When do juncos leave Colorado?

Dark-eyed Juncos never fully leave Colorado: numbers fall back below half their usual rate by early April, but some are still reported in every week, about 6.4% of checklists at the low.

When is the best time to see juncos in Colorado?

The Dark-eyed Junco is reported most often in the second week of December, on about 38% of Colorado checklists.

Dark-eyed Junco · Junco hyemalis

When Do Juncos Arrive in Colorado?

Photo: Jimmy Dee, CC BY-SA 4.0 via iNaturalist

Dark-eyed Juncos are in Colorado all year, but most are here in winter: numbers build from the second week of October, peak in the second week of December (38% of checklists), and fall back by early April. In the quietest week (the second week of May) they are still on about 6.4% of checklists.

When to look

Numbers buildOct 8-14the second week of October

PeakDec 8-14the second week of December

Fall back byApr 1-7early April

FewestMay 8-14the second week of May

Best: the second week of December. Here all year; numbers build from the second week of October and fall back by early April. Peak: on about 38% of Colorado checklists.

Janpeak season
Febpeak season
Marpeak season
Aprcommon
Mayuncommon
Jununcommon
Juluncommon
Auguncommon
Sepuncommon
Octpeak season
Novpeak season
Decpeak season

Darker months: more checklists report it. Outlined: peak month.

Juncos in Colorado, species by species

Species	First arrivals	Common by	Peak	Most gone by	Peak %
Dark-eyed Junco	Oct 8-14	Oct 8-14	Dec 8-14	Apr 1-7	38%

Dark-eyed Junco

Share of complete checklists reporting each species, by week (4 per month). Gaps: fewer than 10 checklists that week.

Frequency is the share of complete checklists in Colorado that listed the bird, 2016–2025. It is not a head count, and it follows where and when people go birding. How to read it.

Where in Colorado

Best counties for Dark-eyed Junco

Share of checklists at the peak

Dolores CountyBest early February · 20 checklists that week, 2,000 in all85%
San Juan CountyBest mid March · 13 checklists that week, 2,012 in all78%
Prowers CountyBest the second week of December · 91 checklists that week, 11,307 in all77%
La Plata CountyBest early November · 292 checklists that week, 21,744 in all71%
Teller CountyBest the second week of December · 101 checklists that week, 11,258 in all67%
El Paso CountyBest early December · 1480 checklists that week, 104,376 in all66%

Common questions

When do juncos arrive in Colorado?: Dark-eyed Juncos are in Colorado all year, but most are here in winter: numbers build from the second week of October, peak in the second week of December (38% of checklists), and fall back by early April. In the quietest week (the second week of May) they are still on about 6.4% of checklists.
When do juncos leave Colorado?: Dark-eyed Juncos never fully leave Colorado: numbers fall back below half their usual rate by early April, but some are still reported in every week, about 6.4% of checklists at the low.
When is the best time to see juncos in Colorado?: The Dark-eyed Junco is reported most often in the second week of December, on about 38% of Colorado checklists.