BirdAnalyst
Species · South Dakota · BBS 2026 Release · 1966–2025

Long-billed Curlew Population Trend in South Dakota

All statesShorebirds

Long-billed Curlew in South Dakota has increased: up 41% on the route-weighted index since 1969.

+41%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 →
28Routes 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 →
58YearsYears 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 South DakotaNotable 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 Long-billed Curlew in South Dakota. See the full index history below.

Long-billed Curlew Population Forecast in South Dakota

If the recent trend holds, Long-billed Curlew in South Dakota is projected to rise about 261% by 2030 — from 0.32 in 2025 to a central estimate of 1.2 (95% range 0.40–1.9). A 5-year backtest shows a typical error of ±66.8%, with 80% of held-out values landing inside the 95% band.

+261%Change by 2030TrendPercent 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 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.40–1.995% 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 →
±66.8%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, Long-billed Curlew in South Dakota is projected to rise about 261% by 2030 — from 0.32 in 2025 to a central estimate of 1.2 (95% range 0.40–1.9). A 5-year backtest shows a typical error of ±66.8%, with 80% of held-out values landing inside the 95% band.19672030
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 →
20261.10.381.9
20271.10.381.9
20281.10.391.9
20291.20.391.9
20301.20.401.9

Long-billed Curlew Survey Routes in South Dakota

Routes recording Long-billed Curlew in South Dakota.
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 →
S. Pioneer1320241994
Pioneer920241992
Cedar Pass620171967
Cottonwood420251995
Rosebud420111967
Hayes420241992
French Creek320051998
Owanka319961967
Fort Pierre320251969
Ardmore320191977
Badlands320231983
White River320122012
Indian220241994
Railroad Butte220181997
Volunteer220171967
Maurine219711969
Eagle Butte220152001
Marcus220131999
Winner120092009
Rockyford120062006
Wind Cave Np120132005
Laplant120091977
Promise119991987
Ottumwa120221967
Harding120171967

Long-billed Curlew Population Trend in Other States

californiacoloradoidahokansasmontananebraskanevadanew-mexiconorth-dakotaoklahomaoregontexasutahwashingtonwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.