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

Great-tailed Grackle Population Trend in Missouri

All statesGeneralists

Great-tailed Grackle in Missouri has fallen sharply: down 56% on the route-weighted index since 1993.

-56%Since 1993TrendPercent 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 →
23Routes 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 →
30YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Great-tailed Grackle 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 declinecomputed 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 →

Great-tailed Grackle has fallen sharply in Missouri: down 56% on the route-weighted index since 1993.

Great-tailed Grackle Population Forecast in Missouri

If the recent trend holds, Great-tailed Grackle in Missouri is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.30). A 5-year backtest shows a typical error of ±40%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.01Projected 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 →
0.00–0.3095% 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 →
±40%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, Great-tailed Grackle in Missouri is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.30). A 5-year backtest shows a typical error of ±40%, with 100% of held-out values landing inside the 95% band.19882029
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 →
20250.030.000.33
20260.030.000.32
20270.020.000.32
20280.010.000.31
20290.010.000.30

Great-tailed Grackle Survey Routes in Missouri

Routes recording Great-tailed Grackle 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 →
Cassville620131995
Madison520022002
Cameron420072005
Syracuse419961996
Rockingham319931992
Frazier320181988
New Point320192005
Kingsville319991993
Pineville220142011
Reeds220121994
Centertown219971997
Diamond220242021
Osage Beach220071997
Mcfall220162000
Sweden120092009
Handley119971997
Graydon120172005
Hayden120072007
Ohio120041994
Huntsville120182018
Marshfield120032003
Laclede120112010
Kearney120092009

Great-tailed Grackle Population Trend in Other States

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