WhenToBird

Aphelocoma woodhouseii · Corvidae

When Do Woodhouse's Scrub-Jays Arrive in Colorado?

Adult Woodhouse's Scrub-Jay
Photo: Daughter Dad, CC BY 4.0 via iNaturalist

The Woodhouse's Scrub-Jay is in Colorado all year. It turns up on about 10% of checklists at its peak (early October) and on 5.3% in its quietest week (mid June).

When to look

PresentAll year
Peak weekOct 1-7early October
Quietest weekJun 15-21mid June

Best: early October. Here all year. Peak: on about 10% of Colorado checklists.

  1. Janpeak season
  2. Febcommon
  3. Marcommon
  4. Aprcommon
  5. Maycommon
  6. Juncommon
  7. Julcommon
  8. Augpeak season
  9. Seppeak season
  10. Octpeak season
  11. Novpeak season
  12. Decpeak season

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

0%5%10%15%Jan 1-7: 7.9% of 32254 checklistsJan 8-14: 7.6% of 23278 checklistsJan 15-21: 7.3% of 22933 checklistsJan 22-31: 7.4% of 30856 checklistsFeb 1-7: 7.1% of 21464 checklistsFeb 8-14: 7.3% of 22910 checklistsFeb 15-21: 7.7% of 28739 checklistsFeb 22-28: 6.7% of 21833 checklistsMar 1-7: 7.6% of 23066 checklistsMar 8-14: 7.9% of 23783 checklistsMar 15-21: 7.4% of 24797 checklistsMar 22-31: 7.4% of 38439 checklistsApr 1-7: 6.1% of 31676 checklistsApr 8-14: 5.7% of 35092 checklistsApr 15-21: 5.2% of 36778 checklistsApr 22-30: 5.3% of 50885 checklistsMay 1-7: 5.5% of 44186 checklistsMay 8-14: 6.0% of 49011 checklistsMay 15-21: 6.3% of 40784 checklistsMay 22-31: 6.7% of 53073 checklistsJun 1-7: 6.0% of 32432 checklistsJun 8-14: 5.5% of 29978 checklistsJun 15-21: 5.0% of 29457 checklistsJun 22-30: 5.3% of 36072 checklistsJul 1-7: 5.6% of 28857 checklistsJul 8-14: 5.5% of 27224 checklistsJul 15-21: 5.4% of 27629 checklistsJul 22-31: 6.2% of 37318 checklistsAug 1-7: 6.4% of 25893 checklistsAug 8-14: 7.6% of 24870 checklistsAug 15-21: 8.1% of 24035 checklistsAug 22-31: 8.9% of 35691 checklistsSep 1-7: 9.4% of 27068 checklistsSep 8-14: 9.8% of 26709 checklistsSep 15-21: 9.9% of 26098 checklistsSep 22-30: 10% of 31550 checklistsOct 1-7: 10% of 24110 checklistsOct 8-14: 10% of 23352 checklistsOct 15-21: 9.9% of 21895 checklistsOct 22-31: 9.3% of 28319 checklistsNov 1-7: 9.1% of 21698 checklistsNov 8-14: 8.8% of 21061 checklistsNov 15-21: 7.8% of 19855 checklistsNov 22-30: 8.0% of 25798 checklistsDec 1-7: 7.8% of 18626 checklistsDec 8-14: 8.1% of 19004 checklistsDec 15-21: 8.6% of 23103 checklistsDec 22-31: 8.1% 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. Dolores CountyBest early February · 20 checklists that week, 2,000 in all72%
  2. La Plata CountyBest early September · 523 checklists that week, 21,744 in all47%
  3. Las Animas CountyBest mid September · 44 checklists that week, 3,491 in all43%
  4. Montezuma CountyBest early September · 353 checklists that week, 15,992 in all39%
  5. Huerfano CountyBest early June · 159 checklists that week, 3,008 in all36%
  6. Pitkin CountyBest mid November · 259 checklists that week, 15,513 in all35%

Best spots

Share of checklists at the peak
  1. Aiken Canyon PreserveEl Paso County, best late December · 31 checklists that week, 622 in all95%
  2. Ute Valley ParkEl Paso County, best the second week of September · 22 checklists that week, 689 in all94%
  3. Roxborough State ParkDouglas County, best the second week of September · 22 checklists that week, 1,453 in all93%
  4. Red Rocks Park (Ship Rock)Jefferson County, best the second week of January · 84 checklists that week, 1,376 in all92%
  5. Stratton Open SpaceEl Paso County, best mid January · 25 checklists that week, 558 in all91%

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

Best time of day

In Colorado, the Woodhouse's Scrub-Jay is most often listed on checklists started between 6 and 8 am (11% 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: 9.3% of 71991 checklists7 am: 12% of 159189 checklists8 am: 9.6% of 177206 checklists9 am: 8.0% of 165269 checklists10 am: 6.9% of 141029 checklists11 am: 5.9% of 115283 checklists12 pm: 5.5% of 96068 checklists1 pm: 5.6% of 89512 checklists2 pm: 5.4% of 86319 checklists3 pm: 4.8% of 82496 checklists4 pm: 4.4% of 71648 checklists5 pm: 4.8% of 52445 checklists6 pm: 4.6% 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
January7.9%7.6%7.3%7.4%
February7.1%7.3%7.7%6.7%
March7.6%7.9%7.4%7.4%
April6.1%5.7%5.2%5.3%
May5.5%6.0%6.3%6.7%
June6.0%5.5%5.0%5.3%
July5.6%5.5%5.4%6.2%
August6.4%7.6%8.1%8.9%
September9.4%9.8%9.9%10%
October10%10%9.9%9.3%
November9.1%8.8%7.8%8.0%
December7.8%8.1%8.6%8.1%

Neighboring states

  • New Mexico: year-round, peaks early October
  • Utah: year-round, peaks mid October
  • Arizona: year-round, peaks late September
  • Nevada: year-round, peaks mid August

Common questions

When do Woodhouse's Scrub-Jays arrive in Colorado?
The Woodhouse's Scrub-Jay is in Colorado all year. It turns up on about 10% of checklists at its peak (early October) and on 5.3% in its quietest week (mid June).
When do Woodhouse's Scrub-Jays leave Colorado?
The Woodhouse's Scrub-Jay does not leave Colorado: it is reported all year, from 5.3% of checklists in mid June to 10% in early October.
When is the best time to see a Woodhouse's Scrub-Jay in Colorado?
The Woodhouse's Scrub-Jay is reported most often in early October, on about 10% of Colorado checklists.
Where in Colorado are Woodhouse's Scrub-Jays seen most often?
By county, Dolores County, La Plata County, and Las Animas County have the highest peak reporting rates for the Woodhouse's Scrub-Jay (counties with at least 200 checklists).