WhenToBird

Hydroprogne caspia · Laridae

When Do Caspian Terns Arrive in Texas?

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

Caspian Terns are winter birds in Texas: the first arrive in mid June, they are common by the second week of September, peak in the second week of November (3.5% of checklists), and most are gone by early May.

When to look

First arrivalsJun 15-21mid June
Common bySep 8-14the second week of September
PeakNov 8-14the second week of November
Most gone byMay 1-7early May

Best: the second week of November. First arrivals mid June; most are gone by early May. Peak: on about 3.5% of Texas checklists.

  1. Jancommon
  2. Febcommon
  3. Marpeak season
  4. Aprpeak season
  5. Maycommon
  6. Jununcommon
  7. Julcommon
  8. Augcommon
  9. Sepcommon
  10. Octpeak season
  11. Novpeak season
  12. Decpeak season

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

0%2%4%6%Jan 1-7: 2.3% of 66038 checklistsJan 8-14: 2.3% of 52445 checklistsJan 15-21: 2.3% of 52985 checklistsJan 22-31: 2.3% of 71020 checklistsFeb 1-7: 2.3% of 52306 checklistsFeb 8-14: 2.1% of 55887 checklistsFeb 15-21: 1.8% of 69016 checklistsFeb 22-28: 2.6% of 52998 checklistsMar 1-7: 2.5% of 50836 checklistsMar 8-14: 2.7% of 51749 checklistsMar 15-21: 2.7% of 53731 checklistsMar 22-31: 2.7% of 82049 checklistsApr 1-7: 2.5% of 65854 checklistsApr 8-14: 2.7% of 78434 checklistsApr 15-21: 2.8% of 92302 checklistsApr 22-30: 2.4% of 122878 checklistsMay 1-7: 1.6% of 74592 checklistsMay 8-14: 1.1% of 61008 checklistsMay 15-21: 1.1% of 43365 checklistsMay 22-31: 1.1% of 52736 checklistsJun 1-7: 1.0% of 31643 checklistsJun 8-14: 1.0% of 30131 checklistsJun 15-21: 1.3% of 26802 checklistsJun 22-30: 1.4% of 32822 checklistsJul 1-7: 1.2% of 27213 checklistsJul 8-14: 1.5% of 24555 checklistsJul 15-21: 1.5% of 24146 checklistsJul 22-31: 1.6% of 34536 checklistsAug 1-7: 1.4% of 25764 checklistsAug 8-14: 1.4% of 26347 checklistsAug 15-21: 1.5% of 28431 checklistsAug 22-31: 1.5% of 42838 checklistsSep 1-7: 1.4% of 35070 checklistsSep 8-14: 1.8% of 33893 checklistsSep 15-21: 2.2% of 32572 checklistsSep 22-30: 2.1% of 43771 checklistsOct 1-7: 2.2% of 34143 checklistsOct 8-14: 2.1% of 37563 checklistsOct 15-21: 2.1% of 36263 checklistsOct 22-31: 2.6% of 49170 checklistsNov 1-7: 3.2% of 43301 checklistsNov 8-14: 4.2% of 48744 checklistsNov 15-21: 2.8% of 42213 checklistsNov 22-30: 2.5% of 54455 checklistsDec 1-7: 3.0% of 40166 checklistsDec 8-14: 2.8% of 41035 checklistsDec 15-21: 2.4% of 46983 checklistsDec 22-31: 2.3% of 73015 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 Texas 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 Texas

Best counties

Share of checklists at the peak
  1. Kleberg CountyBest mid July · 104 checklists that week, 9,722 in all24%
  2. Kenedy CountyBest early August · 10 checklists that week, 2,652 in all22%
  3. Starr CountyBest late March · 520 checklists that week, 14,693 in all20%
  4. Willacy CountyBest late September · 25 checklists that week, 4,072 in all19%
  5. Refugio CountyBest the second week of July · 26 checklists that week, 3,809 in all18%
  6. Zapata CountyBest late August · 12 checklists that week, 3,836 in all18%

Best spots

Share of checklists at the peak
  1. Lower Rio Grande Valley National Wildlife RefugeCameron County, best late November · 39 checklists that week, 2,059 in all83%
  2. Lower Rio Grande Valley National Wildlife Refuge (Brownsville Ship Channel)Cameron County, best late March · 24 checklists that week, 431 in all75%
  3. Fred Stone ParkWillacy County, best late November · 26 checklists that week, 314 in all74%
  4. Delta Lake ParkHidalgo County, best late November · 35 checklists that week, 896 in all72%
  5. Rollover IslandGalveston County, best late November · 23 checklists that week, 3,163 in all69%

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

Best time of day

In Texas, the Caspian Tern is most often listed on checklists started between 1 and 3 pm (2.6% of those checklists).

0%1%2%3%12 am: too few checklists (898) to judge1 am: too few checklists (756) to judge2 am: too few checklists (663) to judge3 am: too few checklists (741) to judge4 am: too few checklists (1537) to judge5 am: too few checklists (6113) to judge6 am: 2.0% of 74687 checklists7 am: 2.0% of 285131 checklists8 am: 2.4% of 329960 checklists9 am: 2.2% of 267889 checklists10 am: 2.4% of 218205 checklists11 am: 2.3% of 178879 checklists12 pm: 2.4% of 153722 checklists1 pm: 2.6% of 144662 checklists2 pm: 2.7% of 138578 checklists3 pm: 2.5% of 136878 checklists4 pm: 2.0% of 137550 checklists5 pm: 1.6% of 113599 checklists6 pm: 1.3% of 81743 checklists7 pm: 0.8% of 53396 checklists8 pm: too few checklists (17221) to judge9 pm: too few checklists (4048) to judge10 pm: too few checklists (1965) to judge11 pm: too few checklists (990) 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
January2.3%2.3%2.3%2.3%
February2.3%2.1%1.8%2.6%
March2.5%2.7%2.7%2.7%
April2.5%2.7%2.8%2.4%
May1.6%1.1%1.1%1.1%
June1.0%1.0%1.3%1.4%
July1.2%1.5%1.5%1.6%
August1.4%1.4%1.5%1.5%
September1.4%1.8%2.2%2.1%
October2.2%2.1%2.1%2.6%
November3.2%4.2%2.8%2.5%
December3.0%2.8%2.4%2.3%

Neighboring states

  • Louisiana: arrives early August, 6 weeks later than Texas
  • Mississippi: arrives mid March, 12 weeks earlier than Texas
  • Kansas: arrives early August, 6 weeks later than Texas
  • Alabama: arrives early March, 14 weeks earlier than Texas

Common questions

When do Caspian Terns arrive in Texas?
Caspian Terns are winter birds in Texas: the first arrive in mid June, they are common by the second week of September, peak in the second week of November (3.5% of checklists), and most are gone by early May.
When do Caspian Terns leave Texas?
Most Caspian Terns have left Texas by early May, when reports fall below half their usual rate. Stragglers are still reported until the second week of May.
When is the best time to see a Caspian Tern in Texas?
The Caspian Tern is reported most often in the second week of November, on about 3.5% of Texas checklists.
Where in Texas are Caspian Terns seen most often?
By county, Kleberg County, Kenedy County, and Starr County have the highest peak reporting rates for the Caspian Tern (counties with at least 200 checklists).