BirdAnalyst
Species · Maryland · BBS 2026 Release · 1966–2025

Common Grackle Population Trend in Maryland

All statesGeneralists

Common Grackle in Maryland has fallen sharply: down 75% on the route-weighted index since 1968.

-75%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 →
76Routes 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 →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Common Grackle Trends in MarylandNotable 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 fallen sharply in Maryland: down 75% on the route-weighted index since 1968.

Common Grackle Population Forecast in Maryland

If the recent trend holds, Common Grackle in Maryland is projected to fall about 48% by 2030 — from 47 in 2025 to a central estimate of 25 (95% range 0.00–51). A 5-year backtest shows a typical error of ±13.8%, with 100% of held-out values landing inside the 95% band.

-48%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 →
25Projected 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 →
0.00–5195% 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 →
±13.8%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, Common Grackle in Maryland is projected to fall about 48% by 2030 — from 47 in 2025 to a central estimate of 25 (95% range 0.00–51). A 5-year backtest shows a typical error of ±13.8%, with 100% of held-out values landing inside the 95% band.19662030
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 →
2026336.559
2027314.457
2028292.355
2029270.1753
2030250.0051

Common Grackle Survey Routes in Maryland

Routes recording Common Grackle in Maryland.
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 →
Williamsport35520251966
Harmony26420171966
Cokesbury23820251966
Fruitland18119981966
Sinepuxent16019781966
Tall Timbers14520141966
Snow Hill14219761966
Matthews11420251966
Broomes Isl10419961966
Piney Neck10420251966
Grove Neck10019961992
Melitota9820251966
Honga9020251966
Golden Hill8020251966
Bald Friar7519961992
Fair Hill7219961992
Cheltenham6720041966
Pt Republic6519891966
Vienna6420251966
Forest Grove5820232011
Elkton5720251966
Millington5620251966
Largo5519811966
Indiantown4920141977
Potomac Park4720251970

Common Grackle Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

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