WhenToBird

Poecile gambeli · Paridae

When Do Mountain Chickadees Arrive in Colorado?

Adult Mountain Chickadee
Photo: Wendy McCrady, CC BY 4.0 via iNaturalist

The Mountain Chickadee is in Colorado all year. It turns up on about 19% of checklists at its peak (early August) and on 7.7% in its quietest week (early May).

When to look

PresentAll year
Peak weekAug 1-7early August
Quietest weekMay 1-7early May

Best: early August. Here all year. Peak: on about 19% of Colorado checklists.

  1. Jancommon
  2. Febcommon
  3. Marcommon
  4. Aprcommon
  5. Maycommon
  6. Junpeak season
  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%20%Jan 1-7: 13% of 32254 checklistsJan 8-14: 13% of 23278 checklistsJan 15-21: 13% of 22933 checklistsJan 22-31: 13% of 30856 checklistsFeb 1-7: 13% of 21464 checklistsFeb 8-14: 15% of 22910 checklistsFeb 15-21: 14% of 28739 checklistsFeb 22-28: 12% of 21833 checklistsMar 1-7: 12% of 23066 checklistsMar 8-14: 12% of 23783 checklistsMar 15-21: 11% of 24797 checklistsMar 22-31: 9.8% of 38439 checklistsApr 1-7: 9.7% of 31676 checklistsApr 8-14: 9.5% of 35092 checklistsApr 15-21: 8.0% of 36778 checklistsApr 22-30: 8.0% of 50885 checklistsMay 1-7: 7.3% of 44186 checklistsMay 8-14: 7.9% of 49011 checklistsMay 15-21: 8.9% of 40784 checklistsMay 22-31: 11% of 53073 checklistsJun 1-7: 12% of 32432 checklistsJun 8-14: 13% of 29978 checklistsJun 15-21: 13% of 29457 checklistsJun 22-30: 15% of 36072 checklistsJul 1-7: 17% of 28857 checklistsJul 8-14: 19% of 27224 checklistsJul 15-21: 19% of 27629 checklistsJul 22-31: 19% of 37318 checklistsAug 1-7: 19% of 25893 checklistsAug 8-14: 19% of 24870 checklistsAug 15-21: 18% of 24035 checklistsAug 22-31: 18% of 35691 checklistsSep 1-7: 17% of 27068 checklistsSep 8-14: 15% of 26709 checklistsSep 15-21: 17% of 26098 checklistsSep 22-30: 18% of 31550 checklistsOct 1-7: 18% of 24110 checklistsOct 8-14: 15% of 23352 checklistsOct 15-21: 15% of 21895 checklistsOct 22-31: 14% of 28319 checklistsNov 1-7: 13% of 21698 checklistsNov 8-14: 12% of 21061 checklistsNov 15-21: 13% of 19855 checklistsNov 22-30: 13% of 25798 checklistsDec 1-7: 12% of 18626 checklistsDec 8-14: 14% of 19004 checklistsDec 15-21: 14% of 23103 checklistsDec 22-31: 14% 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. Lake CountyBest early January · 17 checklists that week, 2,361 in all86%
  2. Clear Creek CountyBest late February · 68 checklists that week, 8,581 in all81%
  3. Jackson CountyBest late December · 14 checklists that week, 7,472 in all79%
  4. Gilpin CountyBest late December · 33 checklists that week, 4,252 in all78%
  5. San Juan CountyBest early January · 12 checklists that week, 2,012 in all73%
  6. Teller CountyBest mid December · 72 checklists that week, 11,258 in all70%

Best spots

Share of checklists at the peak
  1. Lake QuiviraClear Creek County, best early February · 37 checklists that week, 1,149 in all98%
  2. WardBoulder County, best late January · 23 checklists that week, 259 in all98%
  3. Eagles Nest WildernessSummit County, best early August · 24 checklists that week, 185 in all96%
  4. Pike National ForestEl Paso County, best late July · 21 checklists that week, 434 in all96%
  5. Casto CreekJefferson County, best the second week of September · 20 checklists that week, 1,275 in all95%

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

Best time of day

In Colorado, the Mountain Chickadee is most often listed on checklists started between 6 and 8 am (18% of those checklists).

0%5%10%15%20%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: 17% of 71991 checklists7 am: 18% of 159189 checklists8 am: 16% of 177206 checklists9 am: 14% of 165269 checklists10 am: 13% of 141029 checklists11 am: 12% of 115283 checklists12 pm: 11% of 96068 checklists1 pm: 11% of 89512 checklists2 pm: 11% of 86319 checklists3 pm: 11% of 82496 checklists4 pm: 10% of 71648 checklists5 pm: 9.5% of 52445 checklists6 pm: 8.6% 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
January13%13%13%13%
February13%15%14%12%
March12%12%11%9.8%
April9.7%9.5%8.0%8.0%
May7.3%7.9%8.9%11%
June12%13%13%15%
July17%19%19%19%
August19%19%18%18%
September17%15%17%18%
October18%15%15%14%
November13%12%13%13%
December12%14%14%14%

Neighboring states

  • Wyoming: all year, most in fall, peaks early September
  • New Mexico: year-round, peaks mid October
  • Utah: all year, most in summer, peaks late July
  • Arizona: summer visitor, peaks early September

Common questions

When do Mountain Chickadees arrive in Colorado?
The Mountain Chickadee is in Colorado all year. It turns up on about 19% of checklists at its peak (early August) and on 7.7% in its quietest week (early May).
When do Mountain Chickadees leave Colorado?
The Mountain Chickadee does not leave Colorado: it is reported all year, from 7.7% of checklists in early May to 19% in early August.
When is the best time to see a Mountain Chickadee in Colorado?
The Mountain Chickadee is reported most often in early August, on about 19% of Colorado checklists.
Where in Colorado are Mountain Chickadees seen most often?
By county, Lake County, Clear Creek County, and Jackson County have the highest peak reporting rates for the Mountain Chickadee (counties with at least 200 checklists).