Varied Bunting

Published by the Smithsonian Institution between the 1920s and the 1950s, the Bent life history series of monographs provide an often colorful description of the birds of North America. Arthur Cleveland Bent was the lead author for the series. The Bent series is a great resource and often includes quotes from early American Ornithologists, including Audubon, Townsend, Wilson, Sutton and many others.

Bent Life History for the Varied Bunting – the common name and sub-species reflect the nomenclature in use at the time the description was written.

The varied bunting is primarily a Mexican species, but three subspecies occur within the borders of the area covered by the A.O.U. Check-List. One race (P. v. pulckra) is resident in southern Baja California, another race (P. v. diekeyae) is a very rare summer resident in central and southern Arizona, and the nominate form is a summer resident in southwestern Texas, from west of the Big Bend country inland along the Rio Grande, eastward to the Gulf where it occasionally winters. Still another extralimital race (P. v. purpuraseens) is resident m Guatemala. These races are very similar and only can be separated by a comparison of museum specimens. Their habitats, behavior, and life history, while still not well known, are probably so much alike that most details concerning one race will undoubtedly apply to the others.

This is a bird of the desert and semiarid brush country of low and medium elevations; it is never found in heavily wooded areas. James C. Merrill (1879), referring to the Brownsville, Tex., region, Bays, “This beautiful species seems to be rather abundant in this vicinity, frequenting the mesquite-chaparral.” Phillips and Thornton (1949) reported it as a bird of the mesquite-salt cedar association in Presidio County, Tex. Thornton (1951) found it in the mesquite-creosote bush association, and Pulich (1963) observed birds in the Chisos Mountains in a “fairly dense stand of vegetation, together with a few cottonwoods (Populus sp.)” and again in the Big Bend National Park in “typical seepwillow (Baceharis glutinosa)-salt cedar (Tamarix galtica) -mesquite (Prosopis juliflora and Sophora .secundiflora) habitat, along with a few cottonwoods,” and “in a typical mesquitecatclaw (Acacia g’reggii) wash with scattered allthorn (Koeberlina spinosa) and sumac (Rhus sp.), bordered with creosote bush (Larrea trideiitata).” Land (1962), writing of birds found in the arid Motagua valley of Guatemala, says, “Recorded in July and September in scrubby woodland. Males were. singing on territory in July.”

Many years ago the varied bunting was reported as being abundant in the Brownsville region. Griscom and Crosby (1926), reporting on the birds of that region in the early 1920’s, listed it as a fairly common summer resident; however, at present it seems to be rare in that area, probably because much of the original brushy habitat association of this species has now been converted to farm land. In recent years most reports of this bunting have been from the semidesert areas of Brewster, Presidio, Terrell, and Crockett counties of western Texas.

Nesting: Van Tyne and Sutton (1937) reported that on May 29 a nest ready for eggs was found in a dense tangle along Maravillas Creek near Marathon, Tex. Allan R. Phillips wrote Wendell Taber that he found a “nest on 1 August 1954 about 3 feet up in the dead lower twigs of a ‘bachata’ bush (Condalia lycoides) on the northwest side, near Huasabas, Sonora. The nest was constructed of coarse old grayish grass-like blades (bark or weeds) bound with cobwebs? to two distinct but nearly vertical twigs, and, unsupported from below, was well lined with fine brownish-huffy grasses, the lining projecting above the top of the nest. The nesting tree and others of the same kind up to 10 or 12 feet in height provided good shade. There were two pinfeathered young several days old. The female came from the northeast side three times to feed the young, the male finally came with food and departed with a fecal sac. In approaching, both parents came in low through the bushes.”

