BirdAnalyst
Species · BCR 2 · BBS 2025 Release · 1966–2024

Varied Thrush In BCR 2

All regionsBCR 2Forest birds

Varied Thrush in BCR 2 has held roughly steady: down 4% on the route-weighted index since 1985.

-4%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 →
41YearsYears 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 rise about 44% by 2029 — from 12 in 2024 to a central estimate of 17 (95% range 3.7–30). A 5-year backtest shows a typical error of ±75%, with 100% of held-out values landing inside the 95% band.

+44%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 →
17Projected 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 →
3.7–3095% 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 →
±75%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 rise about 44% by 2029 — from 12 in 2024 to a central estimate of 17 (95% range 3.7–30). A 5-year backtest shows a typical error of ±75%, with 100% of held-out values landing inside the 95% band.19832029
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 →
2025163.229
2026163.430
2027173.530
2028173.630
2029173.730

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 →
ChiniakALASKA532024
TupuknukALASKA521995
DillinghamALASKA452019
Dillingham (Short)ALASKA291984
Katmai N.P.ALASKA282022
King SalmonALASKA242024
Kodiak 2ALASKA232024
St. Mary'SALASKA202014
Gweek RiverALASKA192002
KodiakALASKA31984
Salmon LakeALASKA32024
Selawik (Short)ALASKA31987
CouncilALASKA22024
Cape NomeALASKA12019
Togiak RiverALASKA12003
Kanektok RivALASKA12004

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