BirdAnalyst
Species · BCR 28 · BBS 2025 Release · 1966–2024

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 →
360Routes 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 →
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 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.

Forecast

If the recent trend holds, House Sparrow in Appalachian Mountains is projected to fall about 100% by 2029 — from 9.8 in 2024 to a central estimate of 0.00 (95% range 0.00–8.2). A 5-year backtest shows a typical error of ±79.4%, with 20% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–8.295% 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 →
±79.4%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 →
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 →
20252.30.0011
20261.60.009.8
20270.860.009.1
20280.140.008.4
20290.000.008.2

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
WilliamsportMARYLAND1052024
PortersvillePENNSYLVANIA1051988
Drehersville 2PENNSYLVANIA1052024
DrehersvillePENNSYLVANIA1021999
Brunnerville 2PENNSYLVANIA1012024
Doubling GapPENNSYLVANIA961977
SardisPENNSYLVANIA881974
HopeNEW-JERSEY711994
ScheafferstnPENNSYLVANIA712001
Schaefferstown 2PENNSYLVANIA692024
MartinsburgPENNSYLVANIA622024
BrunnervillePENNSYLVANIA612009
ClimerTENNESSEE592004
MarionVIRGINIA561982
AdamsvilleOHIO541989
GeeseytownPENNSYLVANIA532024
SummittALABAMA521981
MidvaleNEW-JERSEY512022
BloomsburyNEW-JERSEY502024
OmegaOHIO482024
NormalvillePENNSYLVANIA481974
NewbernVIRGINIA481982

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