Passerellidae

Passerellidae is a family of passerine birds known as the New World sparrows. They are distributed across the Americas from Alaska and Canada to southern South America, with greatest species richness in Central and North America. They occupy a wide range of habitats, including grasslands, shrublands, forests, and urban areas.

They are small to medium-sized birds with short, stout bills adapted for granivory; many also take insects, especially during breeding. Plumage tends to be cryptic browns, grays, and rufous, often with streaked undersides. They are generally ground foragers, scratching leaf litter or grass for seeds and invertebrates.

Systematics: The Passerellidae was established as a distinct family to recognize the New World sparrows as a separate lineage from Old World buntings and other Emberizidae. Molecular studies in the late 20th and early 21st centuries prompted the redefinition. The name derives from the genus Passerella, one of the older lineages in the group.

Species and ecology: The group includes numerous species across many habitats, from grassland scrub to montane forest. Nests are usually cup-shaped, built in shrubs or grasses, and clutches commonly contain three to five eggs. Both parents incubate and feed the young; many species migrate seasonally, while others are year-round residents.

Conservation: Most Passerellidae species are of least concern, but habitat loss, climate change, and introduced predators threaten a few. Ongoing habitat protection and careful management of agricultural lands help sustain populations.