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

Hermit Warbler In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestForest birds

Hermit Warbler in Northern Pacific Rainforest has risen sharply: up 54% on the route-weighted index since 1970.

+54%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 →
105Routes 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 →

Hermit Warbler has risen sharply in Northern Pacific Rainforest: up 54% on the route-weighted index since 1970.

Hermit Warbler In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Hermit Warbler in Northern Pacific Rainforest is projected to rise about 50% by 2030 — from 5.8 in 2025 to a central estimate of 8.6 (95% range 5.0–12). A 5-year backtest shows a typical error of ±25.8%, with 100% of held-out values landing inside the 95% band.

+50%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 →
8.6Projected 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 →
5.0–1295% 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 →
±25.8%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 Warbler in Northern Pacific Rainforest is projected to rise about 50% by 2030 — from 5.8 in 2025 to a central estimate of 8.6 (95% range 5.0–12). A 5-year backtest shows a typical error of ±25.8%, with 100% 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 →
20268.44.812
20278.44.912
20288.54.912
20298.65.012
20308.65.012

Routes In Northern Pacific Rainforest

Routes recording Hermit Warbler 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 →
FisherOREGON782010
Klickitat MtOREGON611996
Blue RiverOREGON512025
Trask SummitOREGON472024
Martins FyCALIFORNIA462009
Pilot CreekCALIFORNIA461996
CinderellaOREGON392025
Hazel CampOREGON362022
Lonesome RdgCALIFORNIA342014
Cool CampOREGON342013
Mt. AdamsWASHINGTON312025
South Fork MtnCALIFORNIA292022
Fisher 2OREGON282025
Redwood N.P. 2CALIFORNIA272013
SelmaOREGON262025
Harlan 2OREGON252025
MolallaOREGON242025
Warner Mtn.OREGON202025
RuchOREGON182025
HarlanOREGON182009
Friday RidgeCALIFORNIA152025
HiouchiCALIFORNIA142014
Secret ValOREGON142025
ShellrockOREGON132024
LaytonvilleCALIFORNIA122025

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