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

Fox Sparrow Population Trend in Oregon

All statesGeneralists

Fox Sparrow in Oregon has fallen sharply: down 66% on the route-weighted index since 1970.

-66%Since 1970TrendPercent 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 →
55Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Fox Sparrow Trends in OregonNotable 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 →

Fox Sparrow has fallen sharply in Oregon: down 66% on the route-weighted index since 1970.

Fox Sparrow Population Forecast in Oregon

If the recent trend holds, Fox Sparrow in Oregon is projected to fall about 75% by 2029 — from 0.96 in 2024 to a central estimate of 0.24 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±79%, with 100% of held-out values landing inside the 95% band.

-75%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 →
0.24Projected 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 →
0.00–1.795% 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%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, Fox Sparrow in Oregon is projected to fall about 75% by 2029 — from 0.96 in 2024 to a central estimate of 0.24 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±79%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20250.350.001.8
20260.320.001.8
20270.290.001.7
20280.270.001.7
20290.240.001.7

Fox Sparrow Survey Routes in Oregon

Routes recording Fox Sparrow in Oregon.
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 →
Davis Lake3820242000
Wizard Falls1820242000
Sisters1020241997
Ruch619951995
Dell Spring419961968
Bly 2420242008
Clearwater420211991
Paunina420241995
Ochoco320212016
Summit Pr220131990
Buchanan219841973
Pendleton220122012
Elk Lake220231972
Badger Creek220241992
Troy220241997
Madras220122012
Warner Mtn.220241992
Whiskey Spg.220111992
Hash Rock220241988
Desolation219991999
Shellrock119941979
Albee120242013
Cool Camp120101968
Lapham Res.120241993
Logdell120241971

Fox Sparrow Population Trend in Other States

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