BirdAnalyst
Species · Oregon · BBS 2025 Release · 1966–2024

Purple Martin Population Trend in Oregon

All statesAerial insectivores

Purple Martin in Oregon has surged: up 228% on the route-weighted index since 1973.

+228%Since 1973TrendPercent 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 →
24Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
42YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Purple Martin Trends in OregonNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Purple Martin has surged in Oregon: up 228% on the route-weighted index since 1973.

Purple Martin Population Forecast in Oregon

If the recent trend holds, Purple Martin in Oregon is projected to fall about 18% by 2029 — from 0.29 in 2024 to a central estimate of 0.24 (95% range 0.09–0.38). A 5-year backtest shows a typical error of ±30.2%, with 80% of held-out values landing inside the 95% band.

-18%Change by 2029TrendPercent 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 →
0.24Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.09–0.3895% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±30.2%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Purple Martin in Oregon is projected to fall about 18% by 2029 — from 0.29 in 2024 to a central estimate of 0.24 (95% range 0.09–0.38). A 5-year backtest shows a typical error of ±30.2%, with 80% of held-out values landing inside the 95% band.19702029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.220.080.37
20260.230.080.37
20270.230.090.38
20280.230.090.38
20290.240.090.38

Purple Martin Survey Routes in Oregon

Routes recording Purple Martin in Oregon.
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 →
Nicolai Mtn.1120241998
Glasgow1020241987
Hazel Camp820221978
Wedderburn620231973
Hauser419791970
Adair220182018
Elkton220232023
Badger Creek220222022
Coquille220242010
Tualatin120242005
Santiam120242016
Scappoose120222021
Umpqua120241970
Dell Spring119761976
Days Creek119971995
Modoc Point119821982
Scio120241981
Svensen119921992
Mt Hood120222022
Green120231994
Mcminnville120112011
Salem120222018
Lorane120231998
Selma119931993

Purple Martin Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.