Northern Waterthrushes reach New Jersey in mid April, are common by late April, peak in the second week of May (6.8% of checklists), and most are gone by late May.
When to look
First arrivalsApr 15-21mid April
Common byApr 22-30late April
PeakMay 8-14the second week of May
Most gone byMay 22-31late May
Best: the second week of May. First arrivals mid April; most are gone by late May. Peak: on about 6.8% of New Jersey checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprcommon
Maypeak season
Jununcommon
Julrare
Augpeak season
Seppeak season
Octuncommon
Novnot usually seen
Decnot usually seen
Darker months: more checklists report it. Outlined: peak month.
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
0%few checklistsno data
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.
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In New Jersey, the Northern Waterthrush is most often listed on checklists started between 6 and 8 am (4.4% of those checklists).
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
Month
Days 1-7
8-14
15-21
22-end
January
0.1%
0%
0%
0%
February
0%
0%
0%
0%
March
0%
0%
0%
0%
April
0%
0.1%
0.2%
2.8%
May
6.9%
7.1%
6.3%
1.8%
June
0.4%
0.3%
0.3%
0.2%
July
0.1%
0.1%
0.1%
0.5%
August
1.7%
2.6%
3.4%
5.7%
September
6.3%
8.1%
5.7%
3.9%
October
1.9%
0.7%
0.2%
0.1%
November
0.1%
0%
0.1%
0%
December
0%
0%
0.1%
0.1%
Neighboring states
Delaware: arrives mid April, in the same week than New Jersey
Connecticut: arrives mid April, in the same week than New Jersey
Pennsylvania: arrives mid April, in the same week than New Jersey
New York: arrives mid April, in the same week than New Jersey
Common questions
When do Northern Waterthrushes arrive in New Jersey?
Northern Waterthrushes reach New Jersey in mid April, are common by late April, peak in the second week of May (6.8% of checklists), and most are gone by late May.
When do Northern Waterthrushes leave New Jersey?
Most Northern Waterthrushes have left New Jersey by late May, when reports fall below half their usual rate. Stragglers are still reported until early June.
When is the best time to see a Northern Waterthrush in New Jersey?
The Northern Waterthrush is reported most often in the second week of May, on about 6.8% of New Jersey checklists.
Where in New Jersey are Northern Waterthrushes seen most often?
By county, Cape May County, Passaic County, and Bergen County have the highest peak reporting rates for the Northern Waterthrush (counties with at least 200 checklists).