Rare Birds in Colorado
Our list for Colorado has 72 rare birds recorded regularly there: 10 residents, 13 summer visitors, 14 winter visitors and 35 passage migrants
Most likely in October
GBIF · OctShare of all bird records in Colorado in October, 2019–2024. Each month links to that month’s page.
All 72, most common first
Red-necked GrebePodiceps grisegenaWinter visitorRare40–50 cmRegularly Jul–Mar
Common TernSterna hirundoPassage migrantRare31–35 cmRegularly Jun–Oct
Broad-winged HawkButeo platypterusPassage migrantRare34–44 cmRegularly Apr–Oct
Eastern BluebirdSialia sialisWinter visitorRare16–21 cmRecorded all year
KittiwakeRissa tridactylaPassage migrantRare37–41 cmRegularly Nov–Dec
Upland SandpiperBartramia longicaudaSummer visitorRare28–32 cmRegularly May–Sep
Nashville WarblerLeiothlypis ruficapillaPassage migrantRare11–13 cmRegularly Apr–Nov
DunlinCalidris alpinaWinter visitorRare16–22 cmRegularly Oct–Apr
Yellow-bellied SapsuckerSphyrapicus variusWinter visitorRare19–22 cmRegularly Sep–Mar
Blackpoll WarblerSetophaga striataPassage migrantRare13–15 cmRegularly May–Sep
Northern CardinalCardinalis cardinalisResidentRare21–23 cmRecorded all year
Brent GooseBranta berniclaPassage migrantRare55–66 cmRegularly Nov–Jan
Glaucous GullLarus hyperboreusWinter visitorRare62–68 cmRegularly Dec–Mar
Northern Pygmy-owlGlaucidium gnomaResidentRare15–17 cmRecorded all year
American Golden-PloverPluvialis dominicaPassage migrantRare24–28 cmRegularly Sep–Nov
VeeryCatharus fuscescensSummer visitorRare16–19 cmRegularly May–Sep
Tennessee WarblerLeiothlypis peregrinaPassage migrantRare10–13 cmRegularly May–Nov
Chestnut-sided WarblerSetophaga pensylvanicaPassage migrantRare10–14 cmRegularly May–Oct
Baltimore OrioleIcterus galbulaSummer visitorRare17–19 cmRegularly May–Sep
Western Screech-owlMegascops kennicottiiWinter visitorRare19–25 cmRecorded all year
Purple MartinProgne subisSummer visitorRare18–20 cmRegularly May–Sep
Red-bellied WoodpeckerMelanerpes carolinusResidentRare23–26 cmRecorded all year
Great Crested FlycatcherMyiarchus crinitusSummer visitorRare17–22 cmRegularly May–Sep
Data: EOD – eBird Observation Dataset (Cornell Lab of Ornithology), accessed via GBIF.org, CC BY 4.0. Records from 2019–2024, aggregated and filtered by Birdfact. How these lists are made