BirdAnalyst
Species · BCR 16 · BBS 2025 Release · 1966–2024

Hermit Thrush In Southern Rockies / Colorado Plateau

All regionsSouthern Rockies / Colorado PlateauForest birds

Hermit Thrush in Southern Rockies / Colorado Plateau has surged: up 300% on the route-weighted index since 1970.

+300%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 →
141Routes 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 →

Hermit Thrush has surged in Southern Rockies / Colorado Plateau: up 300% on the route-weighted index since 1970.

Hermit Thrush In Southern Rockies / Colorado Plateau Population Forecast

If the recent trend holds, Hermit Thrush in Southern Rockies / Colorado Plateau is projected to rise about 28% by 2029 — from 6.4 in 2024 to a central estimate of 8.2 (95% range 5.9–10). A 5-year backtest shows a typical error of ±35.8%, with 60% of held-out values landing inside the 95% band.

+28%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 →
8.2Projected 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 →
5.9–1095% 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 →
±35.8%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 Southern Rockies / Colorado Plateau is projected to rise about 28% by 2029 — from 6.4 in 2024 to a central estimate of 8.2 (95% range 5.9–10). A 5-year backtest shows a typical error of ±35.8%, 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 →
20257.85.510
20267.95.610
20278.05.710
20288.15.810
20298.25.910

Routes In Southern Rockies / Colorado Plateau

Routes recording Hermit Thrush in Southern Rockies / Colorado Plateau.
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 →
Buffalo ParkCOLORADO772023
Grizzly RdgeUTAH492024
Navajo LakeUTAH482024
Fox ParkWYOMING482024
Pinos CreekCOLORADO441990
TsaileARIZONA342023
Mount EvansCOLORADO342024
South ForkCOLORADO332024
Haycamp MesaCOLORADO322024
Dry ParkARIZONA292024
Mcphee Res.COLORADO272024
Angel FireNEW-MEXICO262002
Baxter PassCOLORADO252024
Cochetopa PassCOLORADO252024
Fish Lake NfUTAH252024
PinonCOLORADO242024
La SalUTAH242000
Heber Mtn.UTAH242024
La Sal 3UTAH232024
Red Spur Mtn.UTAH232023
Lake CityCOLORADO222003
Rollins PassCOLORADO222022
Wasatch NfUTAH212024
Deadman Rd.COLORADO202024
La Sal 2UTAH202006

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