Palm Warblers are winter birds in Maryland: they arrive in early September, peak in the second week of October (14% of checklists), and most are gone by early January.
When to look
First arrivalsSep 1-7early September
Common bySep 1-7early September
PeakOct 8-14the second week of October
Most gone byJan 1-7early January
Best: the second week of October. First arrivals early September; most are gone by early January. Peak: on about 14% of Maryland checklists.
Jannot usually seen
Febnot usually seen
Maruncommon
Aprcommon
Mayuncommon
Junnot usually seen
Julnot usually seen
Augnot usually seen
Sepcommon
Octpeak season
Novuncommon
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 Maryland 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.
Harford CountyBest the second week of October · 580 checklists that week, 39,311 in all27%
Cecil CountyBest the second week of October · 284 checklists that week, 18,620 in all24%
Queen Anne's CountyBest mid October · 395 checklists that week, 26,875 in all22%
Baltimore CountyBest the second week of October · 2588 checklists that week, 136,139 in all21%
Howard CountyBest the second week of October · 1787 checklists that week, 118,290 in all19%
Garrett CountyBest early October · 439 checklists that week, 37,616 in all19%
Best spots
Share of checklists at the peak
Perryman ParkHarford County, best mid October · 59 checklists that week, 849 in all89%
Trout RunGarrett County, best late September · 56 checklists that week, 1,215 in all84%
Swan Harbor FarmHarford County, best the second week of October · 61 checklists that week, 4,020 in all81%
Oregon Pool (Greencroft)Baltimore County, best the second week of October · 36 checklists that week, 1,058 in all80%
Turkey PointCecil County, best mid October · 35 checklists that week, 976 in all73%
Crabbs Branch SvpMontgomery County, best the second week of October · 27 checklists that week, 484 in all72%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Maryland, the Palm Warbler is most often listed on checklists started between 6 and 8 am (3.7% 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
0.2%
0.2%
0.1%
0.1%
February
0.1%
0.1%
0.1%
0.2%
March
0.1%
0.1%
0.1%
1.3%
April
7.2%
11%
8.6%
6.2%
May
3.0%
1.1%
0.1%
0.1%
June
0%
0%
0%
0%
July
0%
0%
0%
0%
August
0%
0.1%
0%
0.1%
September
0.2%
1.6%
5.0%
7.7%
October
13%
15%
15%
9.7%
November
3.7%
2.4%
0.6%
0.5%
December
0.4%
0.3%
0.3%
0.5%
Neighboring states
District of Columbia: arrives the second week of September, 1 week later than Maryland
Delaware: arrives early September, in the same week than Maryland
Virginia: arrives early September, in the same week than Maryland
Pennsylvania: arrives early September, in the same week than Maryland
Common questions
When do Palm Warblers arrive in Maryland?
Palm Warblers are winter birds in Maryland: they arrive in early September, peak in the second week of October (14% of checklists), and most are gone by early January.
When do Palm Warblers leave Maryland?
Most Palm Warblers have left Maryland by early January, when reports fall below half their usual rate.
When is the best time to see a Palm Warbler in Maryland?
The Palm Warbler is reported most often in the second week of October, on about 14% of Maryland checklists.
Where in Maryland are Palm Warblers seen most often?
By county, Harford County, Cecil County, and Queen Anne's County have the highest peak reporting rates for the Palm Warbler (counties with at least 200 checklists).