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

Thick-billed Longspur In Northern Rockies

All regionsNorthern RockiesGeneralists

Thick-billed Longspur in Northern Rockies has held roughly steady: up 1% on the route-weighted index since 1970.

+1%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 →
22Routes 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 →
55YearsYears 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 Thick-billed Longspur in Northern Rockies. See the full index history below.

Forecast

If the recent trend holds, Thick-billed Longspur in Northern Rockies is projected to fall about 20% by 2029 — from 0.72 in 2024 to a central estimate of 0.58 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±108.6%, with 60% of held-out values landing inside the 95% band.

-20%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 →
0.58Projected 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 →
0.00–1.395% 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 →
±108.6%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, Thick-billed Longspur in Northern Rockies is projected to fall about 20% by 2029 — from 0.72 in 2024 to a central estimate of 0.58 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±108.6%, 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 →
20250.590.001.3
20260.590.001.3
20270.580.001.3
20280.580.001.3
20290.580.001.3

Routes In Northern Rockies

Routes recording Thick-billed Longspur 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 →
ShirleyWYOMING652024
Rock RiverWYOMING602022
HarmonyWYOMING532023
AugustaMONTANA322024
SweetwaterWYOMING122009
OttoWYOMING61974
Twin BridgesMONTANA41976
ClarkWYOMING32024
St MaryMONTANA21977
BoulderMONTANA21998
LaurelMONTANA21988
Heart ButteMONTANA22024
Rock SpringsWYOMING21978
Patrick Draw 4WYOMING22002
Patrick Draw 5WYOMING22004
Willow CreekMONTANA11976
Willow Creek 2MONTANA12014
Patrick DrawWYOMING11980
RiversideWYOMING11971
Green RiverWYOMING11980
RelianceWYOMING11980
Patrick Draw 2WYOMING11982

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