BirdAnalyst
Species · BCR 27 · BBS 2025 Release · 1966–2024

Common Grackle In Southeastern Coastal Plain

All regionsSoutheastern Coastal PlainGeneralists

Common Grackle in Southeastern Coastal Plain has collapsed: down 80% on the route-weighted index since 1968.

-80%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 →
337Routes 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 Southeastern Coastal Plain: down 80% on the route-weighted index since 1968.

Common Grackle In Southeastern Coastal Plain Population Forecast

If the recent trend holds, Common Grackle in Southeastern Coastal Plain is projected to fall about 60% by 2029 — from 10 in 2024 to a central estimate of 4.1 (95% range 0.00–13). A 5-year backtest shows a typical error of ±17%, with 100% of held-out values landing inside the 95% band.

-60%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 →
4.1Projected 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 →
0.00–1395% 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 →
±17%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 Southeastern Coastal Plain is projected to fall about 60% by 2029 — from 10 in 2024 to a central estimate of 4.1 (95% range 0.00–13). A 5-year backtest shows a typical error of ±17%, 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 →
20257.80.0017
20266.90.0016
20276.00.0015
20285.00.0014
20294.10.0013

Routes In Southeastern Coastal Plain

Routes recording Common Grackle in Southeastern Coastal Plain.
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 →
Jarvisburg 2NORTH-CAROLINA6092022
BeargrassNORTH-CAROLINA3271981
Johns IsleSOUTH-CAROLINA2531979
Alabama PtALABAMA2322003
JarvisburgNORTH-CAROLINA2061999
FoleyALABAMA1591984
GrandyNORTH-CAROLINA1481975
BackbayVIRGINIA1341974
ShallotteNORTH-CAROLINA1321991
ElbertaALABAMA1112022
MashoesNORTH-CAROLINA1011982
Dauphin IsALABAMA811990
LovedaleFLORIDA812011
FairmontNORTH-CAROLINA781981
CornlandVIRGINIA782014
HertfordNORTH-CAROLINA712024
Ft Waltn BchFLORIDA662011
Boykin Ml PdSOUTH-CAROLINA651968
WeberGEORGIA622024
CaliforniaNORTH-CAROLINA612013
MattamuskeetNORTH-CAROLINA582021
St. ElmoALABAMA542021
SpeedNORTH-CAROLINA542024
MaconMISSISSIPPI512024
Santa RosaFLORIDA472003

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