WhenToBird

Hydroprogne caspia · Laridae

When Do Caspian Terns Arrive in Ohio?

Adult Caspian Tern
Photo: Daughter Dad, CC BY 4.0 via iNaturalist

Caspian Terns reach Ohio in early April, are common by the second week of April, peak in mid August (9.1% of checklists), and most are gone by mid September.

When to look

First arrivalsApr 1-7early April
Common byApr 8-14the second week of April
PeakAug 15-21mid August
Most gone bySep 15-21mid September

Best: mid August. First arrivals early April; most are gone by mid September. Peak: on about 9.1% of Ohio checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marrare
  4. Aprcommon
  5. Maycommon
  6. Jununcommon
  7. Julcommon
  8. Augpeak season
  9. Seppeak season
  10. Octrare
  11. Novnot usually seen
  12. Decnot usually seen

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

0%5%10%Jan 1-7: 0% of 46637 checklistsJan 8-14: 0% of 31056 checklistsJan 15-21: 0% of 30129 checklistsJan 22-31: 0% of 38665 checklistsFeb 1-7: 0% of 27203 checklistsFeb 8-14: 0% of 30626 checklistsFeb 15-21: 0% of 40705 checklistsFeb 22-28: 0% of 31391 checklistsMar 1-7: 0% of 32914 checklistsMar 8-14: 0% of 33973 checklistsMar 15-21: 0.1% of 33678 checklistsMar 22-31: 0.3% of 49889 checklistsApr 1-7: 1.3% of 41225 checklistsApr 8-14: 2.9% of 47174 checklistsApr 15-21: 4.7% of 47017 checklistsApr 22-30: 4.6% of 73055 checklistsMay 1-7: 5.2% of 80637 checklistsMay 8-14: 5.2% of 102552 checklistsMay 15-21: 3.4% of 64582 checklistsMay 22-31: 1.5% of 52766 checklistsJun 1-7: 1.0% of 29279 checklistsJun 8-14: 1.1% of 25773 checklistsJun 15-21: 0.9% of 23163 checklistsJun 22-30: 1.5% of 27794 checklistsJul 1-7: 3.0% of 23334 checklistsJul 8-14: 3.9% of 22147 checklistsJul 15-21: 4.2% of 20998 checklistsJul 22-31: 5.0% of 29749 checklistsAug 1-7: 6.7% of 22899 checklistsAug 8-14: 8.5% of 21972 checklistsAug 15-21: 9.8% of 22215 checklistsAug 22-31: 9.0% of 35087 checklistsSep 1-7: 7.1% of 29148 checklistsSep 8-14: 5.4% of 28042 checklistsSep 15-21: 3.0% of 26751 checklistsSep 22-30: 2.0% of 32398 checklistsOct 1-7: 0.9% of 26209 checklistsOct 8-14: 0.4% of 26809 checklistsOct 15-21: 0.4% of 23504 checklistsOct 22-31: 0.2% of 33269 checklistsNov 1-7: 0.1% of 25563 checklistsNov 8-14: 0.1% of 23810 checklistsNov 15-21: 0% of 22127 checklistsNov 22-30: 0% of 29449 checklistsDec 1-7: 0% of 22370 checklistsDec 8-14: 0% of 21581 checklistsDec 15-21: 0.1% of 24232 checklistsDec 22-31: 0% of 36084 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 Ohio 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 Ohio

Best counties

Share of checklists at the peak
  1. Sandusky CountyBest the second week of August · 290 checklists that week, 14,537 in all31%
  2. Ashtabula CountyBest mid August · 230 checklists that week, 12,390 in all30%
  3. Lorain CountyBest the second week of August · 840 checklists that week, 59,913 in all27%
  4. Lucas CountyBest mid August · 1426 checklists that week, 152,906 in all27%
  5. Erie CountyBest mid August · 390 checklists that week, 30,456 in all26%
  6. Delaware CountyBest mid August · 858 checklists that week, 51,114 in all25%

Best spots

Share of checklists at the peak
  1. Conneaut HarborAshtabula County, best late April · 20 checklists that week, 1,284 in all100%
  2. Howard Farms Land Acquisition (west)Lucas County, best mid August · 100 checklists that week, 3,485 in all93%
  3. Huron RangeErie County, best early July · 123 checklists that week, 944 in all90%
  4. Akron City ReservoirGeauga County, best the second week of August · 77 checklists that week, 4,955 in all87%
  5. Maumee Bay State Park (Erie Beach)Lucas County, best late August · 61 checklists that week, 1,537 in all87%
  6. Pickerel Creek Wildlife AreaSandusky County, best late August · 46 checklists that week, 683 in all85%

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

Best time of day

In Ohio, the Caspian Tern is most often listed on checklists started between 6 and 8 am (3.3% of those checklists).

0%2%4%6%12 am: too few checklists (574) to judge1 am: too few checklists (609) to judge2 am: too few checklists (466) to judge3 am: too few checklists (478) to judge4 am: too few checklists (662) to judge5 am: too few checklists (4366) to judge6 am: 4.3% of 43093 checklists7 am: 2.9% of 142017 checklists8 am: 2.1% of 205296 checklists9 am: 2.0% of 196322 checklists10 am: 2.0% of 170882 checklists11 am: 2.1% of 144567 checklists12 pm: 2.3% of 126551 checklists1 pm: 2.5% of 117855 checklists2 pm: 2.5% of 112869 checklists3 pm: 2.4% of 109786 checklists4 pm: 2.3% of 103116 checklists5 pm: 2.7% of 78409 checklists6 pm: 2.9% of 56785 checklists7 pm: 2.6% of 37923 checklists8 pm: too few checklists (14954) to judge9 pm: too few checklists (2710) to judge10 pm: too few checklists (854) to judge11 pm: too few checklists (486) 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
January0%0%0%0%
February0%0%0%0%
March0%0%0.1%0.3%
April1.3%2.9%4.7%4.6%
May5.2%5.2%3.4%1.5%
June1.0%1.1%0.9%1.5%
July3.0%3.9%4.2%5.0%
August6.7%8.5%9.8%9.0%
September7.1%5.4%3.0%2.0%
October0.9%0.4%0.4%0.2%
November0.1%0.1%0%0%
December0%0%0.1%0%

Neighboring states

  • Indiana: arrives late March, 1 week earlier than Ohio
  • Michigan: arrives the second week of April, 1 week later than Ohio
  • Kentucky: arrives mid July, 14 weeks later than Ohio
  • Pennsylvania: arrives the second week of July, 13 weeks later than Ohio

Common questions

When do Caspian Terns arrive in Ohio?
Caspian Terns reach Ohio in early April, are common by the second week of April, peak in mid August (9.1% of checklists), and most are gone by mid September.
When do Caspian Terns leave Ohio?
Most Caspian Terns have left Ohio by mid September, when reports fall below half their usual rate. Stragglers are still reported until early October.
When is the best time to see a Caspian Tern in Ohio?
The Caspian Tern is reported most often in mid August, on about 9.1% of Ohio checklists.
Where in Ohio are Caspian Terns seen most often?
By county, Sandusky County, Ashtabula County, and Lorain County have the highest peak reporting rates for the Caspian Tern (counties with at least 200 checklists).