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Ruby-crowned Kinglet - BirdForum Opus

(Redirected from Corthylio calendula)
Photo © by fugl.
Reno, Nevada, USA
Corthylio calendula

Regulus calendula


9-11cm. (3-4 inches) A tiny bird with a thin bill, broken eye ring, olive upperparts, pale olive underparts. It has a single major white wing bar with a very minor secondary bar, often indistinct or hidden. Flight feathers and tail have yellow edges. The male has a thin red patch in centre of crown that can be raised (often inobvious or hidden). The most significant diagnostics for identification are the single wing bar, the size, and the frenetic level of activity.


Showing yellow soles
Photo © by KC Foggin
Myrtle Beach, South Carolina, March 2014

Most of North America


Photo © by KC Foggin
Myrtle Beach, South Carolina, USA, February 2021

This is a polytypic species[1] consisting of 3 subspecies



Comon and widespread in coniferous and mixed forests, as well as riparian areas. Highly migratory.


Often travels in small mixed flocks. Forages busily (almost frantically) along branches of trees and bushes. Often in dense brush or thickets. Extremely active, rarely perching for more than a few seconds. Only raises the brilliant ruby crest when excited.

  • Diet: The diet includes insects such as moths, beetles, ants, wasps, butterflies, caterpillars, spiders and elderberries and weed seeds. They also drink tree sap and some fruit.
  • Breeding: Both sexes build the nest which is a hanging globe shaped cup among twigs of a pine branch. The nest is built of moss and cobwebs and lined with feathers, rootlets and soft bark. The nest can be found in a spruce, firs or pines. 5-11 (usually 7-9) eggs are laid which are white with brown spots. The eggs hatch within 12-13 days and are incubated by the female. The first young leaves the nest approximately 13 days after hatching.


  1. Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, J. A. Gerbracht, D. Lepage, B. L. Sullivan, and C. L. Wood. 2021. The eBird/Clements checklist of Birds of the World: v2021. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/

Recommended Citation

External Links

GSearch checked for 2020 platform.1