WhenToBird

Circus hudsonius · Accipitridae

When Do Northern Harriers Arrive in New York?

Northern Harriers are winter birds in New York: the first arrive in mid August, they are common by late August, peak in the second week of November (4.5% of checklists), and most are gone by early May.

When to look

First arrivalsAug 15-21mid August
Common byAug 22-31late August
PeakNov 8-14the second week of November
Most gone byMay 1-7early May

Best: the second week of November. First arrivals mid August; most are gone by early May. Peak: on about 4.5% of New York checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marcommon
  4. Aprpeak season
  5. Maycommon
  6. Junrare
  7. Julrare
  8. Augcommon
  9. Seppeak season
  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: 3.7% of 66410 checklistsJan 8-14: 3.9% of 49310 checklistsJan 15-21: 3.7% of 49919 checklistsJan 22-31: 3.8% of 62513 checklistsFeb 1-7: 3.5% of 43526 checklistsFeb 8-14: 3.2% of 49753 checklistsFeb 15-21: 2.6% of 65147 checklistsFeb 22-28: 3.2% of 50173 checklistsMar 1-7: 3.0% of 50325 checklistsMar 8-14: 3.0% of 55371 checklistsMar 15-21: 3.2% of 56293 checklistsMar 22-31: 3.2% of 82677 checklistsApr 1-7: 3.6% of 65295 checklistsApr 8-14: 3.7% of 73080 checklistsApr 15-21: 3.1% of 73857 checklistsApr 22-30: 2.5% of 106093 checklistsMay 1-7: 1.7% of 102772 checklistsMay 8-14: 1.2% of 110051 checklistsMay 15-21: 1.0% of 94797 checklistsMay 22-31: 0.7% of 101272 checklistsJun 1-7: 0.5% of 59471 checklistsJun 8-14: 0.5% of 55497 checklistsJun 15-21: 0.4% of 51761 checklistsJun 22-30: 0.4% of 59219 checklistsJul 1-7: 0.5% of 48226 checklistsJul 8-14: 0.6% of 42315 checklistsJul 15-21: 0.5% of 40637 checklistsJul 22-31: 0.6% of 57183 checklistsAug 1-7: 0.6% of 40461 checklistsAug 8-14: 1.0% of 39880 checklistsAug 15-21: 1.2% of 41146 checklistsAug 22-31: 2.0% of 63381 checklistsSep 1-7: 2.5% of 48640 checklistsSep 8-14: 2.6% of 47882 checklistsSep 15-21: 3.3% of 49063 checklistsSep 22-30: 3.8% of 57906 checklistsOct 1-7: 4.3% of 48447 checklistsOct 8-14: 4.2% of 51901 checklistsOct 15-21: 4.5% of 46717 checklistsOct 22-31: 4.4% of 61992 checklistsNov 1-7: 4.4% of 44593 checklistsNov 8-14: 4.5% of 42566 checklistsNov 15-21: 4.6% of 39675 checklistsNov 22-30: 4.0% of 51197 checklistsDec 1-7: 3.8% of 36567 checklistsDec 8-14: 3.7% of 37254 checklistsDec 15-21: 3.2% of 43754 checklistsDec 22-31: 3.7% of 62470 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 York 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 York

Best counties

Share of checklists at the peak
  1. Seneca CountyBest the second week of October · 884 checklists that week, 47,387 in all35%
  2. Ulster CountyBest early February · 1076 checklists that week, 71,816 in all18%
  3. Washington CountyBest the second week of December · 187 checklists that week, 15,060 in all17%
  4. Wayne CountyBest the second week of April · 1077 checklists that week, 37,738 in all16%
  5. Oswego CountyBest mid April · 1120 checklists that week, 39,208 in all13%
  6. Nassau CountyBest the second week of November · 1835 checklists that week, 95,019 in all13%

Best spots

Share of checklists at the peak
  1. Shawangunk Grasslands National Wildlife RefugeUlster County, best mid January · 157 checklists that week, 5,492 in all95%
  2. Town of Shawangunk Land (Galeville)Ulster County, best late January · 22 checklists that week, 518 in all84%
  3. Wallkill River National Wildlife Refuge (north)Orange County, best late January · 20 checklists that week, 875 in all82%
  4. Wallkill River National Wildlife RefugeOrange County, best mid January · 39 checklists that week, 3,135 in all81%
  5. Black Lake (east)Seneca County, best late November · 30 checklists that week, 798 in all80%

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

Best time of day

In New York, the Northern Harrier is most often listed on checklists started between 2 and 4 pm (3.3% of those checklists).

0%1%2%3%4%12 am: too few checklists (1146) to judge1 am: too few checklists (1055) to judge2 am: too few checklists (1121) to judge3 am: too few checklists (1353) to judge4 am: too few checklists (4785) to judge5 am: too few checklists (32052) to judge6 am: 1.8% of 124869 checklists7 am: 2.0% of 298506 checklists8 am: 2.3% of 337334 checklists9 am: 2.7% of 307787 checklists10 am: 2.9% of 270801 checklists11 am: 2.9% of 233238 checklists12 pm: 2.8% of 213830 checklists1 pm: 3.0% of 193321 checklists2 pm: 3.2% of 180741 checklists3 pm: 3.5% of 170348 checklists4 pm: 3.2% of 147224 checklists5 pm: 2.0% of 111962 checklists6 pm: 1.5% of 78261 checklists7 pm: too few checklists (44425) to judge8 pm: too few checklists (15648) to judge9 pm: too few checklists (4795) to judge10 pm: too few checklists (2454) to judge11 pm: too few checklists (1378) 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
January3.7%3.9%3.7%3.8%
February3.5%3.2%2.6%3.2%
March3.0%3.0%3.2%3.2%
April3.6%3.7%3.1%2.5%
May1.7%1.2%1.0%0.7%
June0.5%0.5%0.4%0.4%
July0.5%0.6%0.5%0.6%
August0.6%1.0%1.2%2.0%
September2.5%2.6%3.3%3.8%
October4.3%4.2%4.5%4.4%
November4.4%4.5%4.6%4.0%
December3.8%3.7%3.2%3.7%

Neighboring states

  • Connecticut: arrives mid August, in the same week than New York
  • New Jersey: arrives late August, 1 week later than New York
  • Pennsylvania: arrives the second week of September, 3 weeks later than New York
  • Vermont: arrives early August, 2 weeks earlier than New York

Common questions

When do Northern Harriers arrive in New York?
Northern Harriers are winter birds in New York: the first arrive in mid August, they are common by late August, peak in the second week of November (4.5% of checklists), and most are gone by early May.
When do Northern Harriers leave New York?
Most Northern Harriers have left New York 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 Northern Harrier in New York?
The Northern Harrier is reported most often in the second week of November, on about 4.5% of New York checklists.
Where in New York are Northern Harriers seen most often?
By county, Seneca County, Ulster County, and Washington County have the highest peak reporting rates for the Northern Harrier (counties with at least 200 checklists).