BirdAnalyst
BBS Route · Texas · BCR 35

Marathon Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 73 species recorded across 20 survey years, still active.

73Species 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 →
20Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
2004–2025Span
1Observers

Bird Species Found on Texas Marathon

Top 40 of 73 species by most recent count. Each links to its species trend.

Species recorded on the Marathon 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
Cassin's SparrowPasserellidae1022025-26%2006
Northern MockingbirdMimidae462025-58%2006
Turkey VultureCathartidae242025-21%2006
Scaled QuailOdontophoridae202025-44%2006
House SparrowPasseridae182025-6%2006
Black-throated SparrowPasserellidae142025+200%2006
Ash-throated FlycatcherTyrannidae102025+0%2006
Chihuahuan MeadowlarkIcteridae92025-89%2006
Cactus WrenTroglodytidae92025-74%2006
Mourning DoveColumbidae82025+191%2006
Barn SwallowHirundinidae82025+17%2006
Blue GrosbeakCardinalidae72025-27%2006
Common NighthawkCaprimulgidae62025-79%2006
Scott's OrioleIcteridae62025-44%2006
Lark SparrowPasserellidae62025-81%2006
Bell's VireoVireonidae52025+180%2007
Common RavenCorvidae52025+57%2009
Yellow-breasted ChatIcteriidae52025+200%2012
Red-tailed HawkAccipitridae42025+100%2006
Cave SwallowHirundinidae42025-95%2006
Eurasian Collared-DoveColumbidae42025+125%2006
Painted BuntingCardinalidae42025+14%2008
White-winged DoveColumbidae32022+260%2006
Great-tailed GrackleIcteridae32023+78%2006
House FinchFringillidae32025+130%2006
Great Horned OwlStrigidae32016+33%2007
Loggerhead ShrikeLaniidae32025+9%2007
Cliff SwallowHirundinidae32025-20%2013
Bronzed CowbirdIcteridae32011n/an/a
Burrowing OwlStrigidae22025+89%2006
Cassin's KingbirdTyrannidae22025-50%2006
Brown-headed CowbirdIcteridae22025+38%2006
Orchard OrioleIcteridae22025+0%2006
Bullock's OrioleIcteridae22023-33%2009
Canyon TowheePasserellidae22025-55%2006
PyrrhuloxiaCardinalidae22025-59%2006
Varied BuntingCardinalidae22010+100%2004
Ladder-backed WoodpeckerPicidae22023-29%2011
Summer TanagerCardinalidae22023+0%2007
DickcisselCardinalidae22019n/an/a

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. A route is a sample, not a census.