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

Purple Martin Population Trend in Missouri

All statesAerial insectivores

Purple Martin in Missouri has surged: up 118% on the route-weighted index since 1969.

+118%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 →
93Routes 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 →
57YearsYears 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 MissouriNotable 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 Missouri: up 118% on the route-weighted index since 1969.

Purple Martin Population Forecast in Missouri

If the recent trend holds, Purple Martin in Missouri is projected to stay roughly flat through 2029, near 9.0 (95% range 5.3–13). A 5-year backtest shows a typical error of ±23.8%, with 100% of held-out values landing inside the 95% band.

-9%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 →
9.0Projected 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 →
5.3–1395% 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 →
±23.8%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 Missouri is projected to stay roughly flat through 2029, near 9.0 (95% range 5.3–13). A 5-year backtest shows a typical error of ±23.8%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20258.75.012
20268.85.113
20278.95.213
20288.95.213
20299.05.313

Purple Martin Survey Routes in Missouri

Routes recording Purple Martin in Missouri.
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 →
Syracuse5820241969
Blodgett4220242013
Hayti3920212016
Whitewater3720241996
Cp Girardeau3220241967
Rensselaer3220241972
Auburn2920242014
Eugene2920242013
Washington2819771967
New Hampton2320242015
Reeds2220231974
Miller2120242014
Sticklervill2020241971
Emden2020242017
Centertown1920241973
Akers1820241967
Cole Camp1719901971
Rockingham1720241974
Trenton1720241972
Graniteville1720241982
Kirksville1620241998
Woodlandville1620242013
Kahoka21420242003
Kearney1320241995
Norborne1320232006

Purple Martin Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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