BirdAnalyst
BBS Route · Texas · BCR 35

Marathon Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 73 species recorded across 19 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 →
19Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
2004–2023Span
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
Northern MockingbirdMimidae482023-48%2006
Cassin's SparrowPasserellidae472023-64%2006
Mourning DoveColumbidae422023+177%2006
Cactus WrenTroglodytidae132023-68%2006
Scissor-tailed FlycatcherTyrannidae122023+52%2006
Brown-headed CowbirdIcteridae122022+44%2006
House FinchFringillidae122023+130%2006
Barn SwallowHirundinidae122023+21%2006
House SparrowPasseridae112023-8%2006
Scaled QuailOdontophoridae102023-49%2006
Black-throated SparrowPasserellidae102023+56%2006
Turkey VultureCathartidae92023-29%2006
Ash-throated FlycatcherTyrannidae82023-4%2006
Blue GrosbeakCardinalidae72023-23%2006
Eurasian Collared-DoveColumbidae62023+250%2006
Loggerhead ShrikeLaniidae62023+18%2007
Cassin's KingbirdTyrannidae42023-33%2006
Bell's VireoVireonidae42023+120%2007
Northern CardinalCardinalidae42023+0%2009
White-winged DoveColumbidae32022+260%2006
Red-tailed HawkAccipitridae32023+75%2006
Chihuahuan MeadowlarkIcteridae32023-91%2006
Great-tailed GrackleIcteridae32023+78%2006
PyrrhuloxiaCardinalidae32023-53%2006
Curve-billed ThrasherMimidae32023-56%2006
Swainson's HawkAccipitridae32023-63%2007
Great Horned OwlStrigidae32016+33%2007
MallardAnatidae32016+0%2007
Bronzed CowbirdIcteridae32011n/an/a
Burrowing OwlStrigidae22023+144%2006
Common NighthawkCaprimulgidae22023-75%2006
Western KingbirdTyrannidae22023-83%2006
Scott's OrioleIcteridae22023-22%2006
Orchard OrioleIcteridae22022-20%2006
Bullock's OrioleIcteridae22023-33%2009
Lark SparrowPasserellidae22023-89%2006
Varied BuntingCardinalidae22010+100%2004
Ladder-backed WoodpeckerPicidae22023-29%2011
Summer TanagerCardinalidae22023+0%2007
Common RavenCorvidae22023+14%2009

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