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Species · BCR 2 · BBS 2026 Release · 1966–2025

Varied Thrush In BCR 2

All regionsBCR 2Forest birds

Varied Thrush in BCR 2 has increased: up 31% on the route-weighted index since 1985.

+31%Since 1985TrendPercent 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 →
16Routes 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 →
42YearsYears 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 →

No notable trend signals for Varied Thrush in BCR 2. See the full index history below.

Varied Thrush In BCR 2 Population Forecast

If the recent trend holds, Varied Thrush in BCR 2 is projected to fall about 19% by 2030 — from 22 in 2025 to a central estimate of 17 (95% range 4.5–31). A 5-year backtest shows a typical error of ±76.4%, with 100% of held-out values landing inside the 95% band.

-19%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 →
17Projected 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 →
4.5–3195% 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 →
±76.4%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 →
If the recent trend holds, Varied Thrush in BCR 2 is projected to fall about 19% by 2030 — from 22 in 2025 to a central estimate of 17 (95% range 4.5–31). A 5-year backtest shows a typical error of ±76.4%, with 100% of held-out values landing inside the 95% band.19832030
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 →
2026173.930
2027174.130
2028174.230
2029174.330
2030174.531

Routes In BCR 2

Routes recording Varied Thrush in BCR 2.
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 →
TupuknukALASKA521995
ChiniakALASKA502025
DillinghamALASKA452019
Kodiak 2ALASKA312025
Katmai N.P.ALASKA292025
Dillingham (Short)ALASKA291984
St. Mary'SALASKA202014
King SalmonALASKA192025
Gweek RiverALASKA192002
KodiakALASKA31984
Salmon LakeALASKA32024
Selawik (Short)ALASKA31987
CouncilALASKA22024
Cape NomeALASKA12019
Togiak RiverALASKA12003
Kanektok RivALASKA12004

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