BirdAnalyst
Species · BCR 5 · BBS 2025 Release · 1966–2024

Fox Sparrow In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestGeneralists

Fox Sparrow in Northern Pacific Rainforest has risen sharply: up 71% on the route-weighted index since 1970.

+71%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 →
79Routes 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 →
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 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 increasecomputed 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 risen sharply in Northern Pacific Rainforest: up 71% on the route-weighted index since 1970.

Fox Sparrow In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Fox Sparrow in Northern Pacific Rainforest is projected to rise about 79% by 2029 — from 2.7 in 2024 to a central estimate of 4.9 (95% range 2.9–6.9). A 5-year backtest shows a typical error of ±57.5%, with 60% of held-out values landing inside the 95% band.

+79%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 →
4.9Projected 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 →
2.9–6.995% 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 →
±57.5%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 Northern Pacific Rainforest is projected to rise about 79% by 2029 — from 2.7 in 2024 to a central estimate of 4.9 (95% range 2.9–6.9). A 5-year backtest shows a typical error of ±57.5%, with 60% 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 →
20254.72.76.6
20264.72.86.7
20274.82.86.7
20284.82.96.8
20294.92.96.9

Routes In Northern Pacific Rainforest

Routes recording Fox Sparrow in Northern Pacific Rainforest.
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 →
Copper RiverALASKA1022011
Thompson PasALASKA752024
South Fork MtnCALIFORNIA272022
HopeALASKA262024
Chichagof IsALASKA232024
Sheep MtnALASKA222017
Harlequin L.ALASKA202024
Pilot CreekCALIFORNIA191996
YakutatALASKA182024
SewardALASKA171992
HoonahALASKA132024
Alpenglow (Short)ALASKA132012
PetersburgALASKA121987
Sitka (Short)ALASKA121992
Elmendorf (Short)ALASKA111985
Moose PassALASKA101992
DirigioCALIFORNIA102014
Stikine RiverALASKA92024
GazelleCALIFORNIA81996
Yakutat (Short)ALASKA61984
Mt ShastaCALIFORNIA62019
RuchOREGON61995
Thorne BayALASKA52010
Kuiu IslandALASKA52010
Lonesome RdgCALIFORNIA52014

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