WhenToBird

Cyanocitta stelleri · Corvidae

When Do Steller's Jays Arrive in Colorado?

Adult Steller's Jay
Photo: Steven Smethurst, CC0 1.0 via iNaturalist

Steller's Jays are in Colorado all year, but most are here in fall: numbers build from the second week of July, peak in late September (14% of checklists), and fall back by early November. In the quietest week (late April) they are still on about 4.9% of checklists.

When to look

Numbers buildJul 8-14the second week of July
PeakSep 22-30late September
Fall back byNov 1-7early November
FewestApr 22-30late April

Best: late September. Here all year; numbers build from the second week of July and fall back by early November. Peak: on about 14% of Colorado checklists.

  1. Jancommon
  2. Febcommon
  3. Marcommon
  4. Aprcommon
  5. Maycommon
  6. Juncommon
  7. Julpeak season
  8. Augpeak season
  9. Seppeak season
  10. Octpeak season
  11. Novcommon
  12. Deccommon

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

0%5%10%15%Jan 1-7: 7.2% of 32254 checklistsJan 8-14: 7.5% of 23278 checklistsJan 15-21: 7.7% of 22933 checklistsJan 22-31: 7.7% of 30856 checklistsFeb 1-7: 6.8% of 21464 checklistsFeb 8-14: 8.0% of 22910 checklistsFeb 15-21: 8.6% of 28739 checklistsFeb 22-28: 7.4% of 21833 checklistsMar 1-7: 7.7% of 23066 checklistsMar 8-14: 8.3% of 23783 checklistsMar 15-21: 7.7% of 24797 checklistsMar 22-31: 7.1% of 38439 checklistsApr 1-7: 7.0% of 31676 checklistsApr 8-14: 6.8% of 35092 checklistsApr 15-21: 5.3% of 36778 checklistsApr 22-30: 4.9% of 50885 checklistsMay 1-7: 4.7% of 44186 checklistsMay 8-14: 5.3% of 49011 checklistsMay 15-21: 6.4% of 40784 checklistsMay 22-31: 7.7% of 53073 checklistsJun 1-7: 8.8% of 32432 checklistsJun 8-14: 9.3% of 29978 checklistsJun 15-21: 8.8% of 29457 checklistsJun 22-30: 9.0% of 36072 checklistsJul 1-7: 9.0% of 28857 checklistsJul 8-14: 9.8% of 27224 checklistsJul 15-21: 10% of 27629 checklistsJul 22-31: 11% of 37318 checklistsAug 1-7: 11% of 25893 checklistsAug 8-14: 12% of 24870 checklistsAug 15-21: 12% of 24035 checklistsAug 22-31: 13% of 35691 checklistsSep 1-7: 13% of 27068 checklistsSep 8-14: 13% of 26709 checklistsSep 15-21: 14% of 26098 checklistsSep 22-30: 14% of 31550 checklistsOct 1-7: 15% of 24110 checklistsOct 8-14: 12% of 23352 checklistsOct 15-21: 11% of 21895 checklistsOct 22-31: 10% of 28319 checklistsNov 1-7: 9.7% of 21698 checklistsNov 8-14: 9.0% of 21061 checklistsNov 15-21: 8.8% of 19855 checklistsNov 22-30: 8.3% of 25798 checklistsDec 1-7: 7.3% of 18626 checklistsDec 8-14: 8.1% of 19004 checklistsDec 15-21: 8.2% of 23103 checklistsDec 22-31: 7.8% of 30802 checklistsJanFebMarAprMayJunJulAugSepOctNovDec
Share of complete checklists reporting it, by week (4 per month). Grey bars: fewer than 10 checklists, not counted.

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.

JanFebMarAprMayJunJulAugSepOctNovDec
today
Second week of November

Each county is shaded by the share of complete checklists there that listed the bird, blended with the weeks either side. Darker is more often. It follows where people watch birds, not how many birds there are. How to read it.

