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Species · BCR 26 · BBS 2025 Release · 1966–2024

Common Grackle In Mississippi Alluvial Valley

All regionsMississippi Alluvial ValleyGeneralists

Common Grackle in Mississippi Alluvial Valley has collapsed: down 85% on the route-weighted index since 1968.

-85%Since 1968TrendPercent 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 →
72Routes 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 →

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 →

Common Grackle has collapsed in Mississippi Alluvial Valley: down 85% on the route-weighted index since 1968.

Common Grackle In Mississippi Alluvial Valley Population Forecast

If the recent trend holds, Common Grackle in Mississippi Alluvial Valley is projected to fall about 88% by 2029 — from 21 in 2024 to a central estimate of 2.5 (95% range 0.00–41). A 5-year backtest shows a typical error of ±44.5%, with 100% of held-out values landing inside the 95% band.

-88%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 →
2.5Projected 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 →
0.00–4195% 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 →
±44.5%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, Common Grackle in Mississippi Alluvial Valley is projected to fall about 88% by 2029 — from 21 in 2024 to a central estimate of 2.5 (95% range 0.00–41). A 5-year backtest shows a typical error of ±44.5%, with 100% of held-out values landing inside the 95% band.19662029
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 →
202510.00.0048
20268.10.0046
20276.30.0045
20284.40.0043
20292.50.0041

Routes In Mississippi Alluvial Valley

Routes recording Common Grackle in Mississippi Alluvial Valley.
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 →
Morgan CityLOUISIANA2601986
HaytiMISSOURI1682021
CarlisleLOUISIANA1361988
GibsonLOUISIANA1142019
BerwickLOUISIANA1032018
Morgan CityLOUISIANA1022022
DellARKANSAS832024
WilsonARKANSAS802024
BlodgettMISSOURI752024
LaroseLOUISIANA741992
River RoadLOUISIANA652024
CommerceMISSISSIPPI651993
AugustaARKANSAS632001
WhittonARKANSAS611991
TchulaMISSISSIPPI491975
HarrisburgARKANSAS472019
PawpawTENNESSEE442012
GonzalesLOUISIANA422019
BardwellKENTUCKY382003
DeventerMISSOURI372024
RamahLOUISIANA362024
TiptonvilleTENNESSEE342023
Pawpaw 2TENNESSEE342023
KeystoneLOUISIANA332013
ShawLOUISIANA332024

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