Black-and-white Warblers mostly pass through Massachusetts: the first show up in mid April, they are common by late April, peak in the second week of May (28% 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 28% of Massachusetts checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprcommon
Maypeak season
Jununcommon
Julrare
Augrare
Sepuncommon
Octrare
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 Massachusetts 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.
J.A. Skinner State ParkHampshire County, best the second week of May · 243 checklists that week, 1,818 in all90%
Wade PondHampden County, best the second week of May · 52 checklists that week, 516 in all89%
Larence SwampHampshire County, best the second week of May · 64 checklists that week, 843 in all87%
Quabbin Reservoir WatershedHampshire County, best the second week of May · 106 checklists that week, 1,878 in all86%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Massachusetts, the Black-and-white Warbler is most often listed on checklists started between 6 and 8 am (9.4% 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
0.1%
0.1%
0.5%
8.4%
May
27%
31%
27%
12%
June
7.3%
6.6%
6.1%
4.5%
July
3.3%
2.5%
2.2%
2.2%
August
2.6%
3.0%
3.0%
3.9%
September
4.0%
5.8%
6.4%
6.0%
October
3.0%
1.0%
0.3%
0.1%
November
0.1%
0.1%
0.1%
0.1%
December
0.1%
0.1%
0.1%
0.1%
Neighboring states
Rhode Island: arrives mid April, in the same week than Massachusetts
New Hampshire: arrives mid April, in the same week than Massachusetts
Connecticut: arrives mid April, in the same week than Massachusetts
Vermont: arrives mid April, in the same week than Massachusetts
Common questions
When do Black-and-white Warblers arrive in Massachusetts?
Black-and-white Warblers mostly pass through Massachusetts: the first show up in mid April, they are common by late April, peak in the second week of May (28% of checklists), and most are gone by late May.
When do Black-and-white Warblers leave Massachusetts?
Most Black-and-white Warblers have left Massachusetts by late May, when reports fall below half their usual rate. Stragglers are still reported until early October.
When is the best time to see a Black-and-white Warbler in Massachusetts?
The Black-and-white Warbler is reported most often in the second week of May, on about 28% of Massachusetts checklists.
Where in Massachusetts are Black-and-white Warblers seen most often?
By county, Franklin County, Suffolk County, and Hampshire County have the highest peak reporting rates for the Black-and-white Warbler (counties with at least 200 checklists).
