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Species · BCR 5 · BBS 2026 Release · 1966–2025

Varied Thrush In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestForest birds

Varied Thrush in Northern Pacific Rainforest has surged: up 308% on the route-weighted index since 1970.

+308%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 →
116Routes 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 →
57YearsYears 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 →

Varied Thrush has surged in Northern Pacific Rainforest: up 308% on the route-weighted index since 1970.

Varied Thrush In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Varied Thrush in Northern Pacific Rainforest is projected to rise about 123% by 2030 — from 8.4 in 2025 to a central estimate of 19 (95% range 13–24). A 5-year backtest shows a typical error of ±50.2%, with 80% of held-out values landing inside the 95% band.

+123%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 →
19Projected 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 →
13–2495% 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 →
±50.2%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, Varied Thrush in Northern Pacific Rainforest is projected to rise about 123% by 2030 — from 8.4 in 2025 to a central estimate of 19 (95% range 13–24). A 5-year backtest shows a typical error of ±50.2%, with 80% of held-out values landing inside the 95% band.19682030
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 →
2026181223
2027181224
2028181224
2029181324
2030191324

Routes In Northern Pacific Rainforest

Routes recording Varied Thrush 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 →
Chichagof IsALASKA1552024
HoonahALASKA1452024
Copper RiverALASKA982011
SewardALASKA951992
Yakutat (Short)ALASKA941984
Kuiu IslandALASKA932010
PetersburgALASKA791987
CraigALASKA692025
Stikine RiverALASKA692024
Redwood N.P. 2CALIFORNIA672013
Thorne Bay 2ALASKA622025
Harlequin L.ALASKA592024
HyderALASKA592009
HainesALASKA552025
Mitkof IsleALASKA532025
Sitka (Short)ALASKA501992
Redwood N.P.CALIFORNIA492010
YakutatALASKA472025
HopeALASKA462025
Whale PassALASKA462024
Moose PassALASKA391992
JuneauALASKA372025
Thorne BayALASKA362012
Zimovia StrtALASKA352025
SkagwayALASKA342025

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