The Cuban bee hummingbird, the smallest living bird, measures 5 cm and weighs 1.5-2 grams. It beats its wings 80 times per second and visits 1200-1500 flowers daily.

The Weebill, the smallest known Australian bird, inhabits woodlands with a short pale beak, light brown feathers, and yellowish underparts, creating dome-shaped nests for insects.

Austrian paradolates, small 8-12 cm, inhabit eucalypt forests, with short tails, stubby tails, black wings, white dots, and olive green coverings. They control lerps in Australian forests.

Golden headed Cisticola, found in India and Australia, are small, bright-colored birds with bright plumage during breeding season. They build nests using leaves, grasses, and spider webs.

Goldcrest, Ireland's smallest song bird, 9 cm long, named after bright yellow crown, is known for high-pitched contact calls in broadleaf forests and gardens.

Brown gerygone, a small passerine bird, grows 8-10 cm in Australia's coastal areas and rain forests, typically in small groups, primarily on treetops for insect capture.

American goldfinch is a small migratory bird found in Lowa, New Jersey and Washington, with bright yellow body and black forehead. Breeding occurs in North Carolina.

Bananaquits, small, colorful birds with 41 recognized subspecies, are found in Central and South America, clinging to flowers for nectar and building globe-shaped nests.

Tropical parulas, 11 cm long, found in South Mexico and Texas, have bluish upper and yellow underparts, 14 subspecies, and primarily feed on insects, spiders, and berries.

Crimson chats are endemic Australian birds, weighing 13 grams and 10-13 cm long. They walk and run, with bright red crowns and black markings. Females lay eggs.