Ruby-crowned Kinglet

Regulus calendula

One of North America's smallest birds, the Ruby-crowned Kinglet can be recognized by its constant wing-flicking. The male shows its red crown only infrequently.

Interesting Information

  • The Ruby-crowned Kinglet is a tiny bird that lays a very large clutch of eggs. Although the eggs themselves weigh only 0.65 g (0.02 oz), an entire clutch can weigh as much as the female herself.

  • The Ruby-crowned Kinglet was described in 1766 by Linnaeus; its generic name is Latin for 'little king'.

  • It differs sufficiently in its voice and plumage from other kinglets that it is occasionally afforded its own genus, Corthylio.

  • They feed lower in the canopy than the Golden-crowned and characteristically hovers above a twig looking for caterpillars, aphids, and other insects.

  • A group of kinglets has many collective nouns, including a "castle", "court", "princedom", and "dynasty" of kinglets.


Adult Description

  • Tiny bird.

  • Dull, olive-green.

  • Wingbars.

  • Eyering.

  • Short tail.

  • In constant motion, continually flicking its wings.

  • Length Range: 11 cm (4.25 in)

  • Weight: 6 g (0.2 oz)

  • Size: Very Small (3 - 5 in)

Sex Differences

Sexes Similar

Male with red crown (usually hidden)


Immature similar to adult.


Photo taken from: The Sibley Field Guide by David Allen Sibley

© 2003 Cornell Lab of Ornithology


Preferred habitats include coniferous and deciduous forests.


Gleans food from tips of branches and bark. Hovers and gleans from foliage.


Small insects and their eggs.



Kingdom: Animalia
Phylum: Chordata
     Subphylum: Vertebrata
Class: Aves
Order: Passeriformes
Family: Regulidae
Genus: Regulus
Species: Regulus calendula
    Subspecies: Regulus calendula calendula
  Regulus calendula cineraceus
  Regulus calendula grinnelli
  Regulus calendula obscurus

Similar Species

  • Golden-crowned Kinglet has a white stripe above the eye, orange crown patch (male), and paler underparts.

  • Hutton's Vireo is larger, stockier, and has a stouter bill.

Bird Sound

Song a jumble of notes, starting with two or three high "tsees," followed by five or six lower "tur" notes, and ending with repeated "tee-da-lett" phrases. Call a quick "di-dit."

Eggs look like this

Photo taken from: ARCTOS Collaborative Collection Management Solution