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

House Sparrow Population Trend in Maryland

All statesGeneralists

House Sparrow in Maryland has collapsed: down 81% on the route-weighted index since 1968.

-81%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 House Sparrow 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 →

House Sparrow has collapsed in Maryland: down 81% on the route-weighted index since 1968.

House Sparrow Population Forecast in Maryland

If the recent trend holds, House Sparrow in Maryland is projected to fall about 100% by 2030 — from 23 in 2025 to a central estimate of 0.00 (95% range 0.00–21). A 5-year backtest shows a typical error of ±73.3%, with 80% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–2195% 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 →
±73.3%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 Sparrow in Maryland is projected to fall about 100% by 2030 — from 23 in 2025 to a central estimate of 0.00 (95% range 0.00–21). A 5-year backtest shows a typical error of ±73.3%, with 80% 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 →
20265.60.0026
20274.10.0025
20282.60.0023
20291.10.0022
20300.000.0021

House Sparrow Survey Routes in Maryland

Routes recording House Sparrow 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 →
Sinepuxent24119781966
Largo15819811966
Snow Hill13119761966
Madonna12520222009
Williamsport12320251966
Wheaton10920251990
Jones8319941966
Silver Spg8119891966
Emmitsburg7120251966
Ijamsville6920251986
Upper Xrds6020081966
Earlton5820242014
Eklo5120181966
Pleasant Val5020251966
Norwood4720121966
Forest Grove4420232011
Wolfsville4320251966
Olney3920251966
Bachman Mill3620251966
St. George'S Island3520172015
Cheltenham3420041966
Warfieldsbrg3120251966
Bald Friar3119961992
Fruitland3019981966
La Plata2920091966

House Sparrow Population Trend in Other States

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

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