Broad-tailed Hummingbirds reach Colorado in mid April, are common by early May, peak in late July (41% of checklists), and most are gone by the second week of September.
When to look
First arrivalsApr 15-21mid April
Common byMay 1-7early May
PeakJul 22-31late July
Most gone bySep 8-14the second week of September
Best: late July. First arrivals mid April; most are gone by the second week of September. Peak: on about 41% of Colorado checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Apruncommon
Maypeak season
Junpeak season
Julpeak season
Augpeak season
Sepcommon
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 Colorado 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.
State Forest State ParkJackson County, best late June · 31 checklists that week, 748 in all95%
Kohler ReservoirBoulder County, best the second week of May · 81 checklists that week, 1,037 in all95%
Lair o' the Bear ParkJefferson County, best mid June · 51 checklists that week, 1,259 in all95%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Colorado, the Broad-tailed Hummingbird is most often listed on checklists started between 6 and 8 am (24% 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%
0.1%
0.1%
April
0.1%
0.9%
2.7%
8.9%
May
17%
24%
30%
33%
June
31%
32%
32%
33%
July
35%
38%
40%
41%
August
41%
39%
35%
30%
September
23%
17%
12%
6.3%
October
2.6%
1.0%
0.3%
0.1%
November
0.1%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Wyoming: arrives early May, 2 weeks later than Colorado
New Mexico: arrives early April, 2 weeks earlier than Colorado
Utah: arrives the second week of April, 1 week earlier than Colorado
Arizona: arrives the second week of March, 5 weeks earlier than Colorado
Common questions
When do Broad-tailed Hummingbirds arrive in Colorado?
Broad-tailed Hummingbirds reach Colorado in mid April, are common by early May, peak in late July (41% of checklists), and most are gone by the second week of September.
When do Broad-tailed Hummingbirds leave Colorado?
Most Broad-tailed Hummingbirds have left Colorado by the second week of September, when reports fall below half their usual rate. Stragglers are still reported until early October.
When is the best time to see a Broad-tailed Hummingbird in Colorado?
The Broad-tailed Hummingbird is reported most often in late July, on about 41% of Colorado checklists.
Where in Colorado are Broad-tailed Hummingbirds seen most often?
By county, Gilpin County, Pitkin County, and Douglas County have the highest peak reporting rates for the Broad-tailed Hummingbird (counties with at least 200 checklists).