WhenToBird

Agelaius phoeniceus · Icteridae

When Do Red-winged Blackbirds Arrive in Montana?

Adult male Red-winged Blackbird
Photo: infiniteuniverse, CC0 1.0 via iNaturalist

Red-winged Blackbirds are in Montana all year, but most are here in spring: numbers build from mid March, peak in early May (54% of checklists), and fall back by the second week of July. In the quietest week (late November) they are still on about 3.2% of checklists.

When to look

Numbers buildMar 15-21mid March
PeakMay 1-7early May
Fall back byJul 8-14the second week of July
FewestNov 22-30late November

Best: early May. Here all year; numbers build from mid March and fall back by the second week of July. Peak: on about 54% of Montana checklists.

  1. Janrare
  2. Febuncommon
  3. Marcommon
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julcommon
  8. Auguncommon
  9. Sepuncommon
  10. Octuncommon
  11. Novrare
  12. Decrare

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

0%20%40%60%Jan 1-7: 3.9% of 7987 checklistsJan 8-14: 3.5% of 5561 checklistsJan 15-21: 3.8% of 5613 checklistsJan 22-31: 3.9% of 7881 checklistsFeb 1-7: 4.7% of 5018 checklistsFeb 8-14: 6.7% of 5598 checklistsFeb 15-21: 9.0% of 7247 checklistsFeb 22-28: 14% of 5531 checklistsMar 1-7: 21% of 6110 checklistsMar 8-14: 28% of 6623 checklistsMar 15-21: 33% of 7687 checklistsMar 22-31: 39% of 11095 checklistsApr 1-7: 44% of 7774 checklistsApr 8-14: 46% of 8785 checklistsApr 15-21: 49% of 9684 checklistsApr 22-30: 53% of 13805 checklistsMay 1-7: 54% of 11847 checklistsMay 8-14: 54% of 13547 checklistsMay 15-21: 51% of 13019 checklistsMay 22-31: 45% of 20456 checklistsJun 1-7: 42% of 12993 checklistsJun 8-14: 38% of 11594 checklistsJun 15-21: 38% of 11159 checklistsJun 22-30: 35% of 13786 checklistsJul 1-7: 33% of 9584 checklistsJul 8-14: 29% of 9078 checklistsJul 15-21: 27% of 7905 checklistsJul 22-31: 22% of 10906 checklistsAug 1-7: 20% of 7335 checklistsAug 8-14: 16% of 6868 checklistsAug 15-21: 15% of 6866 checklistsAug 22-31: 13% of 10076 checklistsSep 1-7: 13% of 7670 checklistsSep 8-14: 14% of 7490 checklistsSep 15-21: 17% of 6804 checklistsSep 22-30: 19% of 8016 checklistsOct 1-7: 19% of 5996 checklistsOct 8-14: 16% of 6156 checklistsOct 15-21: 13% of 5742 checklistsOct 22-31: 7.7% of 7790 checklistsNov 1-7: 5.1% of 5353 checklistsNov 8-14: 4.2% of 5475 checklistsNov 15-21: 3.3% of 4603 checklistsNov 22-30: 3.4% of 6067 checklistsDec 1-7: 2.9% of 4362 checklistsDec 8-14: 3.4% of 4467 checklistsDec 15-21: 3.6% of 5328 checklistsDec 22-31: 3.3% of 6672 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 Montana 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 Montana

Best counties

Share of checklists at the peak
  1. Wibaux CountyBest mid May · 31 checklists that week, 435 in all83%
  2. Daniels CountyBest late July · 12 checklists that week, 481 in all71%
  3. Fallon CountyBest early July · 25 checklists that week, 542 in all70%
  4. Cascade CountyBest the second week of May · 440 checklists that week, 16,190 in all68%
  5. Lake CountyBest early May · 563 checklists that week, 19,478 in all67%
  6. Pondera CountyBest late May · 21 checklists that week, 659 in all66%

Best spots

Share of checklists at the peak
  1. Pattee CreekMissoula County, best late March · 35 checklists that week, 1,423 in all100%
  2. Pablo ReservoirLake County, best mid May · 26 checklists that week, 791 in all99%
  3. Lee Metcalf National Wildlife Refuge (northeast)Ravalli County, best early April · 23 checklists that week, 838 in all99%
  4. Cattail Creek ParkGallatin County, best late May · 34 checklists that week, 1,169 in all99%

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

Best time of day

In Montana, the Red-winged Blackbird is most often listed on checklists started between 6 and 8 am (37% of those checklists).

0%10%20%30%40%12 am: too few checklists (183) to judge1 am: too few checklists (169) to judge2 am: too few checklists (163) to judge3 am: too few checklists (212) to judge4 am: too few checklists (503) to judge5 am: too few checklists (4022) to judge6 am: 39% of 12719 checklists7 am: 37% of 31202 checklists8 am: 30% of 47646 checklists9 am: 28% of 44624 checklists10 am: 25% of 40704 checklists11 am: 23% of 33825 checklists12 pm: 21% of 29407 checklists1 pm: 20% of 27959 checklists2 pm: 20% of 26928 checklists3 pm: 21% of 25313 checklists4 pm: 25% of 22151 checklists5 pm: 30% of 16884 checklists6 pm: 35% of 13780 checklists7 pm: 35% of 9926 checklists8 pm: too few checklists (5765) to judge9 pm: too few checklists (2099) to judge10 pm: too few checklists (595) to judge11 pm: too few checklists (230) 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
January3.9%3.5%3.8%3.9%
February4.7%6.7%9.0%14%
March21%28%33%39%
April44%46%49%53%
May54%54%51%45%
June42%38%38%35%
July33%29%27%22%
August20%16%15%13%
September13%14%17%19%
October19%16%13%7.7%
November5.1%4.2%3.3%3.4%
December2.9%3.4%3.6%3.3%

Neighboring states

  • Idaho: arrives mid February, 4 weeks earlier than Montana
  • Wyoming: arrives mid February, 4 weeks earlier than Montana
  • Utah: arrives late February, 3 weeks earlier than Montana
  • Washington: arrives mid February, 4 weeks earlier than Montana

Common questions

When do Red-winged Blackbirds arrive in Montana?
Red-winged Blackbirds are in Montana all year, but most are here in spring: numbers build from mid March, peak in early May (54% of checklists), and fall back by the second week of July. In the quietest week (late November) they are still on about 3.2% of checklists.
When do Red-winged Blackbirds leave Montana?
Red-winged Blackbirds never fully leave Montana: numbers fall back below half their usual rate by the second week of July, but some are still reported in every week, about 3.2% of checklists at the low.
When is the best time to see a Red-winged Blackbird in Montana?
The Red-winged Blackbird is reported most often in early May, on about 54% of Montana checklists.
Where in Montana are Red-winged Blackbirds seen most often?
By county, Wibaux County, Daniels County, and Fallon County have the highest peak reporting rates for the Red-winged Blackbird (counties with at least 200 checklists).