BirdAnalyst
Species · BCR 11 · BBS 2025 Release · 1966–2024

Northern Waterthrush In Prairie Potholes

All regionsPrairie PotholesForest birds

Northern Waterthrush in Prairie Potholes has surged: up 546% on the route-weighted index since 1981.

+546%Since 1981TrendPercent 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 →
5Routes 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 →
38YearsYears 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 Prairie Potholes: up 546% on the route-weighted index since 1981.

Northern Waterthrush In Prairie Potholes Population Forecast

If the recent trend holds, Northern Waterthrush in Prairie Potholes is projected to rise about 34% by 2029 — from 0.45 in 2024 to a central estimate of 0.60 (95% range 0.38–0.83). A 5-year backtest shows a typical error of ±27.2%, with 80% of held-out values landing inside the 95% band.

+34%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 →
0.60Projected 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 →
0.38–0.8395% 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 →
±27.2%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 Prairie Potholes is projected to rise about 34% by 2029 — from 0.45 in 2024 to a central estimate of 0.60 (95% range 0.38–0.83). A 5-year backtest shows a typical error of ±27.2%, with 80% of held-out values landing inside the 95% band.19692029
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 →
20250.560.340.79
20260.570.350.80
20270.580.360.81
20280.590.370.82
20290.600.380.83

Routes In Prairie Potholes

Routes recording Northern Waterthrush in Prairie Potholes.
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 →
Turtle MtnsNORTH-DAKOTA312024
ErieMINNESOTA21989
OkleeMINNESOTA11982
BadgerMINNESOTA12000
DenbighNORTH-DAKOTA12024

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