BirdAnalyst
BBS Route · Colorado · BCR 18

Last Chance Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 76 species recorded across 49 survey years, no longer active.

76Species RecordedSpecies recordedDistinct species detected on standard-protocol BBS runs here across all years on record — a measure of survey breadth, not a complete checklist.Full methodology →
49Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
1968–2016Span
3Observers

Bird Species Found on Colorado Last Chance

Top 40 of 76 species by most recent count. Each links to its species trend.

Species recorded on the Last Chance route.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →History
Lark BuntingPasserellidae1122016-68%1970
Western MeadowlarkIcteridae912016-12%1970
Mourning DoveColumbidae672016+35%1970
Horned LarkAlaudidae572016-74%1970
Red-winged BlackbirdIcteridae222016+138%1970
Grasshopper SparrowPasserellidae222015+275%1972
Western KingbirdTyrannidae162016-12%1970
Long-billed CurlewScolopacidae111981n/an/a
GadwallAnatidae91974n/an/a
Brown-headed CowbirdIcteridae82015+22%1978
Red-tailed HawkAccipitridae72016-16%1982
American White PelicanPelecanidae72009-30%1993
Cliff SwallowHirundinidae62005n/an/a
Eurasian Collared-DoveColumbidae62012+500%2010
Barn SwallowHirundinidae52015+125%1970
Double-crested CormorantPhalacrocoracidae51994+150%1991
MallardAnatidae42015+0%1971
European StarlingSturnidae42013-38%1972
Northern PintailAnatidae42003-64%1973
Ruddy DuckAnatidae41987n/an/a
Burrowing OwlStrigidae32012+125%1970
Black-billed MagpieCorvidae31989+200%1968
House SparrowPasseridae32016-87%1970
Brown ThrasherMimidae31999+100%1993
Swainson's HawkAccipitridae32015-39%1971
Green-winged TealAnatidae31994+0%1976
Say's PhoebeTyrannidae22016-42%1970
Brewer's BlackbirdIcteridae22013-56%1970
Brewer's SparrowPasserellidae22015+0%1973
American AvocetRecurvirostridae21999-20%1972
Common GrackleIcteridae22015+50%1973
Northern BobwhiteOdontophoridae21974n/an/a
Short-eared OwlStrigidae21983n/an/a
Rock WrenTroglodytidae21984n/an/a
Pied-billed GrebePodicipedidae22016+100%1988
Black-crowned Night HeronArdeidae22004+100%1988
Wilson's WarblerParulidae22000+100%1989
Northern ShovelerAnatidae22015-71%2000
American WigeonAnatidae22005n/an/a
Song SparrowPasserellidae22016n/an/a

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. A route is a sample, not a census.