Baird, Brewer, and Ridgway (1905) state that among the memoranda of Mr. Xantus, made at Cape St. Lucas, they found the following in connection with this species: “nest and three eggs *** obtained May 5 on a myrtle hanging down from very high perpendicular bluffs, nest and eggs of same found on vine ten feet high.” The nest is normally placed in a thick bush, low tree, or tangled vine. The records of eight sets of eggs collected in Cameron County, Tex., indicate that each nest was in a small bush; the lowest was only 16 inches from the ground and the highest was 5 feet. The nest is cup-shaped, compactly built, but somewhat untidy in appearance. rrhe materials used in its construction consist primarily of dry grass and small stems but may include strips of vegetable fiber, plant cotton, and other similar substances. One nest included a piece of cast-off snake skin, another a strip of paper. The nest is usually lined with rootlets and fine grasses, however five of the eight available records show that some hair was used in the lining.

Eggs: The varied bunting normally lays three or four eggs to a set. The shape varies from short-ovate to elongated-ovate. The shell is pale bluish white, unmarked, and the eggs are practically indistinguish able from those of the indigo and lazuli buntings. Measurements of 21 eggs average 17.8 by 14.3 millimeters, the eggs showing the four extremes measure 20.0 by 14.4, 19.0 by 15.0, and 16.5 by 13.5 millimeters.

Plumage: After the young leave the nest in juvenal plumage, the male passes through four different changes before he reaches the adult phase in the third winter, when he is over 2 years old. The female remains nearly the same after the post-juvenal molt with only slight changes from winter to summer. The juvenal plumage, both male and female, is similar to the first winter plumage of the female, but duller and more huffy brown, and the abdomen is huffy or grayish. This is described by Ridgway (1901) as follows: “above grayish brown or drab (less olivaceous than in summer female), the edges of retrices and primaries dull glaucous, or inclined to that color, middle and greater wing-coverts tipped with pale brownish buff, forming two indistinct narrow bands; under parts dull whitish medially, pale brownish laterally and across chest.”

After the juvenal stage, a first winter plumage is acquired by a partial post-juvenal molt. The male in this plumage is similar to the summer female except that he is more deeply colored and browner, both above and below, with only the center of the abdomen whitish. The female is quite similar in color but the upper parts are slightly darker and more brownish. The first nuptial plumage of the male, acquired by partial prenuptial molt, is much like that of the adult female. Van Tyne and Sutton (1937) refer to a specimen taken on May 29 and state, “A male bird taken by Semple * * * is in the first nuptial plumage, scarcely distinguishable from that of the female.” The first nuptial plumage of the female is much like that of the adult female but slightly more buffy. The male in second winter plumage, acquired by complete postnuptial molt, is similar to the adult male in winter, except that the wing bars are more buffy or brownish and the posterior lower parts are duller and more grayish. The second winter plumage of the female is like that of the adult female. The second nuptial plumage of the male, acquired by wear, is much like the nuptial plumage of the adult male except that the under parts are duller and more grayish or buffy brown. The third winter plumage of the male, the adult plumage, acquired by a complete postnuptial molt, is like that of the adult, however the feather tips and edgings tend to obscure the bright colors. These gradually become more apparent as the gray-brown edges wear away until they have practically disappeared by the beginning of the spring breeding season.

Food: Very little information is available concerning the food of this bunting; presumably, it is similar to that of the indigo and lazuli buntings. Pulich (1963) states, “an adult male and juvenile Were observed feeding upon weed-seeds *

Voice: James C. Merrill (1879) wrote concerning this species, “Its song has some resemblance to that of the Indigo-bird, and is constantly uttered.” George N. Lawrence (1874) wrote, “This beautiful little finch is quite a common species about the vicinity of Mazatlan, where it is a constant resident * * ~. It has a sweet little song, which it often warbles in the morning and evening from the top of some bush or weed in hearing of its modestly attired mate.” Herbert Brandt (1940) states of the male: “this gorgeously bedecked creature, in order to spread over the countryside its crisp, warbling whistle, invariably chooses a high, prominent perch, and although very busily engaged in song, it is ever alert, and too wary to allow a person’s very close approach.” Allan R. Phillips writes Taber: “the usual call is very sharp and strongly reminiscent of Oporornis tolmeiei * * ‘2’ Roger Tory Peterson (1960) describes the song as “a thin bright finch song, more distinctly phrased and less warbled than the painted bunting’s notes; notes not so distinctly paired as in song of lazuli bunting.”

