WhenToBird

Molothrus ater · Icteridae

When Do Brown-headed Cowbirds Arrive in Florida?

Adult female Brown-headed Cowbird
Photo: Nicole, CC BY 4.0 via iNaturalist

Brown-headed Cowbirds reach Florida in late September, are common by late October, peak in early April (6.3% of checklists), and most are gone by the second week of July.

When to look

First arrivalsSep 22-30late September
Common byOct 22-31late October
PeakApr 1-7early April
Most gone byJul 8-14the second week of July

Best: early April. First arrivals late September; most are gone by the second week of July. Peak: on about 6.3% of Florida checklists.

  1. Jancommon
  2. Febpeak season
  3. Marpeak season
  4. Aprpeak season
  5. Maypeak season
  6. Juncommon
  7. Julcommon
  8. Auguncommon
  9. Sepuncommon
  10. Octcommon
  11. Novcommon
  12. Deccommon

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

0%2%4%6%8%Jan 1-7: 3.5% of 74446 checklistsJan 8-14: 3.4% of 60074 checklistsJan 15-21: 3.6% of 62945 checklistsJan 22-31: 3.9% of 84954 checklistsFeb 1-7: 4.5% of 59204 checklistsFeb 8-14: 4.6% of 63259 checklistsFeb 15-21: 4.9% of 77150 checklistsFeb 22-28: 5.7% of 62850 checklistsMar 1-7: 5.9% of 58560 checklistsMar 8-14: 6.0% of 57756 checklistsMar 15-21: 6.2% of 54898 checklistsMar 22-31: 6.3% of 76702 checklistsApr 1-7: 6.2% of 55096 checklistsApr 8-14: 6.3% of 55892 checklistsApr 15-21: 6.2% of 59358 checklistsApr 22-30: 6.1% of 73124 checklistsMay 1-7: 5.8% of 47915 checklistsMay 8-14: 5.2% of 44114 checklistsMay 15-21: 5.1% of 31858 checklistsMay 22-31: 4.7% of 40723 checklistsJun 1-7: 4.6% of 31668 checklistsJun 8-14: 4.3% of 27802 checklistsJun 15-21: 4.3% of 26698 checklistsJun 22-30: 4.0% of 32346 checklistsJul 1-7: 3.4% of 23826 checklistsJul 8-14: 2.9% of 23071 checklistsJul 15-21: 2.4% of 22903 checklistsJul 22-31: 1.8% of 32952 checklistsAug 1-7: 1.7% of 25093 checklistsAug 8-14: 1.3% of 24888 checklistsAug 15-21: 1.3% of 26030 checklistsAug 22-31: 1.1% of 38612 checklistsSep 1-7: 1.1% of 31023 checklistsSep 8-14: 1.0% of 30022 checklistsSep 15-21: 1.0% of 31611 checklistsSep 22-30: 1.4% of 42108 checklistsOct 1-7: 1.7% of 36219 checklistsOct 8-14: 2.0% of 43113 checklistsOct 15-21: 2.4% of 40987 checklistsOct 22-31: 2.6% of 53457 checklistsNov 1-7: 2.7% of 38587 checklistsNov 8-14: 2.8% of 39208 checklistsNov 15-21: 2.7% of 39729 checklistsNov 22-30: 2.8% of 54965 checklistsDec 1-7: 2.8% of 42070 checklistsDec 8-14: 3.4% of 43424 checklistsDec 15-21: 3.2% of 50581 checklistsDec 22-31: 3.1% of 82405 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 Florida 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 Florida

Best counties

Share of checklists at the peak
  1. Gadsden CountyBest mid April · 108 checklists that week, 3,574 in all40%
  2. Dixie CountyBest mid June · 35 checklists that week, 2,113 in all36%
  3. Columbia CountyBest the second week of June · 61 checklists that week, 5,568 in all28%
  4. Franklin CountyBest mid April · 762 checklists that week, 20,336 in all26%
  5. Putnam CountyBest early April · 150 checklists that week, 4,966 in all26%
  6. Santa Rosa CountyBest the second week of April · 428 checklists that week, 15,001 in all25%

Best spots

Share of checklists at the peak
  1. Tom Renick ParkVolusia County, best early March · 41 checklists that week, 1,941 in all86%
  2. Lake DestinySeminole County, best the second week of March · 21 checklists that week, 1,410 in all72%
  3. Everglades National Park (Bradley Key)Monroe County, best late April · 20 checklists that week, 518 in all71%

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

Best time of day

In Florida, the Brown-headed Cowbird is most often listed on checklists started between 6 and 8 am (6.0% of those checklists).

0%2%4%6%8%12 am: too few checklists (771) to judge1 am: too few checklists (771) to judge2 am: too few checklists (701) to judge3 am: too few checklists (752) to judge4 am: too few checklists (1378) to judge5 am: too few checklists (9462) to judge6 am: 5.6% of 94591 checklists7 am: 6.1% of 296183 checklists8 am: 5.4% of 319987 checklists9 am: 4.3% of 254830 checklists10 am: 3.3% of 209480 checklists11 am: 2.8% of 163924 checklists12 pm: 2.7% of 133478 checklists1 pm: 2.7% of 125012 checklists2 pm: 3.0% of 125299 checklists3 pm: 3.3% of 131072 checklists4 pm: 3.1% of 134410 checklists5 pm: 2.7% of 113373 checklists6 pm: 2.2% of 69886 checklists7 pm: too few checklists (37509) to judge8 pm: too few checklists (8966) to judge9 pm: too few checklists (2093) to judge10 pm: too few checklists (1485) to judge11 pm: too few checklists (862) 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
January3.5%3.4%3.6%3.9%
February4.5%4.6%4.9%5.7%
March5.9%6.0%6.2%6.3%
April6.2%6.3%6.2%6.1%
May5.8%5.2%5.1%4.7%
June4.6%4.3%4.3%4.0%
July3.4%2.9%2.4%1.8%
August1.7%1.3%1.3%1.1%
September1.1%1.0%1.0%1.4%
October1.7%2.0%2.4%2.6%
November2.7%2.8%2.7%2.8%
December2.8%3.4%3.2%3.1%

Neighboring states

  • Georgia: arrives mid March, 23 weeks later than Florida
  • South Carolina: arrives mid March, 23 weeks later than Florida
  • Alabama: arrives early March, 21 weeks later than Florida
  • Mississippi: arrives the second week of March, 22 weeks later than Florida

Common questions

When do Brown-headed Cowbirds arrive in Florida?
Brown-headed Cowbirds reach Florida in late September, are common by late October, peak in early April (6.3% of checklists), and most are gone by the second week of July.
When do Brown-headed Cowbirds leave Florida?
Most Brown-headed Cowbirds have left Florida by the second week of July, when reports fall below half their usual rate. Stragglers are still reported until the second week of August.
When is the best time to see a Brown-headed Cowbird in Florida?
The Brown-headed Cowbird is reported most often in early April, on about 6.3% of Florida checklists.
Where in Florida are Brown-headed Cowbirds seen most often?
By county, Gadsden County, Dixie County, and Columbia County have the highest peak reporting rates for the Brown-headed Cowbird (counties with at least 200 checklists).