About Elaenia flavogaster (Thunberg, 1822)
The yellow-bellied elaenia (scientific name Elaenia flavogaster, first described by Thunberg in 1822) is 15 to 17 cm (5.9 to 6.7 in) long and weighs 21 to 29 g (0.74 to 1.0 oz). It is a medium-sized bird with a small head and a bushy crest. The sexes share identical plumage. Adults of the nominate subspecies E. f. flavogaster have a brownish olive crown, with a partially concealed white stripe running through the center of the crest. Their face is mostly pale brownish olive, with whitish lores and a faint whitish eyering. Their upperparts are brownish olive. Their wings are slightly darker than the back; flight feathers have yellowish white edges, and wing coverts have yellowish white tips that form two distinct wing bars. Their tail is also slightly darker than the back. Their throat is pale gray, their breast is olive gray, and their belly ranges from yellow to pale yellow to whitish. Compared to the nominate subspecies, E. f. subpagana has browner olive upperparts and yellower underparts; E. f. pallididorsalis is overall grayer, with slightly greener upperparts; E. f. semipagana is paler overall, with a grayer face, less white on the crest, a whiter throat, and a paler belly. For all subspecies, both sexes have a dark brown iris, a black bill with a paler base to the lower mandible, and black legs and feet. The four subspecies of yellow-bellied elaenia have the following distributions: E. f. subpagana ranges from southern Veracruz and the Yucatán Peninsula in southeastern Mexico, south through Belize, Guatemala, El Salvador, Honduras, and Nicaragua into Costa Rica. It is also found on Isla Mujeres off Quintana Roo, Mexico, and Coiba Island, Panama. E. f. pallididorsalis is found in Panama and adjacent islands, excluding Coiba. E. f. flavogaster occurs in the northern half of Colombia; most of Venezuela including Margarita and Patos islands; Trinidad; Tobago; St. Vincent, the Grenadines, and Grenada in the Lesser Antilles; the Guianas; most of Brazil excluding western and central Amazonas; southeastern Peru; the northern half of Bolivia; eastern Paraguay; and northeastern and northwestern Argentina. It also occurs as a vagrant in Uruguay. E. f. semipagana is found in extreme southwestern Colombia, Ecuador west of the Andes including Puná Island, Tumbes Department in extreme northwestern Peru, and intermittently along the east side of the Andes through Peru. The yellow-bellied elaenia lives in a wide variety of habitats, ranging from arid to humid. Almost all of its occupied habitats are at most lightly wooded; it avoids dense forest except along dense forest edges. Its known habitats include savanna, scrublands, semi-open woodlands, secondary forest, brushy areas along watercourses, clearings with scattered trees, tree-containing suburban parks, and gardens. The species reaches different maximum elevations across its range: 2,000 m (6,600 ft) in Mexico, 1,700 m (5,600 ft) in northern Central America, 2,200 m (7,200 ft) in Costa Rica, 2,400 m (7,900 ft) in Colombia, 1,300 m (4,300 ft) in Ecuador, 1,500 m (4,900 ft) in Peru, 1,750 m (5,700 ft) in Venezuela, and 1,500 m (4,900 ft) in Brazil.
