the roving bands of migrant Warblers in the upland woods.”

Song

“The usual song of the Prothonotary Warbler sounds at a distance like the call of the Solitary Sandpiper with a syllable or two added, a simple peet, tweet, tweet, tweet, given on the same key throughout. Often when the notes came from the farther shore of a river or pond we were completely deceived. On more than one occasion, when a good opportunity for comparison was offered by the actual presence of both birds at the same time, we found that at the distance of several hundred yards their notes were absolutely indistinguishable; nearer at hand, however, the resemblance is lost,
and a ringing penetrating quality becomes apparent in the Warbler’s song. It now sounds like peet, tsweet, tsweet, tsweet, or sometimes tweet, tr-sweet, tr-sweet, tr-sweet. When the bird sings within a few yards the sound is almost startling in its intensity, and the listener feels inclined to stop his ears. The male is a fitful singer, and is quite as apt to be heard in the hot noontide or on cloudy days, when other birds are silent, as during the cool morning and evening hours. The ordinary note of alarm or distress is a sharp one, so nearly like that of the Large-billed Water-Thrush (Seiurus motacilla) that the slight difference can only be detected by a critical ear. When the sexes meet a soft tchip of recognition common to nearly all the Warblers is used. In addition to the song above described the male has a different and far sweeter one, which is reserved for select occasions, an outpouring of the bird’s most tender feelings, intended for the ears of his mate alone, like the rare evening warble of the Oven-bird (Seiurus aurocapillus). It is apparently uttered only while on the wing. Although so low and feeble as to be inaudible many rods away, it is very sweet, resembling somewhat the song of the Canary given in an undertone, with trills or ‘water notes’ interspersed. The flight during its delivery is very different from that at all other times. The bird progresses slowly, with a trembling, fluttering motion, its head raised and tail expanded. This song was heard most frequently after incubation had begun.” (Brewster.)

Nesting Site

Brewster writes that to give an account of all the situations in which he has found nests of this species “would entail a description of nearly every conceivable kind of hole or cavity that can be found in tree-trunks. The typical nesting-site, however, was the deserted hole of the Downy Woodpecker or Carolina Chickadee. The height varied from two to fifteen feet, though the usual elevation was about four.” Barnes’s observations agree with Brewster’s but he adds that, rarely, nests are found as high as twenty-five feet. Both writers state that the height of the nest and its distance from the water depend upon the fall in the water after the site has been selected.

A wide, and apparently not infrequent departure from the type of nesting-site just described is the vicinity of houses (Ganiers) and, in one instance, a railroad bridge (Roberts) when, bluebird-like, the bird accepts nest-boxes or similar situations.

Nest

The nest is constructed by the female. The male accompanies her on her search for material and rarely brings a small bill full but leaves it “on the outside of the hole for her to carry in and arrange. The female begins by bringing some fine straws or grasses which are arranged in a nice nest in the bottom of the hole. Next she procures some fine strips of grape-vine bark, and lines her nest, and lastly covers this all over carefully and thickly with moss which grows on the bark of trees standing in the water. They very rarely use any feathers or hair, and sometimes build their nest entirely of one of the above materials.” (Barnes.)

Nests collected by Wayne in South Carolina were made of lichens and lined with cypress leaves (C. W. C.).

Ganier (MS.) writes that in Mississippi the birds “frequently excavate their own hole in the soft cottonwood stumps,” a habit not mentioned by other writers I have consulted.

Eggs

5 to 7, usually 6. Ground color a rich creamy white to buffy, very glossy and very heavily and profusely blotched and spotted with rich chestnut-red, many lavender and purplish shades occurring. The heaviest and richest marked of North American Warblers’ eggs; in shape a rounded oval tending to become nearly spherical, the larger end having the heavier markings. An extreme type has rich cream ground with a few scattering spots of purplish brown. Size; average, .70x.57; extremes, .76x.59, .65x.57, .70x.53, .72x.61.

Frank M. Chapman – The Warblers of North America (1917)