- 3.9–4.3 in
- 7.1–8.3 in
- Paruline à flancs marron (French)
- Reinita de costillas castañas (Spanish)
- On the wintering grounds in Central America the Chestnut-sided Warbler joins in mixed-species foraging flocks with the resident antwrens and tropical warblers. An individual warbler will return to the same area in subsequent years, joining back up with the same foraging flock it associated with the year before.
- The Chestnut-sided Warbler sings two basic song types: one is accented at the end (the pleased-to-MEETCHA song), and the other is not. The accented songs are used primarily to attract a female and decrease in frequency once nesting is well under way. The unaccented songs are used mostly in territory defense and aggressive encounters with other males. Some males sing only unaccented songs, and they are less successful at securing mates than males that sing both songs.
- Breeds in early successional deciduous woods.
- Winters in moist tropical forest.
Insects and other arthropods, occasionally fruit.
- Clutch Size
- 3–5 eggs
- Egg Description
- Creamy white or greenish with brown speckles.
- Condition at Hatching
- Helpless with sparse down.
Nest an open cup woven of bark strips, weed stems, grasses, and plant down. Lined with fine grasses, hair or rootlets. Placed in small crotch of shrub or within a group of thin vertical stems, less than 2 m (6.5 ft) from ground.
Gleans insects from the bottom of leaves.
Populations increased in 19th century, slightly decreasing now.
- Dunn, J. L., and Garrett, K. L. 1997. A Field Guide to Warblers of North America. Houghton Mifflin Co., Boston.;
- Richardson, M., and D. W. Brauning. 1995. Chestnut-sided Warbler (Dendroica pensylvanica). In The Birds of North America, No. 190 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.