WhenToBird

2 bluebird species in Colorado

When Do Bluebirds Arrive in Colorado?

Adult male Mountain Bluebird
Photo: Josiah Londerée, CC BY 4.0 via iNaturalist

Mountain Bluebirds and Western Bluebirds are the bluebirds you are most likely to see in Colorado. Mountain Bluebirds are winter birds in Colorado: the first arrive in late February, they are common by early March, peak in late March (7.7% of checklists), and most are gone by late October.

When to look

First arrivalsFeb 22-28late February
Common byMar 1-7early March
PeakMar 22-31late March
Most gone byOct 22-31late October

Best: late March. First arrivals late February; most are gone by late October. Peak: on about 7.7% of Colorado checklists.

  1. Januncommon
  2. Febuncommon
  3. Marpeak season
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augcommon
  9. Seppeak season
  10. Octpeak season
  11. Novuncommon
  12. Decuncommon

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

Bluebirds in Colorado, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
Mountain BluebirdFeb 22-28Mar 1-7Mar 22-31Oct 22-317.7%
Western BluebirdMar 1-7Mar 8-14Apr 8-14Oct 15-213.8%
0%5%10%Mountain BluebirdWestern BluebirdJanFebMarAprMayJunJulAugSepOctNovDec
  • Mountain Bluebird
  • Western Bluebird
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 Mountain Bluebird

Share of checklists at the peak
  1. Conejos CountyBest the second week of March · 28 checklists that week, 1,636 in all48%
  2. Baca CountyBest early November · 16 checklists that week, 3,209 in all47%
  3. Dolores CountyBest mid April · 64 checklists that week, 2,000 in all45%
  4. Ouray CountyBest early April · 172 checklists that week, 10,572 in all42%
  5. Park CountyBest early April · 184 checklists that week, 11,432 in all37%
  6. Huerfano CountyBest late November · 42 checklists that week, 3,008 in all37%

Common questions

When do bluebirds arrive in Colorado?
Mountain Bluebirds are winter birds in Colorado: the first arrive in late February, they are common by early March, peak in late March (7.7% of checklists), and most are gone by late October.
When do bluebirds leave Colorado?
Most Mountain Bluebirds have left Colorado by late October, when reports fall below half their usual rate. Stragglers are still reported until the second week of November.
When is the best time to see bluebirds in Colorado?
The Mountain Bluebird is reported most often in late March, on about 7.7% of Colorado checklists.
Which bluebirds are in Colorado?
Mountain Bluebird and Western Bluebird are reported regularly; the Mountain Bluebird is the most common.