BirdAnalyst
Species · BCR 19 · BBS 2026 Release · 1966–2025

Purple Martin In Central Mixed Grass Prairie

All regionsCentral Mixed Grass PrairieAerial insectivores

Purple Martin in Central Mixed Grass Prairie has edged down: down 10% on the route-weighted index since 1969.

-10%Since 1969TrendPercent 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 →
78Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

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

No notable trend signals for Purple Martin in Central Mixed Grass Prairie. See the full index history below.

Purple Martin In Central Mixed Grass Prairie Population Forecast

If the recent trend holds, Purple Martin in Central Mixed Grass Prairie is projected to rise about 28% by 2030 — from 0.64 in 2025 to a central estimate of 0.82 (95% range 0.28–1.4). A 5-year backtest shows a typical error of ±54.1%, with 100% of held-out values landing inside the 95% band.

+28%Change by 2030TrendPercent 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 →
0.82Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.28–1.495% 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 →
±54.1%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 Central Mixed Grass Prairie is projected to rise about 28% by 2030 — from 0.64 in 2025 to a central estimate of 0.82 (95% range 0.28–1.4). A 5-year backtest shows a typical error of ±54.1%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20260.790.241.3
20270.800.251.3
20280.800.261.3
20290.810.271.4
20300.820.281.4

Routes In Central Mixed Grass Prairie

Routes recording Purple Martin in Central Mixed Grass Prairie.
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 →
VerdenOKLAHOMA402015
LeovilleKANSAS111970
JohnstownNEBRASKA112019
BerwetKANSAS102025
HaysKANSAS82008
JamestownKANSAS82018
CashionOKLAHOMA82023
Pear ValleyTEXAS82025
WallTEXAS82022
WellingtonKANSAS62025
RosstonOKLAHOMA61976
ArapahoOKLAHOMA62007
ColonyOKLAHOMA61995
GrayKANSAS52018
WeinertTEXAS51980
HaskellTEXAS52021
KearneyNEBRASKA42025
AlmeriaNEBRASKA41980
HanoverKANSAS32023
HollenbergKANSAS32025
MisslerKANSAS31998
HodgesKANSAS32014
Eagle CityOKLAHOMA32004
WakitaOKLAHOMA31982
TegardenOKLAHOMA31976

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.