WhenToBird

Hesperiphona vespertina · Fringillidae

When Do Evening Grosbeaks Arrive in Colorado?

Adult female evening grosbeak
Photo: Some Donkus, CC0 1.0 via iNaturalist

Evening Grosbeaks reach Colorado in early July, are common by mid July, peak in the second week of August (3.0% of checklists), and most are gone by the second week of June.

When to look

First arrivalsJul 1-7early July
Common byJul 15-21mid July
PeakAug 8-14the second week of August
Most gone byJun 8-14the second week of June

Best: the second week of August. First arrivals early July; most are gone by the second week of June. Peak: on about 3.0% of Colorado checklists.

  1. Jancommon
  2. Febcommon
  3. Marcommon
  4. Aprcommon
  5. Maypeak season
  6. Juncommon
  7. Julcommon
  8. Augpeak season
  9. Seppeak season
  10. Octcommon
  11. Novcommon
  12. Deccommon

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

0%1%2%3%4%Jan 1-7: 1.3% of 32254 checklistsJan 8-14: 1.3% of 23278 checklistsJan 15-21: 1.2% of 22933 checklistsJan 22-31: 1.3% of 30856 checklistsFeb 1-7: 1.2% of 21464 checklistsFeb 8-14: 1.4% of 22910 checklistsFeb 15-21: 1.5% of 28739 checklistsFeb 22-28: 1.3% of 21833 checklistsMar 1-7: 1.3% of 23066 checklistsMar 8-14: 1.3% of 23783 checklistsMar 15-21: 1.3% of 24797 checklistsMar 22-31: 1.5% of 38439 checklistsApr 1-7: 1.5% of 31676 checklistsApr 8-14: 1.6% of 35092 checklistsApr 15-21: 1.7% of 36778 checklistsApr 22-30: 2.0% of 50885 checklistsMay 1-7: 2.5% of 44186 checklistsMay 8-14: 2.8% of 49011 checklistsMay 15-21: 2.8% of 40784 checklistsMay 22-31: 2.7% of 53073 checklistsJun 1-7: 2.0% of 32432 checklistsJun 8-14: 1.5% of 29978 checklistsJun 15-21: 1.2% of 29457 checklistsJun 22-30: 1.1% of 36072 checklistsJul 1-7: 1.2% of 28857 checklistsJul 8-14: 1.4% of 27224 checklistsJul 15-21: 1.3% of 27629 checklistsJul 22-31: 1.8% of 37318 checklistsAug 1-7: 2.8% of 25893 checklistsAug 8-14: 3.1% of 24870 checklistsAug 15-21: 3.0% of 24035 checklistsAug 22-31: 2.8% of 35691 checklistsSep 1-7: 2.5% of 27068 checklistsSep 8-14: 2.2% of 26709 checklistsSep 15-21: 2.1% of 26098 checklistsSep 22-30: 2.1% of 31550 checklistsOct 1-7: 1.9% of 24110 checklistsOct 8-14: 1.8% of 23352 checklistsOct 15-21: 1.9% of 21895 checklistsOct 22-31: 1.9% of 28319 checklistsNov 1-7: 1.4% of 21698 checklistsNov 8-14: 1.4% of 21061 checklistsNov 15-21: 1.4% of 19855 checklistsNov 22-30: 1.5% of 25798 checklistsDec 1-7: 1.4% of 18626 checklistsDec 8-14: 1.6% of 19004 checklistsDec 15-21: 1.4% of 23103 checklistsDec 22-31: 1.6% 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. San Miguel CountyBest early March · 110 checklists that week, 8,094 in all34%
  2. La Plata CountyBest early September · 523 checklists that week, 21,744 in all31%
  3. Teller CountyBest late August · 413 checklists that week, 11,258 in all24%
  4. Ouray CountyBest late May · 383 checklists that week, 10,572 in all21%
  5. Archuleta CountyBest the second week of August · 273 checklists that week, 10,365 in all20%
  6. Rio Blanco CountyBest the second week of May · 89 checklists that week, 2,806 in all20%

Best spots

Share of checklists at the peak
  1. NorwoodSan Miguel County, best the second week of May · 29 checklists that week, 1,247 in all95%
  2. Box CanyonOuray County, best early June · 31 checklists that week, 833 in all74%
  3. Casto CreekJefferson County, best mid May · 68 checklists that week, 1,275 in all70%
  4. Crystal CreekEl Paso County, best late August · 31 checklists that week, 652 in all68%
  5. Huck Finn PondLa Plata County, best late August · 127 checklists that week, 2,708 in all57%
  6. Meyer Ranch ParkJefferson County, best late May · 22 checklists that week, 299 in all54%

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

Best time of day

In Colorado, the Evening Grosbeak is most often listed on checklists started between 6 and 8 am (3.1% of those checklists).

0%1%2%3%4%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: 2.8% of 71991 checklists7 am: 3.2% of 159189 checklists8 am: 2.6% of 177206 checklists9 am: 2.1% of 165269 checklists10 am: 1.6% of 141029 checklists11 am: 1.5% of 115283 checklists12 pm: 1.3% of 96068 checklists1 pm: 1.2% of 89512 checklists2 pm: 1.1% of 86319 checklists3 pm: 1.1% of 82496 checklists4 pm: 1.1% of 71648 checklists5 pm: 1.2% of 52445 checklists6 pm: 1.1% 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
January1.3%1.3%1.2%1.3%
February1.2%1.4%1.5%1.3%
March1.3%1.3%1.3%1.5%
April1.5%1.6%1.7%2.0%
May2.5%2.8%2.8%2.7%
June2.0%1.5%1.2%1.1%
July1.2%1.4%1.3%1.8%
August2.8%3.1%3.0%2.8%
September2.5%2.2%2.1%2.1%
October1.9%1.8%1.9%1.9%
November1.4%1.4%1.4%1.5%
December1.4%1.6%1.4%1.6%

Neighboring states

  • Wyoming: arrives early October, 12 weeks later than Colorado
  • New Mexico: arrives mid July, 2 weeks later than Colorado
  • Utah: arrives early October, 12 weeks later than Colorado
  • Montana: arrives early May, 8 weeks earlier than Colorado

Common questions

When do Evening Grosbeaks arrive in Colorado?
Evening Grosbeaks reach Colorado in early July, are common by mid July, peak in the second week of August (3.0% of checklists), and most are gone by the second week of June.
When do Evening Grosbeaks leave Colorado?
Most Evening Grosbeaks have left Colorado by the second week of June, when reports fall below half their usual rate. Stragglers are still reported until mid June.
When is the best time to see a Evening Grosbeak in Colorado?
The Evening Grosbeak is reported most often in the second week of August, on about 3.0% of Colorado checklists.
Where in Colorado are Evening Grosbeaks seen most often?
By county, San Miguel County, La Plata County, and Teller County have the highest peak reporting rates for the Evening Grosbeak (counties with at least 200 checklists).