WhenToBird

Melospiza melodia · Passerellidae

When Do Song Sparrows Arrive in Colorado?

Adult Song Sparrow
Photo: Bill Keim, CC BY 4.0 via iNaturalist

Song Sparrows are in Colorado all year, but most are here in spring: numbers build from early March, peak in early May (25% of checklists), and fall back by the second week of July. In the quietest week (mid August) they are still on about 9.7% of checklists.

When to look

Numbers buildMar 1-7early March
PeakMay 1-7early May
Fall back byJul 8-14the second week of July
FewestAug 15-21mid August

Best: early May. Here all year; numbers build from early March and fall back by the second week of July. Peak: on about 25% of Colorado checklists.

  1. Jancommon
  2. Febcommon
  3. Marpeak season
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augcommon
  9. Sepcommon
  10. Octpeak season
  11. Novpeak season
  12. Decpeak season

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

0%10%20%30%Jan 1-7: 19% of 32254 checklistsJan 8-14: 18% of 23278 checklistsJan 15-21: 18% of 22933 checklistsJan 22-31: 17% of 30856 checklistsFeb 1-7: 16% of 21464 checklistsFeb 8-14: 15% of 22910 checklistsFeb 15-21: 14% of 28739 checklistsFeb 22-28: 18% of 21833 checklistsMar 1-7: 20% of 23066 checklistsMar 8-14: 21% of 23783 checklistsMar 15-21: 23% of 24797 checklistsMar 22-31: 24% of 38439 checklistsApr 1-7: 23% of 31676 checklistsApr 8-14: 22% of 35092 checklistsApr 15-21: 22% of 36778 checklistsApr 22-30: 25% of 50885 checklistsMay 1-7: 26% of 44186 checklistsMay 8-14: 25% of 49011 checklistsMay 15-21: 25% of 40784 checklistsMay 22-31: 23% of 53073 checklistsJun 1-7: 22% of 32432 checklistsJun 8-14: 20% of 29978 checklistsJun 15-21: 20% of 29457 checklistsJun 22-30: 20% of 36072 checklistsJul 1-7: 21% of 28857 checklistsJul 8-14: 19% of 27224 checklistsJul 15-21: 19% of 27629 checklistsJul 22-31: 16% of 37318 checklistsAug 1-7: 12% of 25893 checklistsAug 8-14: 10% of 24870 checklistsAug 15-21: 9.3% of 24035 checklistsAug 22-31: 9.9% of 35691 checklistsSep 1-7: 11% of 27068 checklistsSep 8-14: 13% of 26709 checklistsSep 15-21: 13% of 26098 checklistsSep 22-30: 15% of 31550 checklistsOct 1-7: 16% of 24110 checklistsOct 8-14: 19% of 23352 checklistsOct 15-21: 19% of 21895 checklistsOct 22-31: 20% of 28319 checklistsNov 1-7: 20% of 21698 checklistsNov 8-14: 21% of 21061 checklistsNov 15-21: 21% of 19855 checklistsNov 22-30: 21% of 25798 checklistsDec 1-7: 20% of 18626 checklistsDec 8-14: 20% of 19004 checklistsDec 15-21: 21% of 23103 checklistsDec 22-31: 18% 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.

Embed this map on your site

Where in Colorado

Best counties

Share of checklists at the peak
  1. Eagle CountyBest early April · 324 checklists that week, 15,893 in all50%
  2. Alamosa CountyBest the second week of December · 12 checklists that week, 4,206 in all50%
  3. Delta CountyBest early November · 62 checklists that week, 6,509 in all45%
  4. Broomfield CountyBest the second week of May · 601 checklists that week, 16,139 in all45%
  5. Routt CountyBest mid June · 317 checklists that week, 10,504 in all44%
  6. Pitkin CountyBest late April · 425 checklists that week, 15,513 in all43%

Best spots

Share of checklists at the peak
  1. Yampa River PreserveRoutt County, best late May · 25 checklists that week, 203 in all96%
  2. Tinker-Shaffer Reservoir (historical) (The Valley)Jefferson County, best mid May · 37 checklists that week, 938 in all96%
  3. Mount Ouray State Wildlife AreaChaffee County, best mid January · 21 checklists that week, 793 in all93%
  4. City LandArapahoe County, best mid April · 75 checklists that week, 802 in all93%

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

Best time of day

In Colorado, the Song Sparrow is most often listed on checklists started between 7 and 9 am (24% of those checklists).

0%10%20%30%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: 24% of 71991 checklists7 am: 24% of 159189 checklists8 am: 24% of 177206 checklists9 am: 23% of 165269 checklists10 am: 20% of 141029 checklists11 am: 17% of 115283 checklists12 pm: 16% of 96068 checklists1 pm: 15% of 89512 checklists2 pm: 15% of 86319 checklists3 pm: 15% of 82496 checklists4 pm: 15% of 71648 checklists5 pm: 14% of 52445 checklists6 pm: 14% 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
January19%18%18%17%
February16%15%14%18%
March20%21%23%24%
April23%22%22%25%
May26%25%25%23%
June22%20%20%20%
July21%19%19%16%
August12%10%9.3%9.9%
September11%13%13%15%
October16%19%19%20%
November20%21%21%21%
December20%20%21%18%

Neighboring states

  • Wyoming: arrives late March, 3 weeks later than Colorado
  • New Mexico: arrives mid September, 22 weeks earlier than Colorado
  • Utah: year-round, peaks late May
  • Nebraska: arrives mid March, 2 weeks later than Colorado

Common questions

When do Song Sparrows arrive in Colorado?
Song Sparrows are in Colorado all year, but most are here in spring: numbers build from early March, peak in early May (25% of checklists), and fall back by the second week of July. In the quietest week (mid August) they are still on about 9.7% of checklists.
When do Song Sparrows leave Colorado?
Song Sparrows never fully leave Colorado: numbers fall back below half their usual rate by the second week of July, but some are still reported in every week, about 9.7% of checklists at the low.
When is the best time to see a Song Sparrow in Colorado?
The Song Sparrow is reported most often in early May, on about 25% of Colorado checklists.
Where in Colorado are Song Sparrows seen most often?
By county, Eagle County, Alamosa County, and Delta County have the highest peak reporting rates for the Song Sparrow (counties with at least 200 checklists).