Home, near and far.
This species is found throughout North America, breeding in coniferous forests across Canada, Alaska, northern New England, and the western United States. They winter in the southern United States and Mexico.
Birds Heard
FIELD GUIDE
FIELD GUIDE
Kinglets
Ruby-crowned Kinglet
Corthylio calendula
The Ruby-crowned Kinglet is a very small, active songbird found across North America. It is known for its olive-green plumage, prominent white eye-ring, and a distinctive wing-flicking behavior. Males possess a brilliant ruby-red crown patch, though it is often concealed.
MigratoryTiny songbirdInsectivorousWing-flicking
- Length
- 9-11 cm
- Wingspan
- 16-18 cm
- Weight
- 5-10 g
Typical adult measurements.
Individuals and populations vary.
01 / The telltale details
You’ll know it
when you see it.
Start with shape and behavior. Then look for the smaller details.
- 01
Overall Plumage
Both sexes are olive-green to gray on their upperparts with dusky white underparts.
- 02
Wing Bars and Eye-ring
Features two strong white wing-bars, with the lower one often edged in black, and a prominent white eye-ring that may be broken or uneven.
- 03
Male Crown Patch
Males have a scarlet crown patch, typically hidden unless the bird is excited, agitated, or singing. Females lack this patch.
- 04
Behavior
Constantly flicks its wings as it moves quickly through foliage.
02 / A place in the world
Where life
takes it.
During the breeding season, Ruby-crowned Kinglets prefer coniferous forests, including spruce, fir, and Douglas-fir. In migration and winter, they can be found in a wider variety of habitats, such as deciduous woodlands, mixed forests, thickets, old fields, gardens, and parks.
Stay a while. Or follow the season.
Ruby-crowned Kinglets are mostly migratory, moving to lower latitudes or elevations for winter. Some western populations may be permanent residents. They migrate earlier in fall and later in spring than Golden-crowned Kinglets.
03 / Listen a little closer
A voice
of its own.
The song is surprisingly loud and complex for such a small bird, often described as a jumbled, three-part ramble with high-pitched notes, low trills, and a repeated three-note phrase. Calls include a dry "ji-dit."
04 / The life behind the feathers
A day in its world.
On the menu.
Their diet primarily consists of insects and other small invertebrates, such as wasps, ants, beetles, moths, spiders, and pseudoscorpions. They also consume some berries, seeds, and tree sap, especially in winter.
These birds forage actively and acrobatically in trees and shrubs, often at lower and middle levels. They may hover to capture aerial prey or pluck insects from foliage.
A place to begin.
The female builds a deep, hanging cup-shaped nest, often in a spruce tree, suspended from twigs below a horizontal branch and protected by foliage. Clutches typically contain 5-11 eggs, with up to 12 eggs, which is the largest clutch size for a North American passerine of its size.
The little routines.
Ruby-crowned Kinglets are restless and energetic, constantly flitting and hopping through foliage. They often associate with mixed flocks of other small insectivorous birds during migration and winter.
One more reason to pay attention
A familiar face.
A few surprises.
The Ruby-crowned Kinglet was moved to its own genus, Corthylio, in 2021 due to its distinct characteristics compared to other kinglets.
An entire clutch of Ruby-crowned Kinglet eggs can weigh as much as the female herself.
The oldest known Ruby-crowned Kinglet lived to be at least 8 years and 8 months old.
05 / An eye for the difference
Could it be
someone else?
Golden-crowned Kinglet
Regulus satrapaRuby-crowned Kinglets have a distinct white eye-ring, while Golden-crowned Kinglets have a prominent white eyebrow stripe and a black eye-line.
Hutton's Vireo
Vireo huttoniHutton's Vireos are slightly larger with a more conical bill and do not flick their wings as constantly as Ruby-crowned Kinglets.
Behind these field notesResearch & references · 12 sources
AI-assisted species research. Prepared September 2026. Details can vary across regions and populations.