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

House Finch Population Trend in Maryland

All statesGeneralists

House Finch in Maryland has surged: up 73× on the route-weighted index since 1978.

73×Since 1978TrendPercent 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 →
74Routes 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 →
48YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable House Finch 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 →

House Finch has surged in Maryland: up 73× on the route-weighted index since 1978.

House Finch Population Forecast in Maryland

If the recent trend holds, House Finch in Maryland is projected to rise about 23% by 2029 — from 11 in 2024 to a central estimate of 13 (95% range 0.00–27). A 5-year backtest shows a typical error of ±76.4%, with 100% of held-out values landing inside the 95% band.

+23%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 →
13Projected 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 →
0.00–2795% 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 →
±76.4%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, House Finch in Maryland is projected to rise about 23% by 2029 — from 11 in 2024 to a central estimate of 13 (95% range 0.00–27). A 5-year backtest shows a typical error of ±76.4%, with 100% of held-out values landing inside the 95% band.19762029
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 →
2025130.0027
2026130.0027
2027130.0027
2028130.0027
2029130.0027

House Finch Survey Routes in Maryland

Routes recording House Finch 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 →
Silver Spg5319891977
Williamsport4920241980
Olney4420241982
Eklo4320181982
Earlton4020242014
Island Creek3720241991
Jones3419941977
St. George'S Island3420172015
Fair Hill3419961992
Ijamsville3420241986
Madonna3420222009
Pleasant Val2620241982
Wheaton2620241990
Severna Park2220111982
Broomes Isl2119961985
Beltsville1820121981
Jessup1820242013
Pt Republic1719891985
Davidsnville1720241984
Warfieldsbrg1620241981
Pr Frederick1620241991
Theodore1520161981
Forest Grove1520232011
Mt Nebo1419911982
Emmitsburg1420241979

House Finch Population Trend in Other States

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

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