WhenToBird

Empidonax alnorum · Tyrannidae

Alder Flycatcher: When and Where to See It

Adult Alder Flycatcher
Photo: Brandon Johnson, CC BY 4.0 via iNaturalist

The Alder Flycatcher reaches Vermont first, around the second week of May, and Alaska last, around late May.

JanFebMarAprMayJunJulAugSepOctNovDec
today
Second week of November

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.

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0%1%2%3%Jan 1-7: 0% of 1114036 checklistsJan 8-14: 0% of 824708 checklistsJan 15-21: 0% of 825978 checklistsJan 22-31: 0% of 1105853 checklistsFeb 1-7: 0% of 779772 checklistsFeb 8-14: 0% of 864504 checklistsFeb 15-21: 0% of 1127933 checklistsFeb 22-28: 0% of 840124 checklistsMar 1-7: 0% of 839610 checklistsMar 8-14: 0% of 870138 checklistsMar 15-21: 0% of 898456 checklistsMar 22-31: 0% of 1335637 checklistsApr 1-7: 0.1% of 1030617 checklistsApr 8-14: 0% of 1124024 checklistsApr 15-21: 0.1% of 1194575 checklistsApr 22-30: 0.1% of 1675723 checklistsMay 1-7: 0.1% of 1449080 checklistsMay 8-14: 0.3% of 1538353 checklistsMay 15-21: 1.5% of 1219898 checklistsMay 22-31: 3.0% of 1452282 checklistsJun 1-7: 2.6% of 900636 checklistsJun 8-14: 2.1% of 829907 checklistsJun 15-21: 1.8% of 773255 checklistsJun 22-30: 1.1% of 916255 checklistsJul 1-7: 0.7% of 717733 checklistsJul 8-14: 0.6% of 658223 checklistsJul 15-21: 0.8% of 638752 checklistsJul 22-31: 0.9% of 895727 checklistsAug 1-7: 0.7% of 655651 checklistsAug 8-14: 0.4% of 650038 checklistsAug 15-21: 0.3% of 654639 checklistsAug 22-31: 0.2% of 974928 checklistsSep 1-7: 0.2% of 765914 checklistsSep 8-14: 0.1% of 738674 checklistsSep 15-21: 0.1% of 750433 checklistsSep 22-30: 0.1% of 944196 checklistsOct 1-7: 0.1% of 760106 checklistsOct 8-14: 0.1% of 793131 checklistsOct 15-21: 0.1% of 728727 checklistsOct 22-31: 0.1% of 959954 checklistsNov 1-7: 0.1% of 709464 checklistsNov 8-14: 0.1% of 693424 checklistsNov 15-21: 0.1% of 653952 checklistsNov 22-30: 0% of 871137 checklistsDec 1-7: 0% of 627591 checklistsDec 8-14: 0% of 642427 checklistsDec 15-21: 0% of 775638 checklistsDec 22-31: 0% of 1132751 checklistsJanFebMarAprMayJunJulAugSepOctNovDec
Share of complete checklists reporting it, by week (4 per month). Grey bars: fewer than 10 checklists, not counted.

Pooled across every state in the data, so it leans toward states with the most birders.

States, in order of first arrivals

StatePatternFirst arrivalsPeakMost gone byPeak %
VermontPasses throughMay 8-14Jun 1-7Aug 1-718%
New HampshireSummer visitorMay 8-14Jun 1-7Aug 1-711%
KansasPasses throughMay 8-14May 22-31Jun 1-75.4%
North DakotaPasses throughMay 8-14May 22-31Jun 8-145.4%
New YorkSummer visitorMay 8-14Jun 1-7Aug 1-76.6%
IowaPasses throughMay 8-14May 22-31Jun 8-145.0%
IndianaPasses throughMay 8-14May 22-31Jun 1-72.9%
MissouriPasses throughMay 8-14May 15-21Jun 1-72.8%
OhioPasses throughMay 8-14May 22-31Jun 1-72.5%
ArkansasPasses throughMay 8-14May 15-21May 22-311.1%
OklahomaPasses throughMay 8-14May 15-21May 22-312.1%
PennsylvaniaSummer visitorMay 8-14Jun 1-7Aug 1-72.1%
MaineSummer visitorMay 15-21Jun 1-7Aug 1-714%
MichiganPasses throughMay 15-21Jun 1-7Aug 1-75.8%
MinnesotaPasses throughMay 15-21Jun 1-7Aug 8-146.9%
WisconsinSummer visitorMay 15-21Jun 1-7Aug 1-76.8%
IllinoisPasses throughMay 15-21May 22-31Jun 1-73.6%
MassachusettsPasses throughMay 15-21Jun 1-7Jun 15-213.1%
NebraskaPasses throughMay 15-21May 22-31Jun 1-72.9%
West VirginiaSummer visitorMay 15-21Jun 1-7Aug 1-73.7%
ConnecticutPasses throughMay 15-21Jun 1-7Aug 1-72.5%
District of ColumbiaPasses throughMay 15-21May 22-31Jun 1-71.2%
South DakotaPasses throughMay 15-21May 22-31Jun 1-71.9%
AlaskaPasses throughMay 22-31Jun 15-21Aug 8-1417%
TexasPasses throughAug 8-14Aug 22-31Sep 15-211.3%
LouisianaPasses throughAug 15-21Sep 1-7Sep 15-212.2%

Passes through: Texas, Louisiana