WhenToBird

Astur cooperii · Accipitridae

When Do Cooper's Hawks Arrive in New Jersey?

Adult male Cooper's Hawk
Photo: Shirley Zundell, CC BY 4.0 via iNaturalist

Cooper's Hawks are in New Jersey all year, but most are here in fall: numbers build from mid September, peak in the second week of October (23% of checklists), and fall back by the second week of November. In the quietest week (mid July) they are still on about 2.4% of checklists.

When to look

Numbers buildSep 15-21mid September
PeakOct 8-14the second week of October
Fall back byNov 8-14the second week of November
FewestJul 15-21mid July

Best: the second week of October. Here all year; numbers build from mid September and fall back by the second week of November. Peak: on about 23% of New Jersey checklists.

  1. Januncommon
  2. Febuncommon
  3. Maruncommon
  4. Apruncommon
  5. Mayuncommon
  6. Junrare
  7. Julrare
  8. Auguncommon
  9. Seppeak season
  10. Octpeak season
  11. Novcommon
  12. Deccommon

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

0%10%20%30%Jan 1-7: 5.9% of 28167 checklistsJan 8-14: 6.2% of 20583 checklistsJan 15-21: 5.6% of 19739 checklistsJan 22-31: 5.6% of 24586 checklistsFeb 1-7: 5.3% of 17226 checklistsFeb 8-14: 4.6% of 19567 checklistsFeb 15-21: 4.5% of 26553 checklistsFeb 22-28: 4.5% of 19046 checklistsMar 1-7: 4.7% of 17969 checklistsMar 8-14: 5.2% of 18976 checklistsMar 15-21: 5.1% of 18581 checklistsMar 22-31: 5.2% of 27590 checklistsApr 1-7: 5.6% of 21202 checklistsApr 8-14: 5.5% of 23609 checklistsApr 15-21: 5.6% of 25056 checklistsApr 22-30: 5.0% of 36679 checklistsMay 1-7: 4.2% of 38378 checklistsMay 8-14: 3.1% of 44071 checklistsMay 15-21: 2.8% of 34076 checklistsMay 22-31: 2.4% of 32558 checklistsJun 1-7: 2.6% of 18049 checklistsJun 8-14: 3.0% of 15597 checklistsJun 15-21: 2.9% of 14894 checklistsJun 22-30: 2.6% of 17187 checklistsJul 1-7: 2.7% of 13406 checklistsJul 8-14: 2.3% of 12550 checklistsJul 15-21: 2.2% of 12358 checklistsJul 22-31: 2.6% of 18382 checklistsAug 1-7: 3.5% of 13689 checklistsAug 8-14: 4.4% of 14006 checklistsAug 15-21: 5.7% of 14483 checklistsAug 22-31: 6.7% of 23182 checklistsSep 1-7: 8.2% of 17984 checklistsSep 8-14: 9.9% of 18320 checklistsSep 15-21: 15% of 20491 checklistsSep 22-30: 18% of 26176 checklistsOct 1-7: 21% of 24112 checklistsOct 8-14: 24% of 24603 checklistsOct 15-21: 25% of 24549 checklistsOct 22-31: 19% of 26206 checklistsNov 1-7: 14% of 17469 checklistsNov 8-14: 13% of 15102 checklistsNov 15-21: 12% of 14958 checklistsNov 22-30: 10% of 19447 checklistsDec 1-7: 9.5% of 14017 checklistsDec 8-14: 8.4% of 14625 checklistsDec 15-21: 8.3% of 16937 checklistsDec 22-31: 6.8% 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. Cape May CountyBest mid October · 10065 checklists that week, 189,832 in all39%
  2. Somerset CountyBest mid October · 1098 checklists that week, 58,057 in all18%
  3. Bergen CountyBest mid October · 1471 checklists that week, 73,457 in all17%
  4. Burlington CountyBest mid October · 911 checklists that week, 52,358 in all17%
  5. Hunterdon CountyBest late September · 1208 checklists that week, 57,610 in all16%
  6. Monmouth CountyBest the second week of October · 1337 checklists that week, 79,748 in all15%

Best spots

Share of checklists at the peak
  1. Cape May County Park SouthCape May County, best the second week of October · 30 checklists that week, 337 in all78%
  2. Higbee Beach Wildlife Management Area (north)Cape May County, best mid October · 114 checklists that week, 1,492 in all71%
  3. Higbee Beach Wildlife Management Area (Lake Lily)Cape May County, best mid October · 53 checklists that week, 781 in all68%
  4. Washington Valley ParkSomerset County, best late October · 48 checklists that week, 1,255 in all67%
  5. Cape May Point State Park (southwest)Cape May County, best the second week of October · 1158 checklists that week, 9,860 in all66%

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

Best time of day

In New Jersey, the Cooper's Hawk is most often listed on checklists started between 6 and 8 am (10% of those checklists).

0%5%10%15%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: 9.5% of 50447 checklists7 am: 11% of 118312 checklists8 am: 8.7% of 123273 checklists9 am: 8.7% of 107783 checklists10 am: 8.6% of 97537 checklists11 am: 7.5% of 82427 checklists12 pm: 6.9% of 72581 checklists1 pm: 6.8% of 71478 checklists2 pm: 6.6% of 69994 checklists3 pm: 6.2% of 66822 checklists4 pm: 5.2% of 55950 checklists5 pm: 4.4% of 41360 checklists6 pm: 3.2% 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
January5.9%6.2%5.6%5.6%
February5.3%4.6%4.5%4.5%
March4.7%5.2%5.1%5.2%
April5.6%5.5%5.6%5.0%
May4.2%3.1%2.8%2.4%
June2.6%3.0%2.9%2.6%
July2.7%2.3%2.2%2.6%
August3.5%4.4%5.7%6.7%
September8.2%9.9%15%18%
October21%24%25%19%
November14%13%12%10%
December9.5%8.4%8.3%6.8%

Neighboring states

  • Delaware: arrives early September, 2 weeks earlier than New Jersey
  • Connecticut: arrives late July, 7 weeks earlier than New Jersey
  • Pennsylvania: arrives the second week of September, 1 week earlier than New Jersey
  • New York: arrives mid July, 8 weeks earlier than New Jersey

Common questions

When do Cooper's Hawks arrive in New Jersey?
Cooper's Hawks are in New Jersey all year, but most are here in fall: numbers build from mid September, peak in the second week of October (23% of checklists), and fall back by the second week of November. In the quietest week (mid July) they are still on about 2.4% of checklists.
When do Cooper's Hawks leave New Jersey?
Cooper's Hawks never fully leave New Jersey: numbers fall back below half their usual rate by the second week of November, but some are still reported in every week, about 2.4% of checklists at the low.
When is the best time to see a Cooper's Hawk in New Jersey?
The Cooper's Hawk is reported most often in the second week of October, on about 23% of New Jersey checklists.
Where in New Jersey are Cooper's Hawks seen most often?
By county, Cape May County, Somerset County, and Bergen County have the highest peak reporting rates for the Cooper's Hawk (counties with at least 200 checklists).