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Where in Colorado

Best counties

Share of checklists at the peak
  1. Teller CountyBest late September · 322 checklists that week, 11,258 in all70%
  2. Clear Creek CountyBest early December · 53 checklists that week, 8,581 in all69%
  3. Lake CountyBest late December · 21 checklists that week, 2,361 in all67%
  4. Custer CountyBest the second week of September · 89 checklists that week, 3,017 in all59%
  5. Gilpin CountyBest the second week of November · 17 checklists that week, 4,252 in all57%
  6. Hinsdale CountyBest the second week of October · 19 checklists that week, 2,303 in all54%

Best spots

Share of checklists at the peak
  1. Lake QuiviraClear Creek County, best the second week of November · 26 checklists that week, 1,149 in all97%
  2. WardBoulder County, best late January · 23 checklists that week, 259 in all96%
  3. AllensparkBoulder County, best the second week of January · 33 checklists that week, 466 in all94%
  4. State Forest State ParkJackson County, best mid April · 66 checklists that week, 748 in all94%
  5. Rocky Mountain National Park (Chiquita Creek)Larimer County, best the second week of August · 28 checklists that week, 484 in all93%
  6. Staunton State ParkJefferson County, best late August · 23 checklists that week, 869 in all92%

Busy spots report more of everything; compare the checklist counts before you drive anywhere.

Best time of day

In Colorado, the Steller's Jay is most often listed on checklists started between 6 and 8 am (12% of those checklists).

0%5%10%15%12 am: too few checklists (512) to judge1 am: too few checklists (468) to judge2 am: too few checklists (513) to judge3 am: too few checklists (656) to judge4 am: too few checklists (1918) to judge5 am: too few checklists (16045) to judge6 am: 10% of 71991 checklists7 am: 12% of 159189 checklists8 am: 11% of 177206 checklists9 am: 9.9% of 165269 checklists10 am: 9.3% of 141029 checklists11 am: 8.5% of 115283 checklists12 pm: 7.6% of 96068 checklists1 pm: 7.6% of 89512 checklists2 pm: 7.2% of 86319 checklists3 pm: 6.4% of 82496 checklists4 pm: 6.0% of 71648 checklists5 pm: 6.0% of 52445 checklists6 pm: 5.0% of 40199 checklists7 pm: too few checklists (24246) to judge8 pm: too few checklists (7986) to judge9 pm: too few checklists (2004) to judge10 pm: too few checklists (888) to judge11 pm: too few checklists (450) to judge12a3a6a9a12p3p6p9p
Share of checklists started in each local hour that reported it. It reflects when people go birding as well as when birds are active. Grey hours have too few checklists (under 2% of the state’s, or under 200) to judge.
Week-by-week table
MonthDays 1-78-1415-2122-end
January7.2%7.5%7.7%7.7%
February6.8%8.0%8.6%7.4%
March7.7%8.3%7.7%7.1%
April7.0%6.8%5.3%4.9%
May4.7%5.3%6.4%7.7%
June8.8%9.3%8.8%9.0%
July9.0%9.8%10%11%
August11%12%12%13%
September13%13%14%14%
October15%12%11%10%
November9.7%9.0%8.8%8.3%
December7.3%8.1%8.2%7.8%

Neighboring states

  • Wyoming: arrives mid May, 7 weeks earlier than Colorado
  • New Mexico: year-round, peaks late August
  • Utah: arrives early July, 1 week earlier than Colorado
  • Arizona: arrives late February, 18 weeks earlier than Colorado

Common questions

When do Steller's Jays arrive in Colorado?
Steller's Jays are in Colorado all year, but most are here in fall: numbers build from the second week of July, peak in late September (14% of checklists), and fall back by early November. In the quietest week (late April) they are still on about 4.9% of checklists.
When do Steller's Jays leave Colorado?
Steller's Jays never fully leave Colorado: numbers fall back below half their usual rate by early November, but some are still reported in every week, about 4.9% of checklists at the low.
When is the best time to see a Steller's Jay in Colorado?
The Steller's Jay is reported most often in late September, on about 14% of Colorado checklists.
Where in Colorado are Steller's Jays seen most often?
By county, Teller County, Clear Creek County, and Lake County have the highest peak reporting rates for the Steller's Jay (counties with at least 200 checklists).