BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Long-billed Curlew In Northern Rockies

All regionsNorthern RockiesShorebirds

Long-billed Curlew in Northern Rockies has surged: up 76% on the route-weighted index since 1970.

+76%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 →
78Routes 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 →
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 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 →

Long-billed Curlew has surged in Northern Rockies: up 76% on the route-weighted index since 1970.

Long-billed Curlew In Northern Rockies Population Forecast

If the recent trend holds, Long-billed Curlew in Northern Rockies is projected to stay roughly flat through 2029, near 1.2 (95% range 0.64–1.8). A 5-year backtest shows a typical error of ±15%, with 100% of held-out values landing inside the 95% band.

-2%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 →
1.2Projected 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 →
0.64–1.895% 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 →
±15%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 Northern Rockies is projected to stay roughly flat through 2029, near 1.2 (95% range 0.64–1.8). A 5-year backtest shows a typical error of ±15%, 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 →
20251.20.621.8
20261.20.631.8
20271.20.631.8
20281.20.631.8
20291.20.641.8

Routes In Northern Rockies

Routes recording Long-billed Curlew in Northern Rockies.
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 →
Big SandyWYOMING342024
Red RockMONTANA292023
Wolf CreekMONTANA282022
BoulderMONTANA262024
BeaverheadMONTANA182024
GlenMONTANA112024
RaynesfordMONTANA92024
RandolphUTAH92024
Sawtooth CtyIDAHO82014
LimaMONTANA82024
Muddy CreekMONTANA82015
Pryor Mtn.MONTANA82024
Brunzell SloughMONTANA72024
PolsonMONTANA62024
Heart ButteMONTANA62024
FontenelleWYOMING62024
Mtn ViewWYOMING51983
AugustaMONTANA42024
Pablo Res.MONTANA42017
St. Mary 2MONTANA42023
Fort LoganMONTANA42024
Summit PrOREGON42024
CabartonIDAHO32014
EllistonMONTANA32024
Freeman CreekMONTANA32016

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