WhenToBird

Aythya affinis · Anatidae

When Do Lesser Scaups Arrive in New Jersey?

Adult male Lesser Scaup
Photo: Paul Lewis, CC BY 4.0 via iNaturalist

Lesser Scaups are winter birds in New Jersey: the first arrive in late October, they are common by early November, peak in early March (4.2% of checklists), and most are gone by early April.

When to look

First arrivalsOct 22-31late October
Common byNov 1-7early November
PeakMar 1-7early March
Most gone byApr 1-7early April

Best: early March. First arrivals late October; most are gone by early April. Peak: on about 4.2% of New Jersey checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marpeak season
  4. Aprcommon
  5. Maynot usually seen
  6. Junnot usually seen
  7. Julnot usually seen
  8. Augnot usually seen
  9. Sepnot usually seen
  10. Octuncommon
  11. Novpeak season
  12. Decpeak season

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

0%2%4%6%Jan 1-7: 4.1% of 28167 checklistsJan 8-14: 3.8% of 20583 checklistsJan 15-21: 3.6% of 19739 checklistsJan 22-31: 3.6% of 24586 checklistsFeb 1-7: 3.8% of 17226 checklistsFeb 8-14: 3.4% of 19567 checklistsFeb 15-21: 3.3% of 26553 checklistsFeb 22-28: 4.8% of 19046 checklistsMar 1-7: 4.4% of 17969 checklistsMar 8-14: 3.4% of 18976 checklistsMar 15-21: 3.0% of 18581 checklistsMar 22-31: 2.2% of 27590 checklistsApr 1-7: 2.2% of 21202 checklistsApr 8-14: 1.4% of 23609 checklistsApr 15-21: 1.0% of 25056 checklistsApr 22-30: 0.3% of 36679 checklistsMay 1-7: 0.1% of 38378 checklistsMay 8-14: 0.1% of 44071 checklistsMay 15-21: 0.1% of 34076 checklistsMay 22-31: 0.1% of 32558 checklistsJun 1-7: 0.1% of 18049 checklistsJun 8-14: 0.1% of 15597 checklistsJun 15-21: 0.1% of 14894 checklistsJun 22-30: 0.1% of 17187 checklistsJul 1-7: 0.1% of 13406 checklistsJul 8-14: 0.1% of 12550 checklistsJul 15-21: 0.1% of 12358 checklistsJul 22-31: 0.1% of 18382 checklistsAug 1-7: 0.1% of 13689 checklistsAug 8-14: 0.1% of 14006 checklistsAug 15-21: 0.1% of 14483 checklistsAug 22-31: 0.1% of 23182 checklistsSep 1-7: 0% of 17984 checklistsSep 8-14: 0.1% of 18320 checklistsSep 15-21: 0% of 20491 checklistsSep 22-30: 0.1% of 26176 checklistsOct 1-7: 0.1% of 24112 checklistsOct 8-14: 0.1% of 24603 checklistsOct 15-21: 0.5% of 24549 checklistsOct 22-31: 1.2% of 26206 checklistsNov 1-7: 2.1% of 17469 checklistsNov 8-14: 2.6% of 15102 checklistsNov 15-21: 3.0% of 14958 checklistsNov 22-30: 3.1% of 19447 checklistsDec 1-7: 3.4% of 14017 checklistsDec 8-14: 2.7% of 14625 checklistsDec 15-21: 2.3% of 16937 checklistsDec 22-31: 2.7% 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. Hunterdon CountyBest mid November · 1028 checklists that week, 57,610 in all13%
  2. Ocean CountyBest late February · 2047 checklists that week, 87,340 in all9.0%
  3. Warren CountyBest early March · 505 checklists that week, 20,077 in all6.5%
  4. Hudson CountyBest late January · 477 checklists that week, 21,191 in all6.3%
  5. Cumberland CountyBest mid February · 398 checklists that week, 13,927 in all6.1%
  6. Monmouth CountyBest the second week of January · 2064 checklists that week, 79,748 in all6.1%

Best spots

Share of checklists at the peak
  1. Lake of the LilliesOcean County, best mid March · 74 checklists that week, 2,803 in all84%
  2. Round Valley Recreation AreaHunterdon County, best early December · 110 checklists that week, 3,877 in all79%
  3. North BasinCape May County, best the second week of February · 25 checklists that week, 129 in all62%
  4. BivalveCumberland County, best mid February · 21 checklists that week, 235 in all57%
  5. Manasquan ReservoirMonmouth County, best the second week of January · 40 checklists that week, 1,468 in all53%

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

Best time of day

In New Jersey, the Lesser Scaup is most often listed on checklists started between 1 and 3 pm (2.0% 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: 1.0% of 50447 checklists7 am: 1.2% of 118312 checklists8 am: 1.3% of 123273 checklists9 am: 1.6% of 107783 checklists10 am: 1.7% of 97537 checklists11 am: 1.8% of 82427 checklists12 pm: 1.9% of 72581 checklists1 pm: 2.0% of 71478 checklists2 pm: 1.9% of 69994 checklists3 pm: 1.8% of 66822 checklists4 pm: 1.3% of 55950 checklists5 pm: 0.5% of 41360 checklists6 pm: 0.2% 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
January4.1%3.8%3.6%3.6%
February3.8%3.4%3.3%4.8%
March4.4%3.4%3.0%2.2%
April2.2%1.4%1.0%0.3%
May0.1%0.1%0.1%0.1%
June0.1%0.1%0.1%0.1%
July0.1%0.1%0.1%0.1%
August0.1%0.1%0.1%0.1%
September0%0.1%0%0.1%
October0.1%0.1%0.5%1.2%
November2.1%2.6%3.0%3.1%
December3.4%2.7%2.3%2.7%

Neighboring states

  • Delaware: arrives early November, 1 week later than New Jersey
  • Connecticut: arrives the second week of November, 2 weeks later than New Jersey
  • Pennsylvania: arrives early November, 1 week later than New Jersey
  • New York: arrives mid October, 1 week earlier than New Jersey

Common questions

When do Lesser Scaups arrive in New Jersey?
Lesser Scaups are winter birds in New Jersey: the first arrive in late October, they are common by early November, peak in early March (4.2% of checklists), and most are gone by early April.
When do Lesser Scaups leave New Jersey?
Most Lesser Scaups have left New Jersey by early April, when reports fall below half their usual rate. Stragglers are still reported until the second week of April.
When is the best time to see a Lesser Scaup in New Jersey?
The Lesser Scaup is reported most often in early March, on about 4.2% of New Jersey checklists.
Where in New Jersey are Lesser Scaups seen most often?
By county, Hunterdon County, Ocean County, and Warren County have the highest peak reporting rates for the Lesser Scaup (counties with at least 200 checklists).