WhenToBird

Hydroprogne caspia · Laridae

When Do Caspian Terns Arrive in New Jersey?

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

Caspian Terns reach New Jersey in mid July, are common by late July, peak in late August (4.4% of checklists), and most are gone by mid October.

When to look

First arrivalsJul 15-21mid July
Common byJul 22-31late July
PeakAug 22-31late August
Most gone byOct 15-21mid October

Best: late August. First arrivals mid July; most are gone by mid October. Peak: on about 4.4% of New Jersey checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Apruncommon
  5. Mayuncommon
  6. Jununcommon
  7. Julcommon
  8. Augpeak season
  9. Seppeak season
  10. Octpeak season
  11. Novrare
  12. Decnot usually seen

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

0%2%4%6%Jan 1-7: 0% of 28167 checklistsJan 8-14: 0% of 20583 checklistsJan 15-21: 0% of 19739 checklistsJan 22-31: 0% of 24586 checklistsFeb 1-7: 0% of 17226 checklistsFeb 8-14: 0% of 19567 checklistsFeb 15-21: 0% of 26553 checklistsFeb 22-28: 0% of 19046 checklistsMar 1-7: 0% of 17969 checklistsMar 8-14: 0% of 18976 checklistsMar 15-21: 0% of 18581 checklistsMar 22-31: 0.1% of 27590 checklistsApr 1-7: 0.3% of 21202 checklistsApr 8-14: 0.6% of 23609 checklistsApr 15-21: 0.7% of 25056 checklistsApr 22-30: 0.7% of 36679 checklistsMay 1-7: 0.7% of 38378 checklistsMay 8-14: 0.7% of 44071 checklistsMay 15-21: 0.7% of 34076 checklistsMay 22-31: 0.7% of 32558 checklistsJun 1-7: 0.6% of 18049 checklistsJun 8-14: 0.6% of 15597 checklistsJun 15-21: 0.7% of 14894 checklistsJun 22-30: 0.7% of 17187 checklistsJul 1-7: 0.7% of 13406 checklistsJul 8-14: 1.0% of 12550 checklistsJul 15-21: 1.1% of 12358 checklistsJul 22-31: 2.1% of 18382 checklistsAug 1-7: 2.8% of 13689 checklistsAug 8-14: 3.4% of 14006 checklistsAug 15-21: 4.3% of 14483 checklistsAug 22-31: 4.7% of 23182 checklistsSep 1-7: 4.2% of 17984 checklistsSep 8-14: 3.9% of 18320 checklistsSep 15-21: 3.8% of 20491 checklistsSep 22-30: 4.0% of 26176 checklistsOct 1-7: 4.3% of 24112 checklistsOct 8-14: 3.4% of 24603 checklistsOct 15-21: 2.1% of 24549 checklistsOct 22-31: 0.7% of 26206 checklistsNov 1-7: 0.1% of 17469 checklistsNov 8-14: 0% of 15102 checklistsNov 15-21: 0% of 14958 checklistsNov 22-30: 0% of 19447 checklistsDec 1-7: 0% of 14017 checklistsDec 8-14: 0% of 14625 checklistsDec 15-21: 0% of 16937 checklistsDec 22-31: 0% of 26651 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 New Jersey 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 New Jersey

Best counties

Share of checklists at the peak
  1. Atlantic CountyBest late August · 733 checklists that week, 28,208 in all17%
  2. Cumberland CountyBest mid September · 162 checklists that week, 13,927 in all15%
  3. Gloucester CountyBest mid August · 513 checklists that week, 36,378 in all9.9%
  4. Camden CountyBest late August · 572 checklists that week, 25,931 in all8.6%
  5. Cape May CountyBest late September · 9174 checklists that week, 189,832 in all8.3%
  6. Salem CountyBest late September · 150 checklists that week, 9,658 in all6.8%

Best spots

Share of checklists at the peak
  1. Riverfront ParkGloucester County, best late August · 36 checklists that week, 1,033 in all95%
  2. Edwin B. Forsythe National Wildlife RefugeAtlantic County, best late August · 49 checklists that week, 1,233 in all73%
  3. Island Beach State Park (Sedge Islands)Ocean County, best late August · 34 checklists that week, 211 in all66%
  4. Norburys LandingCape May County, best late July · 20 checklists that week, 667 in all61%
  5. Pierces Point PondCape May County, best late August · 20 checklists that week, 363 in all60%

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

Best time of day

In New Jersey, the Caspian Tern is most often listed on checklists started between 6 and 8 am (1.5% of those checklists).

0%0.5%1%1.5%2%12 am: too few checklists (746) to judge1 am: too few checklists (640) to judge2 am: too few checklists (606) to judge3 am: too few checklists (755) to judge4 am: too few checklists (1681) to judge5 am: too few checklists (11258) to judge6 am: 2.0% of 50447 checklists7 am: 1.2% of 118312 checklists8 am: 1.1% of 123273 checklists9 am: 1.0% of 107783 checklists10 am: 1.0% of 97537 checklists11 am: 0.9% of 82427 checklists12 pm: 0.9% of 72581 checklists1 pm: 1.0% of 71478 checklists2 pm: 1.0% of 69994 checklists3 pm: 1.1% of 66822 checklists4 pm: 1.2% of 55950 checklists5 pm: 1.4% of 41360 checklists6 pm: 1.1% of 28122 checklists7 pm: too few checklists (14727) to judge8 pm: too few checklists (4257) to judge9 pm: too few checklists (1273) to judge10 pm: too few checklists (920) to judge11 pm: too few checklists (693) 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%0.1%
April0.3%0.6%0.7%0.7%
May0.7%0.7%0.7%0.7%
June0.6%0.6%0.7%0.7%
July0.7%1.0%1.1%2.1%
August2.8%3.4%4.3%4.7%
September4.2%3.9%3.8%4.0%
October4.3%3.4%2.1%0.7%
November0.1%0%0%0%
December0%0%0%0%

Neighboring states

  • Delaware: arrives early April, 14 weeks earlier than New Jersey
  • Pennsylvania: arrives the second week of July, 1 week earlier than New Jersey
  • New York: arrives the second week of April, 13 weeks earlier than New Jersey
  • Maryland: arrives mid July, in the same week than New Jersey

Common questions

When do Caspian Terns arrive in New Jersey?
Caspian Terns reach New Jersey in mid July, are common by late July, peak in late August (4.4% of checklists), and most are gone by mid October.
When do Caspian Terns leave New Jersey?
Most Caspian Terns have left New Jersey by mid October, when reports fall below half their usual rate. Stragglers are still reported until late October.
When is the best time to see a Caspian Tern in New Jersey?
The Caspian Tern is reported most often in late August, on about 4.4% of New Jersey checklists.
Where in New Jersey are Caspian Terns seen most often?
By county, Atlantic County, Cumberland County, and Gloucester County have the highest peak reporting rates for the Caspian Tern (counties with at least 200 checklists).