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Species · BCR 2 · BBS 2026 Release · 1966–2025

Northern Waterthrush In BCR 2

All regionsBCR 2Forest birds

Northern Waterthrush in BCR 2 has fallen sharply: down 58% on the route-weighted index since 1987.

-58%Since 1987TrendPercent 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 →
35YearsYears 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 declinecomputed 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 fallen sharply in BCR 2: down 58% on the route-weighted index since 1987.

Northern Waterthrush In BCR 2 Population Forecast

If the recent trend holds, Northern Waterthrush in BCR 2 is projected to rise about 107% by 2030 — from 1.2 in 2025 to a central estimate of 2.4 (95% range 0.00–13). A 5-year backtest shows a typical error of ±113.9%, with 100% of held-out values landing inside the 95% band.

+107%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 →
2.4Projected 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 →
0.00–1395% 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 →
±113.9%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 BCR 2 is projected to rise about 107% by 2030 — from 1.2 in 2025 to a central estimate of 2.4 (95% range 0.00–13). A 5-year backtest shows a typical error of ±113.9%, with 100% of held-out values landing inside the 95% band.19842030
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 →
20263.80.0015
20273.50.0014
20283.10.0014
20292.80.0014
20302.40.0013

Routes In BCR 2

Routes recording Northern Waterthrush 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 →
Gweek RiverALASKA1292002
TupuknukALASKA1261995
CouncilALASKA472024
Selawik (Short)ALASKA421987
Dillingham (Short)ALASKA391984
Togiak RiverALASKA362005
Salmon LakeALASKA322024
NomeALASKA212023
Goodnews BayALASKA182005
Kugarak (Short)ALASKA181987
Kanektok RivALASKA152005
St. Mary'SALASKA72014
DillinghamALASKA52019
Cape NomeALASKA42024
Kotzebue (Short)ALASKA41994
King SalmonALASKA32025
TellerALASKA32024
KotzebueALASKA32025
Katmai N.P.ALASKA12025

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