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

Long-billed Curlew Population Trend in Montana

All statesShorebirds

Long-billed Curlew in Montana has surged: up 407% on the route-weighted index since 1970.

+407%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 →
77Routes 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 Long-billed Curlew 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 →

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 →

Long-billed Curlew has surged in Montana: up 407% on the route-weighted index since 1970.

Long-billed Curlew Population Forecast in Montana

If the recent trend holds, Long-billed Curlew in Montana is projected to stay roughly flat through 2029, near 4.0 (95% range 2.4–5.6). A 5-year backtest shows a typical error of ±29.7%, with 60% of held-out values landing inside the 95% band.

-5%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 →
4.0Projected 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 →
2.4–5.695% 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 →
±29.7%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, Long-billed Curlew in Montana is projected to stay roughly flat through 2029, near 4.0 (95% range 2.4–5.6). A 5-year backtest shows a typical error of ±29.7%, with 60% 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 →
20253.82.25.5
20263.92.35.5
20273.92.35.5
20284.02.35.6
20294.02.45.6

Long-billed Curlew Survey Routes in Montana

Routes recording Long-billed Curlew 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 →
Roundup3120242016
Red Rock2920231973
Wolf Creek2820222015
Boulder2620241969
Winifred 22420242024
Wheat Basin2220242017
Beaverhead1820241973
Gildford1720242015
Shawmut1420241979
Winifred1420232023
Leroy1320241991
Two Dot1320241976
Virgelle1220241979
Redstone1120241968
Glen1120241977
Maynard Coulee1120242017
Roy1020241991
Flatwillow1020081968
Ester Lake920242015
Raynesford920242016
Winnett920232017
Lima820241995
Flatwillow 2820232010
Muddy Creek820152015
Pryor Mtn.820242001

Long-billed Curlew Population Trend in Other States

californiacoloradoidahokansasnebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwashingtonwyoming

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