BirdAnalyst
Species · BCR 14 · BBS 2025 Release · 1966–2024

House Sparrow In Atlantic Northern Forest

All regionsAtlantic Northern ForestGeneralists

House Sparrow in Atlantic Northern Forest has fallen sharply: down 70% on the route-weighted index since 1968.

-70%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 →
124Routes 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 fallen sharply in Atlantic Northern Forest: down 70% on the route-weighted index since 1968.

Forecast

If the recent trend holds, House Sparrow in Atlantic Northern Forest is projected to fall about 100% by 2029 — from 3.7 in 2024 to a central estimate of 0.00 (95% range 0.00–2.8). A 5-year backtest shows a typical error of ±99.8%, with 60% 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 →
0.00–2.895% 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 →
±99.8%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 Atlantic Northern Forest is projected to fall about 100% by 2029 — from 3.7 in 2024 to a central estimate of 0.00 (95% range 0.00–2.8). A 5-year backtest shows a typical error of ±99.8%, 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 →
20250.280.003.1
20260.130.003.0
20270.000.002.8
20280.000.002.8
20290.000.002.8

Routes In Atlantic Northern Forest

Routes recording House Sparrow in Atlantic Northern Forest.
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 →
CheshireMASSACHUSETTS521994
WestbrookMAINE392024
CornvilleMAINE322024
BrooksMAINE242018
Bowdoin CtrMAINE182021
Dexter LakeNEW-YORK181969
LudlowMAINE171995
FitzwilliamNEW-HAMPSHIRE172024
PittsfieldMASSACHUSETTS162016
GlenNEW-HAMPSHIRE162024
ConcordNEW-HAMPSHIRE152024
New HartfordCONNECTICUT131987
FletcherVERMONT132024
ManchesterMAINE121995
MarlboroVERMONT112024
East TroyMAINE102017
RomeMAINE102024
BrownfieldMAINE102009
MarlowNEW-HAMPSHIRE102024
GaysvilleVERMONT102019
BiddefordMAINE92019
WatervilleVERMONT91980
CooperMAINE81981
Moose RiverMAINE81986
PeterboroughNEW-HAMPSHIRE82024

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