BirdAnalyst
Species · BCR 28 · BBS 2026 Release · 1966–2025

House Sparrow In Appalachian Mountains

All regionsAppalachian MountainsGeneralists

House Sparrow in Appalachian Mountains has collapsed: down 82% on the route-weighted index since 1968.

-82%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 →
361Routes 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 →
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 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 →

House Sparrow has collapsed in Appalachian Mountains: down 82% on the route-weighted index since 1968.

House Sparrow In Appalachian Mountains Population Forecast

If the recent trend holds, House Sparrow in Appalachian Mountains is projected to fall about 100% by 2030 — from 10 in 2025 to a central estimate of 0.00 (95% range 0.00–8.4). A 5-year backtest shows a typical error of ±84.1%, with 0% 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 →
0.00–8.495% 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 →
±84.1%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 Appalachian Mountains is projected to fall about 100% by 2030 — from 10 in 2025 to a central estimate of 0.00 (95% range 0.00–8.4). A 5-year backtest shows a typical error of ±84.1%, with 0% 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 →
20262.10.0011
20271.40.009.8
20280.700.009.1
20290.000.008.4
20300.000.008.4

Routes In Appalachian Mountains

Routes recording House Sparrow in Appalachian Mountains.
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 →
RydePENNSYLVANIA2712005
BirminghamALABAMA1921995
Big FlatPENNSYLVANIA1491981
WilliamsportMARYLAND1232025
PortersvillePENNSYLVANIA1051988
DrehersvillePENNSYLVANIA1021999
Doubling GapPENNSYLVANIA961977
SardisPENNSYLVANIA881974
MartinsburgPENNSYLVANIA802025
Brunnerville 2PENNSYLVANIA782025
WelchWEST-VIRGINIA762025
SmithfieldOHIO752025
HopeNEW-JERSEY711994
ScheafferstnPENNSYLVANIA712001
BrunnervillePENNSYLVANIA612009
ClimerTENNESSEE592004
Drehersville 2PENNSYLVANIA572025
MarionVIRGINIA561982
AdamsvilleOHIO541989
SummittALABAMA521981
MidvaleNEW-JERSEY512022
OmegaOHIO482024
NormalvillePENNSYLVANIA481974
NewbernVIRGINIA481982
Red BankTENNESSEE451978

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