Golden-cheeked Warbler

The bird weighs about 10 grams (0.34 ounces) and is about 12 centimeters (4.7 inches) long.

Adult males have yellow cheeks outlined in black, with a thin black line through each eye and extending backward. The upper breast, throat and back are black, while the lower breast and belly are white with some lateral black spotting or streaking. The wings are blackish with two white wingbars and tail feathers are black with the exception of the outermost tail feather on each side, which is white with a black shaft line.

Adult females are similar to adult males, but less strikingly marked. For example, the cheeks and center of the throat of females are yellowish, grading to pale buff or white on the abdomen. Additionally, the back is dark olive-green with thin black streaks. The sides of the throat are black with feathers tipped in white and the flanks, or sides, are covered with black streaks.

The golden-cheeked warbler makes sharp chipping calls while foraging for food. The male warbler emits a buzzy, hurried “tweah-tweah-twee-sy” call when defending its territory. Single, sharp chipping calls can frequently be heard from both male and female golden-cheeked warblers.

This small, insectivorous, migratory bird nests and breeds only in the mixed Ashe juniper/deciduous woodlands of central Texas. It uses the shredding bark of Ashe juniper trees as nest materials. While within its wintering range, the golden-cheeked warbler prefers foraging in deciduous trees in pine-oak forests.

Food foraging plays a role in site selection in breeding habitats. The golden-cheeked warbler is strictly insectivorous and typically feeds in the upper two-thirds of the canopy. It feeds on insects based on availability and difficulty of capture. Common invertebrates that the golden-cheeked warbler has been observed feeding on include spiders, brown and green caterpillars, green lacewings, small green cicadas, katydids, walkingsticks, deer flies, crane flies, adult flies, adult moths, small butterflies and other unidentifiable small insects.

On its wintering grounds, the golden-cheeked warbler is associated with mixed species flocks, typically consisting of other warbler species. These mixed species flocks may contain single golden-cheeked warblers per flock; however, as many as 12 have been observed together in a single flock.

The golden-cheeked warbler generally arrives at its Central Texas breeding grounds from January to March. The bird typically leaves its breeding grounds in late summer to begin its migration south, and is found in its wintering grounds from September to February.

Reproductive success of the golden-cheeked warbler is higher in large, unfragmented patches of habitat compared to small, fragmented patches and reproductive success increases as forest edge decreases.

The female golden-cheeked warbler does most of the work of nest building and incubating the eggs. They often nest in different trees each season, although nesting in the same tree for two or more years in succession has been noted. The selection of nesting habitat is especially important because nest location often affects reproductive success.

Females usually lay clutches of 3 or 4 eggs each year during the nesting season, and both adults tend to the offspring. Nesting warblers generally nest once each season unless the first nesting attempt fails, in which case they may attempt a second time.