The Inca Dove has been expanding its range in Texas since it was first collected at Laredo in 1866 (Butcher 1868). It next appeared at Austin in 1889 and by the early 1900s was breeding at San Antonio, New Braunfels, Austin and Waco. During the l950s sightings were made in Oklahoma and even as far north as Kansas (Oberholser 1974). Inca Doves occur primarily around human habitations, an association presumably brought about by the availability of water wherever people are found. Range expansion may be due to the creation of new habitat as humans settle previously unoccupied areas, as well as the ability of Incas to survive the cold of northern regions by nocturnal hypothermia and pyramid roosting to conserve heat (Robertson and Schnapf 1987, Mueller 1992).
Inca Doves feed on the ground in open areas such as barnyards, city parks, gardens, play grounds and lawns, or on elevated platform bird feeders. In dry soil they often whisk the bill from side-to-side to uncover seeds. Incas forage singly, in pairs, or as family groups during the breeding season, but larger flocks may form during the autumn and winter (Bent 1932, Johnston 1960). At Galveston, flocks containing up to 55 individuals formed during late spring and summer afternoons as birds arrived to forage in fields located as far as 0.5 to 0.8 km (0.3-0.5 mi) from their breeding sites (Quay 1987).
Inca Doves spend much of their time resting and they are often seen sunning or preening. The density of birds in urban areas may vary from as many as 10 birds per ha (2.47 acres) during the spring in Tempe, Arizona, to as few as 0.47 to 1.14 birds per ha during the winter at Galveston (Quay 1987, Mueller 1992).
DISTRIBUTION: The Inca Dove is a resident throughout most of Texas. Its scattered occurrence in the Trans-Pecos, Panhandle and north-central Texas may be the result of a smaller number of observers in these areas or from fewer rural dwellings or communities that offer suitable habitat. Inca Doves occur from near sea level to about 1650 m (5000 ft; Oberholser 1974)
SEASONAL OCCURRENCE: The Inca Dove is a permanent resident and there is no evidence of migration. Courtship and nest-building generally begin in late February. The TBBA data document a nest with young as early as March 21 in latilong 29097, Quad A3 and a nest with eggs as late as September 1 in latilong 28096, quad C7. Oberholser (1974) records eggs as early as March 12 and as late as October 30 with young in the nest as late as December 26. Since young have fledged in southern Texas during December and January (Johnston 1960), it would seem that, somewhere in Texas, Inca Doves are breeding every month of the year. Two or 3 and occasionally 4 or 5 broods may be produced per year (Harrison 1978).
BREEDING HABIT: Incas generally build their nests near human habitations. The male typically brings nesting materials to the female who then arranges them in the proper fashion. The nest is usually completed in about three days but is then abandoned and another nest begun. One or two “false” nests are constructed before the final nest is made (Johnston 1960). The nest is a compact platform of twigs, stems, grasses, leaves and strips of bark. The shallow cup is usually bare but may be sparsely lined with grass, Spanish moss, or feathers. Two glossy white eggs are laid following completion of the nest (Oberholser 1974, Harrison 1978). Incas occasionally repair or use as support the old nests of Northern Mockingbirds (Mimus polyglottos), Mourning Doves (Zenaida macroura), Cactus Wrens (Camplylo- rhynchus brunneicapillus), Northern Cardinals (Cardinals cardinals), and White-throated Towhees (Pipilo albicollis; Simmons 1925, Mueller 1992).
Nests are placed from 2 to 6 m (6-20 ft) above the ground. Plants used for nest support include conifers, cedar elm, winged elm, live oak, hackberry, sycamore, prickly ash, palms, vines and cacti. Nests have also been found on beams of open buildings, the top of a utility pole, and in a hanging basket (Simmons 1925, Oberholser 1974, Harrison 1978). In one unusual situation a nest was built on the intersection of guy wires with the trolley wire on a Street in Austin. Every 15 minutes as the cars passed the wires supporting the nest were raised at least 0.7 m (2 ft). In spite of this recurring disturbance two young were successfully fledged (Bedichek 1947). The nests of Inca Doves become reinforced with dried excrement from the nestlings and may be used year after year, in one case for 11 broods over four successive years (Johnston 1960). Both sexes incubate the eggs for 13-14 days. The young are brooded for 7-9 days and leave the nest 14-16 days after hatching (Johnston 1960, Harrison 1978).
STATUS: Changes in the breeding distribution of the Inca Dove in Texas since the publication of Oberholser’s account in 1974 include confirmation of its breeding status in far west Texas, at Amarillo in the Panhandle (latilong 35101, quad B7) and on the Texas-Oklahoma border, as well as several locations in eastern Texas and along the upper Texas coast. Data from 91 North American Breeding Bird Survey routes in Texas on which Inca Doves were detected suggest a small annual increase for the period 1980-2005 (Sauer et al. 2005).
Text by Stan D Casto (Posted with an update 2007)
Literature cited.
Bedichek, R.. 1947. Adventures with a Texas naturalist. Doubleday & Co., Garden City, NY.Bent, A. C. 1932. Life histories of North American gallinaceous birds. U. S. Natl. Mus. Bull., 162.
Butcher, H. B. 1868. List of birds collected at Laredo, Texas, in 1866 and 1867. Proc. Acad. Nat. Sci~ Philadelphia 20: 148-150.
Harrison, C. 1978. A field guide to the nests, eggs and nestlings of North American birds. Win. Collins Sons, Glasgow, UK..
Johnston, R. F. 1960. Behavior of the Inca Dove. Condor 62: 7-24.Mueller, A. J. 1992. Inca Dove (Columbina inca). In The birds of North America, No. 28 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
Oberholser, H. C. 1974. The bird life of Texas. University of Texas Press, Austin.
Quay, W. B. 1982. Seasonal calling, foraging, and flocking of Inca Doves at Galveston, Texas. Condor 84: 321-326.
Robertson, P. B. and A. F. Schnapf, 1987. Pyramiding behavior in the Inca Dove: Adaptive aspects of day-night differences. Condor 89: 185-187.
Sauer, J. R., J. E. Hines, and J. Fallon. 2005. The North American Breeding Bird Survey, results and analysis 1966-2005. Version 6.2 2006. USGS Patuxent Wildlife Research Center, Laurel MD < http://www.mbr-pwrc.usgs.gov/bbs>
Simmons, C. F. 1925. Birds of the Austin region. University of Texas Press, Austin.