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

Black-billed Magpie In Prairie Potholes

All regionsPrairie PotholesGeneralists

Black-billed Magpie in Prairie Potholes has edged up: up 20% on the route-weighted index since 1969.

+20%Since 1969TrendPercent 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 →
50Routes 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 →

No notable trend signals for Black-billed Magpie in Prairie Potholes. See the full index history below.

Black-billed Magpie In Prairie Potholes Population Forecast

If the recent trend holds, Black-billed Magpie in Prairie Potholes is projected to fall about 27% by 2029 — from 1.4 in 2024 to a central estimate of 1.00 (95% range 0.41–1.6). A 5-year backtest shows a typical error of ±21.1%, with 100% of held-out values landing inside the 95% band.

-27%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 →
1.00Projected 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 →
0.41–1.695% 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 →
±21.1%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, Black-billed Magpie in Prairie Potholes is projected to fall about 27% by 2029 — from 1.4 in 2024 to a central estimate of 1.00 (95% range 0.41–1.6). A 5-year backtest shows a typical error of ±21.1%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.980.391.6
20260.980.391.6
20270.990.401.6
20280.990.401.6
20291.000.411.6

Routes In Prairie Potholes

Routes recording Black-billed Magpie 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 →
RedstoneMONTANA352024
ErieMINNESOTA252017
ClevelandMONTANA222024
Hay LakeMONTANA142022
WylieMINNESOTA102024
Lake BronsonMINNESOTA102011
WhitlashMONTANA92024
Turtle MtnsNORTH-DAKOTA72024
HarlemMONTANA62021
StanleyNORTH-DAKOTA62021
OkleeMINNESOTA52021
GryglaMINNESOTA52017
BadgerMINNESOTA52018
ChinookMONTANA32024
CarpioNORTH-DAKOTA32023
DenbighNORTH-DAKOTA32023
Wild RoseNORTH-DAKOTA32008
VeblenSOUTH-DAKOTA31970
GlasgowMONTANA22023
Great FallsMONTANA22024
Wolf PointMONTANA22024
Sun RiverMONTANA22024
MidwayNEBRASKA21995
EmeradoNORTH-DAKOTA22018
RollaNORTH-DAKOTA22022

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