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

American Goldfinch Population Trend in Maryland

All statesGeneralists

American Goldfinch in Maryland has risen sharply: up 66% on the route-weighted index since 1968.

+66%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 →
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 American Goldfinch 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 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 →

American Goldfinch has risen sharply in Maryland: up 66% on the route-weighted index since 1968.

American Goldfinch Population Forecast in Maryland

If the recent trend holds, American Goldfinch in Maryland is projected to stay roughly flat through 2029, near 15 (95% range 11–19). A 5-year backtest shows a typical error of ±22.9%, with 60% of held-out values landing inside the 95% band.

+1%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 →
15Projected 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 →
11–1995% 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 →
±22.9%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, American Goldfinch in Maryland is projected to stay roughly flat through 2029, near 15 (95% range 11–19). A 5-year backtest shows a typical error of ±22.9%, with 60% 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 →
2025151118
2026151119
2027151119
2028151119
2029151119

American Goldfinch Survey Routes in Maryland

Routes recording American Goldfinch 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 →
Ijamsville3720241986
Jennings3620241995
Wolfsville3320241966
Eklo3220181966
Finzel3120241995
Williamsport2720241966
Smithsburg2720141966
Olney2720241966
Davidsnville2720241982
Island Creek2720241991
Emmitsburg2620241966
Earlton2620242014
La Plata2320091966
Madonna2020222009
Pr Frederick2020241991
Beltsville1920121966
Hughesville1920241966
Norwood1720121966
Walnut1720241999
Cokesbury1620241966
Forest Grove1620232011
Pomonkey1520241966
Piney Grove1420241995
Severna Park1420111982
Nottingham1420242005

American Goldfinch Population Trend in Other States

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

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