Olive-sided Flycatchers arrive in Missouri in mid August, peak in the second week of September (1.7% of checklists), and most are gone by late September.
When to look
First arrivalsAug 15-21mid August
Common byAug 15-21mid August
PeakSep 8-14the second week of September
Most gone bySep 22-30late September
Best: the second week of September. First arrivals mid August; most are gone by late September. Peak: on about 1.7% of Missouri checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprrare
Maypeak season
Juncommon
Julnot usually seen
Augpeak season
Seppeak season
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 Missouri 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.
Tower Grove ParkSt. Louis City, best late May · 290 checklists that week, 6,087 in all12%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Missouri, the Olive-sided Flycatcher is most often listed on checklists started between 6 and 8 am (0.5% 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%
0%
0%
0%
February
0%
0%
0%
0%
March
0%
0%
0%
0%
April
0%
0%
0%
0.1%
May
0.6%
1.3%
2.3%
1.5%
June
0.2%
0.1%
0%
0%
July
0%
0%
0%
0%
August
0.1%
0.4%
0.6%
1.0%
September
2.2%
1.9%
1.0%
0.5%
October
0.1%
0.1%
0%
0%
November
0%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Iowa: arrives the second week of August, 1 week earlier than Missouri
Kansas: arrives the second week of August, 1 week earlier than Missouri
Illinois: arrives the second week of May, 13 weeks earlier than Missouri
Indiana: arrives the second week of August, 1 week earlier than Missouri
Common questions
When do Olive-sided Flycatchers arrive in Missouri?
Olive-sided Flycatchers arrive in Missouri in mid August, peak in the second week of September (1.7% of checklists), and most are gone by late September.
When do Olive-sided Flycatchers leave Missouri?
Most Olive-sided Flycatchers have left Missouri by late September, when reports fall below half their usual rate.
When is the best time to see a Olive-sided Flycatcher in Missouri?
The Olive-sided Flycatcher is reported most often in the second week of September, on about 1.7% of Missouri checklists.
Where in Missouri are Olive-sided Flycatchers seen most often?
By county, Barton County, Andrew County, and Dunklin County have the highest peak reporting rates for the Olive-sided Flycatcher (counties with at least 200 checklists).