BirdAnalyst
Species · Montana · BBS 2025 Release · 1966–2024

Wilson's Phalarope Population Trend in Montana

All statesShorebirds

Wilson's Phalarope in Montana has edged up: up 20% on the route-weighted index since 1970.

+20%Since 1970TrendPercent 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 →
66Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Wilson's Phalarope Trends in MontanaNotable 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 Wilson's Phalarope in Montana. See the full index history below.

Wilson's Phalarope Population Forecast in Montana

If the recent trend holds, Wilson's Phalarope in Montana is projected to stay roughly flat through 2029, near 1.7 (95% range 0.04–3.3). A 5-year backtest shows a typical error of ±84.8%, with 100% of held-out values landing inside the 95% band.

-7%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 →
1.7Projected 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 →
0.04–3.395% 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 →
±84.8%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, Wilson's Phalarope in Montana is projected to stay roughly flat through 2029, near 1.7 (95% range 0.04–3.3). A 5-year backtest shows a typical error of ±84.8%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20251.60.023.3
20261.70.033.3
20271.70.033.3
20281.70.043.3
20291.70.043.3

Wilson's Phalarope Survey Routes in Montana

Routes recording Wilson's Phalarope in Montana.
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 →
Shawmut4420241979
Highwood4120241968
Malta2020231975
Wheat Basin1720242018
Sunburst920071968
Dinosaurs H.M.920212019
Roundup920182018
Glentana820242015
Harlem720211968
Roy720241989
Ingomar720231976
Ester Lake720242015
Beaverhead620171973
Saco620242015
St Xavier519921983
Gildford520232016
Polson419971992
Shelby420242015
Lambert420232022
Virgelle320241979
Augusta320211978
Powderville320231972
Albion320191982
East Glacier Park320212018
Coleman Coulee320232018

Wilson's Phalarope Population Trend in Other States

californiacoloradoidahoillinoisiowakansasminnesotanebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwashingtonwisconsinwyoming

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