Field marks: The adult male varied bunting cannot be confused with any other bird; he has a dark purplish-plum body that looks almost black at a distance, and a bright red nape, with blue crown and lighter blue rump. The most distinctive character is the red nape and dark body. Females and young males are plain grayish brown, and very similar to those of the indigo and lazuli buntings.

Behavior: Little is known concerning the behavior of the varied bunting; usually it is a retiring species, somewhat shy and secretive, and stays away from human habitations, remaining closely to the cover of its haunts in the semidesert brush. Consequently, the female is seldom observed. However, during the nesting season, the male selects some prominent perch in the vicinity of the nest from which he announces the occupation of his territory and utters his rather sweet song. Phillips notes that both parents assist in feeding the young.

Enemies: Apparently the varied bunting is not an infrequent host of the cowbird in some localities. Herbert Friedmann (1963) states, “RD. Camp collected a set of 2 eggs of this bunting with 1 of the cowbird in Cameron County, Texas, on June 4, 1927 * * There is another set of four eggs and one of the dwarf cowbird in the collection of the Oregon State College, taken by R. D. Camp on the same date. Of the 13 available records of the varied bunting nesting in Cameron County, two: slightly over 15 percent: include cowbird eggs. Such a small number, however, may not be representative.

Other races: The western race, Passerina versicolor pulchra Ridgway, is resident in southern Baja California north to Comondu; in winter, rarely to southern Sonora and Sinaloa. Ridgway (1887a) described this race as similar to the eastern race but “rather smaller, or with shorter wing and tail; adult male with red on occiput brighter, purple of throat less reddish (never decidedly red), flanks brighter plum-purple, and rump more purplish-blue or lavender * * William Brewster (1902) states that the females of this race differ considerably by being decidedly grayer, especially on the under parts and on the sides of the head and neck.

The intermediate race, Passerina versicolor diclceyae van Rossem, was described in 1934 and has been accepted by the A.O.U. Committee. This race is a rare local summer resident in southern Arizona (Baboquivarae and Santa Catalina mountains) and breeds south through central and eastern Sonora, southwestern Chihuahua south along the Pacific slopes to Colima. It winters from southern Sonora and southern Chihuahua south to Colima and Nayarit. Van Rossem (1934b) describes this race as “Similar in size to Passenna verswolor pulchra IRidgway, of southern Lower California. Females and young males prevailingly rufescent brown instead of grayish brown (as in versicolor) or brownish gray (as in pukhra). Adult males very similar to adult males of pulchra, and distinguishable only in series by the greater extent and brighter hue of the red nuchal patch.”

The third race, Passerina versicolor purpurascens Griscom, has been described from the arid Motagua valley of Guatemala. These birds are generally similar to those of southern Texas and northeastern Mexico, but they are much smaller, and darker and duller in overall coloration.

DISTRIBUTION
Range: Western and southern Texas to Guerrero and Oaxaca.

Breeding range: The eastern varied bunting breeds from western and southern Texas (Maria, Brownsville) south through central and eastern Mexico to Guerrero (Mexcala) and Gaxaca (Mitla).

Wintering range: Winters from southern Sonora (Chinobampo), central Nuevo Le6n (Monterrey), and southern Texas (lower Rio Grande Valley) south to Guerrero and Oaxaca.

Casual records: Casually north in spring and summer in Texas to Edwards County and Aransas Refuge.

Migration: Early dates of spring arrival are: Nuevo Le6n: China, April 17. Texas: Brownsville, April .6; Chisos Mountains, April 29. New Mexico: Guadalupe Canyon, June 9. Arizona: Tucson, May 4.

Late dates of fall departure are: Arizona: Mohave Mountains, October 27. Texas: Corpus Christi, October 27; Cameron County, September 6.

Egg dates: Baja California: 3 records, May 5 to May 12. Texas: 14 records, April 3 to July 8; 8 records, April 26 to July 7.