During the summer months Dendroica chrysoparia has a very narrow breeding range on the Edwards Plateau, Lampasas Cut-Plain, and Llano Uplift regions of central Texas. The bird migrates in the winter months to the highlands of Guatemala, Honduras, and Nicaragua.
The golden-cheeked warbler is an extreme habitat specialist that requires stands of mature Ashe juniper to build its nest. During the breeding season the birds inhabit woodlands containing a majority of Ashe juniper along with other trees such as Texas Oak, Scaley Bark Oak, and Plateau Live Oak. Dendroica chrysoparia spends winters in pine-oak forest.
The warbler was named for the distinctive plumage on its face. The golden-cheeked warbler is the only North American warbler with radiant yellow cheeks outlined in black. This characteristic is present on both the female and the male though they are sexually dimorphic. The male golden-cheeked warbler has a more distinctly marked plumage than the females. A thin black line goes through each dark brown eye and extends to the back of the head. The upper breast and throat are black, while the lower breast and belly are white with black streaks. The upper and lower mandibles, legs, and feet are black. The wings of Dendroica chrysoparia are blackish with two white wingbars.
Female D. chrysoparia looks similar to the males, but they have a less dazzling plumage. The back of the adult female is dark olive-green with thin black streaks. The cheeks are yellowish, but a duller shade than the males. The juveniles are similar in coloring to the females.
The female golden-cheeked warbler spends approximately 4 days in early April building a compact nest comprised of Ashe juniper bark strips bound with spider webs and grass. Females usually place their nests in the upper two-thirds of nest trees. Ashe juniper is the most common nest tree for the golden-cheeked warbler, but the nests can also be found in oaks, walnuts, pecans, and bald cypress. Females lay clutches of 3-4 creamy white eggs speckled with brown. Incubation is done by the female and lasts 12 days. During incubation D. chrysoparia spends at least 75% of daylight hours on the nest.
Golden-cheeked warbler hatchlings are fed by both the male and the female. Fledging occurs at about 9 days. The fledglings depend upon their parents for at least 4 weeks after leaving the nest.
The warbler migrates to its winter home between the period of July-October. The male golden-cheeked warblers arrive in their central Texas breeding grounds in early March about 5 days before young males and females. During this period, males mark territories and begin to exhibit themselves vocally by "chip" noises in preparation for the arrival of the females. These "chip" noises are used for more than just attracting females. Golden-cheeked warblers use single "chip" or "double-chip" notes as alarm calls.
The female is considered shy and seldom noticed except when intruders such as fox squirrels, opossums, and scrub jays disturb the nest. But the male warbler is by no means shy. He is often seen foraging and singing from sunup to sundown.
The golden-cheeked warbler is entirely insectivorous. Prey items include beetles, soft-bodied caterpillars, deer flies, and spiders. The warbler spends most of its time foraging on foot moving from branch to branch picking insects from the foliage. It forages in the upper two-thirds of its habitat.
The golden-cheeked warbler is a beautiful bird that could be enjoyed by bird watchers.
Implementing conservation steps for the golden-cheeked warbler will cost taxpayers money. Money will also be lost by preserving the land for the warbler instead of using it for homes and industries.
Dendroica chrysoparia was listed as endangered in May 1990. The population in 1974 was estimated at 15,000 individuals. In 1990 only an estimated 2,200 to 4,600 birds remained. The drastic decline in the golden-cheeked warbler is due primarily to loss of mature Ashe juniper habitat. The expansion of the cities of Austin, San Antonio, and Waco has had a serious impact.
To stop the decline of golden-cheeked warbler habitat, many conservation measures are being implemented. The Balcones Canyonlands Conservation Plan (BCCP) is a conservation plan that sets up preserves for the golden-cheeked warbler. Another habitat preservation step is the establishment of the Balcones Canyonlands National Wildlife Refuge. The refuge wants to add at least 41,000 acres onto its already 3,500 acre area for golden-cheeked warbler breeding habitat.
Another threat to the warbler is the brown-headed cowbird. The cowbird exhibits brood parasitism on the warbler by laying eggs in golden-cheeked warbler nests. The cowbird eggs hatch two days before the warblers giving them the advantage over the golden-cheeked warbler hatchlings. The cowbird young develop more rapidly than the golden-cheeked warbler young. This enables the cowbird to take more than an equal share of food brought to the nest.
The increase in cowbird populations is due to human conversion of forests into farms and pastures. Today the cowbird poses a major threat to the species it parasitizes.
Nichol Stout (author), University of Michigan-Ann Arbor.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
living in the southern part of the New World. In other words, Central and South America.
uses sound to communicate
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
uses sight to communicate
Bent, Arthur. 1963. Life Histories of North American Wood Warblers. Dover Publications, Inc. New York, N.Y.
Ehrlich, Paul, David Dobkin, Darryl Wheye. 1988. The Birder's Handbook.
Ehrlich, Paul, David Dobkin, Darryl Wheye. 1992. Birds in Jeopardy.
U.S. Fish and Wildlife Service. 1992. Golden-cheeked-warbler recovery plan. United States Fish and Wildlife Service. Austin, TX.