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

Bufflehead In Prairie Potholes

All regionsPrairie PotholesWaterfowl

Bufflehead in Prairie Potholes has surged: up 938% on the route-weighted index since 1985.

+938%Since 1985TrendPercent 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 →
15Routes 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 →

Bufflehead has surged in Prairie Potholes: up 938% on the route-weighted index since 1985.

Bufflehead In Prairie Potholes Population Forecast

If the recent trend holds, Bufflehead in Prairie Potholes is projected to fall about 53% by 2029 — from 1.0 in 2024 to a central estimate of 0.47 (95% range 0.02–0.91). A 5-year backtest shows a typical error of ±55.9%, with 40% of held-out values landing inside the 95% band.

-53%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 →
0.47Projected 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 →
0.02–0.9195% 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 →
±55.9%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, Bufflehead in Prairie Potholes is projected to fall about 53% by 2029 — from 1.0 in 2024 to a central estimate of 0.47 (95% range 0.02–0.91). A 5-year backtest shows a typical error of ±55.9%, with 40% of held-out values landing inside the 95% band.19802029
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 →
20250.430.000.88
20260.440.000.89
20270.450.010.90
20280.460.010.91
20290.470.020.91

Routes In Prairie Potholes

Routes recording Bufflehead 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 →
Horsehead LkNORTH-DAKOTA552024
Wild RoseNORTH-DAKOTA62024
VirgelleMONTANA52023
Turtle MtnsNORTH-DAKOTA42024
WestbyMONTANA32019
DanzigNORTH-DAKOTA32010
CooperstownNORTH-DAKOTA32013
SunburstMONTANA21996
Lake GeorgeNORTH-DAKOTA22019
RollaNORTH-DAKOTA22024
Douglas CrkNORTH-DAKOTA22024
Sheyenne LkNORTH-DAKOTA22024
BraddockNORTH-DAKOTA12021
RoswellSOUTH-DAKOTA11998
BrittonSOUTH-DAKOTA12017

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