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

Marbled Godwit In Northern Rockies

All regionsNorthern RockiesShorebirds

Marbled Godwit in Northern Rockies has increased: up 37% on the route-weighted index since 1983.

+37%Since 1983TrendPercent 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 →
8Routes 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 →
29YearsYears 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 Marbled Godwit in Northern Rockies. See the full index history below.

Forecast

If the recent trend holds, Marbled Godwit in Northern Rockies is projected to stay roughly flat through 2029, near 0.04 (95% range 0.01–0.08). A 5-year backtest shows a typical error of ±44.2%, with 80% of held-out values landing inside the 95% band.

n/aChange 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 →
0.04Projected 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 →
0.01–0.0895% 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 →
±44.2%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, Marbled Godwit in Northern Rockies is projected to stay roughly flat through 2029, near 0.04 (95% range 0.01–0.08). A 5-year backtest shows a typical error of ±44.2%, with 80% of held-out values landing inside the 95% band.19792029
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 →
20250.040.010.08
20260.040.010.08
20270.040.010.08
20280.040.010.08
20290.040.010.08

Routes In Northern Rockies

Routes recording Marbled Godwit 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 →
AugustaMONTANA32021
BeaverheadMONTANA21997
St. Mary 2MONTANA22022
Heart ButteMONTANA22024
RaynesfordMONTANA22023
St MaryMONTANA11989
Red RockMONTANA12023
Willow Creek 2MONTANA12024

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