Red-winged Blackbirds are in Massachusetts all year, but most are here in spring: numbers build from early March, peak in early May (61% of checklists), and fall back by late July. In the quietest week (mid January) they are still on about 3.7% of checklists.
When to look
Numbers buildMar 1-7early March
PeakMay 1-7early May
Fall back byJul 22-31late July
FewestJan 15-21mid January
Best: early May. Here all year; numbers build from early March and fall back by late July. Peak: on about 61% of Massachusetts checklists.
Janrare
Febuncommon
Marpeak season
Aprpeak season
Maypeak season
Junpeak season
Julpeak season
Augcommon
Seprare
Octuncommon
Novuncommon
Decrare
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.
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Massachusetts, the Red-winged Blackbird is most often listed on checklists started between 6 and 8 am (40% 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
4.0%
3.9%
3.3%
3.8%
February
4.7%
8.5%
14%
25%
March
35%
43%
47%
49%
April
51%
54%
57%
61%
May
63%
60%
59%
57%
June
56%
55%
53%
52%
July
49%
46%
42%
35%
August
28%
20%
14%
11%
September
8.2%
6.8%
6.3%
7.6%
October
11%
14%
17%
16%
November
13%
10%
7.8%
5.8%
December
4.5%
4.6%
4.9%
4.5%
Neighboring states
Rhode Island: arrives the second week of February, 3 weeks earlier than Massachusetts
New Hampshire: arrives mid February, 2 weeks earlier than Massachusetts
Connecticut: arrives early March, in the same week than Massachusetts
Vermont: arrives mid February, 2 weeks earlier than Massachusetts
Common questions
When do Red-winged Blackbirds arrive in Massachusetts?
Red-winged Blackbirds are in Massachusetts all year, but most are here in spring: numbers build from early March, peak in early May (61% of checklists), and fall back by late July. In the quietest week (mid January) they are still on about 3.7% of checklists.
When do Red-winged Blackbirds leave Massachusetts?
Red-winged Blackbirds never fully leave Massachusetts: numbers fall back below half their usual rate by late July, but some are still reported in every week, about 3.7% of checklists at the low.
When is the best time to see a Red-winged Blackbird in Massachusetts?
The Red-winged Blackbird is reported most often in early May, on about 61% of Massachusetts checklists.
Where in Massachusetts are Red-winged Blackbirds seen most often?
By county, Middlesex County, Essex County, and Nantucket County have the highest peak reporting rates for the Red-winged Blackbird (counties with at least 200 checklists).