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Species · BCR 12 · BBS 2026 Release · 1966–2025

Hermit Thrush In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionForest birds

Hermit Thrush in Boreal Hardwood Transition has risen sharply: up 66% on the route-weighted index since 1968.

+66%Since 1968TrendPercent 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 →
124Routes 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 →
59YearsYears 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 →

Hermit Thrush has risen sharply in Boreal Hardwood Transition: up 66% on the route-weighted index since 1968.

Hermit Thrush In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Hermit Thrush in Boreal Hardwood Transition is projected to rise about 60% by 2030 — from 8.1 in 2025 to a central estimate of 13 (95% range 8.5–17). A 5-year backtest shows a typical error of ±91%, with 0% of held-out values landing inside the 95% band.

+60%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 →
13Projected 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 →
8.5–1795% 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 →
±91%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, Hermit Thrush in Boreal Hardwood Transition is projected to rise about 60% by 2030 — from 8.1 in 2025 to a central estimate of 13 (95% range 8.5–17). A 5-year backtest shows a typical error of ±91%, with 0% of held-out values landing inside the 95% band.19662030
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 →
2026128.017
2027138.117
2028138.317
2029138.417
2030138.517

Routes In Boreal Hardwood Transition

Routes recording Hermit Thrush in Boreal Hardwood Transition.
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 →
Betchler LksMICHIGAN412025
Land O LakesWISCONSIN402016
GooseneckMICHIGAN372010
ConoverWISCONSIN372025
Cluster LakesMICHIGAN342010
CreightonMICHIGAN272025
Land O' Lakes 2WISCONSIN272025
EnsignMICHIGAN262010
Nett LakeMINNESOTA262024
Brocky LakeMICHIGAN252025
MuskallongeMICHIGAN252024
Pine RiverMICHIGAN252021
SidnawMICHIGAN252025
Scott'S MarshMICHIGAN252010
Big Island LakeMICHIGAN252010
Popple RiverWISCONSIN202025
RacoMICHIGAN182025
Sawbill LndgMINNESOTA182025
MareniscoMICHIGAN172019
Gibbs CityMICHIGAN172025
TahquamenonMICHIGAN162025
Red OakMICHIGAN162022
Isabella 2MICHIGAN162025
Hiawatha NfMICHIGAN162025
Crane LakeMINNESOTA162025

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