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Species · BCR 5 · BBS 2025 Release · 1966–2024

Northern Waterthrush In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestForest birds

Northern Waterthrush in Northern Pacific Rainforest has surged: up 90% on the route-weighted index since 1983.

+90%Since 1983TrendPercent 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 →
19Routes 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 →
37YearsYears 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 →

Northern Waterthrush has surged in Northern Pacific Rainforest: up 90% on the route-weighted index since 1983.

Northern Waterthrush In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Northern Waterthrush in Northern Pacific Rainforest is projected to fall about 37% by 2029 — from 0.35 in 2024 to a central estimate of 0.22 (95% range 0.04–0.39). A 5-year backtest shows a typical error of ±38.1%, with 60% of held-out values landing inside the 95% band.

-37%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 →
0.22Projected 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 →
0.04–0.3995% 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 →
±38.1%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, Northern Waterthrush in Northern Pacific Rainforest is projected to fall about 37% by 2029 — from 0.35 in 2024 to a central estimate of 0.22 (95% range 0.04–0.39). A 5-year backtest shows a typical error of ±38.1%, with 60% of held-out values landing inside the 95% band.19712029
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 →
20250.210.030.38
20260.210.040.38
20270.210.040.38
20280.210.040.39
20290.220.040.39

Routes In Northern Pacific Rainforest

Routes recording Northern Waterthrush 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 →
Thompson PasALASKA152024
Elmendorf (Short)ALASKA81985
HainesALASKA42024
Copper RiverALASKA42011
SewardALASKA31984
Moose PassALASKA31985
HopeALASKA32024
Alpenglow (Short)ALASKA32012
Stikine RiverALASKA32024
KetchikanALASKA21971
YakutatALASKA22004
Kenai Lake (Short)ALASKA21984
JuneauALASKA12023
CordovaALASKA12016
Sheep MtnALASKA12011
Thorne BayALASKA11990
Harlequin L.ALASKA12021
SkagwayALASKA12024
HyderALASKA12004

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