GOLDEN-CHEEKED WARBLER. The golden-cheeked warbler (Dendroica chrysoparia) is truly a "native of Texas." Its nesting range is restricted to Texas, and from early March until mid-July this beautiful warbler is found nowhere else in the world. It inhabits the wooded slopes and canyons of the Edwards Plateau and the adjacent area to the north in places typically covered with Ashe juniper, Juniperus ashei. Although this avian species formerly occupied forty-one of the 254 Texas counties, today its known nesting range covers only thirty-three. The golden-cheeked warbler ranges from the Austin area southwest along the Balcones Escarpment almost to San Antonio, and west across the Edwards Plateau to the western portion of the Nueces River drainage in Kinney County. From there its range extends northeast to about Junction in Kimble County, skips Mason County, and goes eastward to Llano County and northward to Palo Pinto County. The bird is not found in Brown, Comanche, or Mills County. On the east side of the Brazos River, the species is limited to small portions of Hood and Johnson counties. From its eastern boundary, the range extends southward from Somervell County through parts of Bosque, Coryell, Bell, and Williamson counties. Concho and Tom Green counties may have also once been a part of this warbler's range. Golden-cheeks migrate from Texas through the mountainous areas of the Sierra Madre Oriental of Mexico to Central America. There they spend the winter in the oak- and pine-covered mountains of central and eastern Guatemala, Honduras, and Nicaragua. In February they move northward to their nesting grounds on the Edwards Plateau, and except for two unexplained late fall migration records, one in Florida and the other on the Farallon Islands off the coast of northern California, they have never been recorded anywhere else in the United States but in Texas.
This species belongs to the parulid family, which are known as New World warblers. The golden-cheeks are sometimes called the butterflies of the bird world because of their vivid colors. The adult male has a jet black back, throat, neck, and upper breast and sides. The wings, except for two white bars, and the tail are principally black. The lower breast and belly are white. The cheeks and the line over the eyes and sides of the neck are golden yellow; hence the bird's name. Immature males resemble the females, their backs being predominantly olive green and their cheeks less conspicuously colored than those of the adult male. Females also have thin black streaks on their body. The golden-cheeked warbler's preference of habitat is so strongly developed that it inhabits only those Texas counties that contain mature Ashe junipers, though it avoids small patches of old juniper. Dense stands of Ashe juniper are locally known as cedar brakes, and golden-cheeks occupy upward of several hundred such areas. Other names for Ashe juniper are Mexican, mountain, or blueberry cedar; to many persons it is simply cedar. Only Ashe juniper meets the requirements of this rare bird. Somehow, in its evolutionary development, the female golden-cheek learned to construct nests of strips of mature Ashe juniper bark. Neither young Ashe juniper nor either of the other two species of juniper found in the warbler's range offers acceptable nesting material. Nor is suitable habitat provided by young, second-growth juniper stands or grassland brush recently invaded by juniper as a result of overgrazing. Although built of cedar bark, the warblers' nests are not placed only in Ashe junipers but have been found in a variety of other trees-Texas oak, cedar elm, Arizona walnut, and, on one occasion, bald cypress.
Golden-cheeks usually occur in small groups. Pair bonds are established when females arrive on the nesting grounds. Females do all the nest building and incubation of the three to four eggs. The nest is usually camouflaged to blend with the bark of the trees. Nests are commonly found at heights of fifteen feet, although they have been placed as low as five feet and as high as thirty-two feet. The male spends his time singing his distinct song and defending his territory. A territory study of approximately seventy acres in Kendall County showed that fourteen territories ranged in size from about three to six acres per pair of golden-cheeked warblers. The male assists the female in feeding and caring for the young. The young leave the nest in eight or nine days, and remain in the vicinity as a rather loose family group cared for by both parents. Birds of a particular locale return to the same area year after year. Female brown-headed cowbirds deposit their eggs in the golden-cheeks' nests, leaving the task of incubating and caring for the young to foster parents. After a little over a month the young cowbirds depart to join their own kind. Although such brood parasitism by cowbirds is known to be detrimental to some avian species, present knowledge indicates that the cowbird may not be a serious threat to the survival of the golden-cheeked warbler. That distinction belongs to man, though the bird has several other natural enemies including rat snakes. Loss of habitat due to land clearing and urbanization has made inroads in the golden-cheeked warbler population, and the bird has disappeared from areas that formerly were known to harbor it. This species probably never was abundant, and at most the present total population is between 9,644 and 32,032 birds, a mere handful compared to the numbers of many avian species. For these reasons the United States Fish and Wildlife Service designated it an endangered species in 1990. Careful monitoring and management must be maintained to preserve this unique Texas species for future generations. In 1993 the Balcones Canyonland Conservation Plan was being considered to provide land for the protection of forty animal species, including the golden-cheeked warbler. Objections by land owners caused Governor Ann Richards to reject the plan for a critical habitat designation in the fall of 1994.
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Uploaded on June 15, 2010. Published by the Texas State Historical Association.