WhenToBird

Haliaeetus leucocephalus · Accipitridae

When Do Bald Eagles Arrive in Illinois?

Adult Bald Eagle
Photo: Marcel_Pepin, CC BY 4.0 via iNaturalist

Bald Eagles are in Illinois all year, but most are here in winter: numbers build from early November, peak in late January (13% of checklists), and fall back by late March. In the quietest week (mid June) they are still on about 2.4% of checklists.

When to look

Numbers buildNov 1-7early November
PeakJan 22-31late January
Fall back byMar 22-31late March
FewestJun 15-21mid June

Best: late January. Here all year; numbers build from early November and fall back by late March. Peak: on about 13% of Illinois checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marpeak season
  4. Aprcommon
  5. Mayuncommon
  6. Jununcommon
  7. Juluncommon
  8. Auguncommon
  9. Sepcommon
  10. Octcommon
  11. Novcommon
  12. Decpeak season

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

0%5%10%15%Jan 1-7: 11% of 29700 checklistsJan 8-14: 11% of 20189 checklistsJan 15-21: 13% of 19784 checklistsJan 22-31: 13% of 26641 checklistsFeb 1-7: 13% of 20478 checklistsFeb 8-14: 10% of 21967 checklistsFeb 15-21: 11% of 28735 checklistsFeb 22-28: 12% of 24223 checklistsMar 1-7: 11% of 26775 checklistsMar 8-14: 9.8% of 27579 checklistsMar 15-21: 8.8% of 27193 checklistsMar 22-31: 8.2% of 42278 checklistsApr 1-7: 7.2% of 34579 checklistsApr 8-14: 6.6% of 38290 checklistsApr 15-21: 6.2% of 39261 checklistsApr 22-30: 5.9% of 59584 checklistsMay 1-7: 4.9% of 60485 checklistsMay 8-14: 3.9% of 59647 checklistsMay 15-21: 3.3% of 43173 checklistsMay 22-31: 3.4% of 47913 checklistsJun 1-7: 2.4% of 31151 checklistsJun 8-14: 2.6% of 27692 checklistsJun 15-21: 2.1% of 23983 checklistsJun 22-30: 2.3% of 28448 checklistsJul 1-7: 2.8% of 21273 checklistsJul 8-14: 3.4% of 19284 checklistsJul 15-21: 3.7% of 17712 checklistsJul 22-31: 4.0% of 24500 checklistsAug 1-7: 4.7% of 18498 checklistsAug 8-14: 5.1% of 19331 checklistsAug 15-21: 5.0% of 19983 checklistsAug 22-31: 4.8% of 31892 checklistsSep 1-7: 5.0% of 26396 checklistsSep 8-14: 4.5% of 25011 checklistsSep 15-21: 4.8% of 23597 checklistsSep 22-30: 6.1% of 30638 checklistsOct 1-7: 6.2% of 23949 checklistsOct 8-14: 6.3% of 24412 checklistsOct 15-21: 6.8% of 22359 checklistsOct 22-31: 7.8% of 29794 checklistsNov 1-7: 7.6% of 21877 checklistsNov 8-14: 9.1% of 19742 checklistsNov 15-21: 9.1% of 18989 checklistsNov 22-30: 9.3% of 23905 checklistsDec 1-7: 9.2% of 16935 checklistsDec 8-14: 9.2% of 16687 checklistsDec 15-21: 11% of 20931 checklistsDec 22-31: 11% of 29011 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 Illinois 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 Illinois

Best counties

Share of checklists at the peak
  1. Putnam CountyBest the second week of January · 18 checklists that week, 3,333 in all75%
  2. Richland CountyBest early December · 10 checklists that week, 580 in all69%
  3. Wayne CountyBest mid October · 12 checklists that week, 394 in all67%
  4. Fulton CountyBest late January · 38 checklists that week, 5,877 in all64%
  5. Carroll CountyBest the second week of February · 47 checklists that week, 4,152 in all62%
  6. Henderson CountyBest late February · 14 checklists that week, 800 in all61%

Best spots

Share of checklists at the peak
  1. Starved Rock PoolLa Salle County, best late January · 58 checklists that week, 245 in all97%
  2. Pool 21Adams County, best late January · 29 checklists that week, 490 in all96%
  3. Sunset Park & MarinaRock Island County, best mid February · 23 checklists that week, 302 in all92%
  4. Pool 14Rock Island County, best late January · 23 checklists that week, 662 in all91%
  5. Sue and Wes Dixon Waterfowl Refuge at Hennepin & Hopper LakesPutnam County, best early December · 34 checklists that week, 1,924 in all91%

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

Best time of day

In Illinois, the Bald Eagle is most often listed on checklists started between 10 am and 12 pm (8.5% of those checklists).

0%5%10%12 am: too few checklists (484) to judge1 am: too few checklists (631) to judge2 am: too few checklists (485) to judge3 am: too few checklists (610) to judge4 am: too few checklists (2321) to judge5 am: too few checklists (23536) to judge6 am: 4.2% of 95511 checklists7 am: 5.8% of 164584 checklists8 am: 6.8% of 163654 checklists9 am: 7.9% of 141804 checklists10 am: 8.6% of 122882 checklists11 am: 8.3% of 100640 checklists12 pm: 8.0% of 89894 checklists1 pm: 8.4% of 82729 checklists2 pm: 8.3% of 79801 checklists3 pm: 7.3% of 82169 checklists4 pm: 5.9% of 75124 checklists5 pm: 4.3% of 57708 checklists6 pm: 3.1% of 41843 checklists7 pm: too few checklists (20943) to judge8 pm: too few checklists (6131) to judge9 pm: too few checklists (1677) to judge10 pm: too few checklists (843) to judge11 pm: too few checklists (448) 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
January11%11%13%13%
February13%10%11%12%
March11%9.8%8.8%8.2%
April7.2%6.6%6.2%5.9%
May4.9%3.9%3.3%3.4%
June2.4%2.6%2.1%2.3%
July2.8%3.4%3.7%4.0%
August4.7%5.1%5.0%4.8%
September5.0%4.5%4.8%6.1%
October6.2%6.3%6.8%7.8%
November7.6%9.1%9.1%9.3%
December9.2%9.2%11%11%

Neighboring states

  • Indiana: arrives late September, 5 weeks earlier than Illinois
  • Wisconsin: year-round, peaks the second week of March
  • Michigan: year-round, peaks early January
  • Iowa: arrives the second week of November, 1 week later than Illinois

Common questions

When do Bald Eagles arrive in Illinois?
Bald Eagles are in Illinois all year, but most are here in winter: numbers build from early November, peak in late January (13% of checklists), and fall back by late March. In the quietest week (mid June) they are still on about 2.4% of checklists.
When do Bald Eagles leave Illinois?
Bald Eagles never fully leave Illinois: numbers fall back below half their usual rate by late March, but some are still reported in every week, about 2.4% of checklists at the low.
When is the best time to see a Bald Eagle in Illinois?
The Bald Eagle is reported most often in late January, on about 13% of Illinois checklists.
Where in Illinois are Bald Eagles seen most often?
By county, Putnam County, Richland County, and Wayne County have the highest peak reporting rates for the Bald Eagle (counties with at least 200 checklists).