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

Smith's Longspur Population Trend in Alaska

All statesGeneralists

Smith's Longspur in Alaska has surged: up 12× on the route-weighted index since 1997.

12×Since 1997TrendPercent 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 →
5Routes 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 →
28YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Smith's Longspur Trends in AlaskaNotable 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 →

Smith's Longspur has surged in Alaska: up 12× on the route-weighted index since 1997.

Smith's Longspur Population Forecast in Alaska

If the recent trend holds, Smith's Longspur in Alaska is projected to fall about 49% by 2029 — from 0.95 in 2024 to a central estimate of 0.49 (95% range 0.08–0.90). A 5-year backtest shows a typical error of ±76.2%, with 20% of held-out values landing inside the 95% band.

-49%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 →
0.49Projected 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 →
0.08–0.9095% 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 →
±76.2%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, Smith's Longspur in Alaska is projected to fall about 49% by 2029 — from 0.95 in 2024 to a central estimate of 0.49 (95% range 0.08–0.90). A 5-year backtest shows a typical error of ±76.2%, with 20% of held-out values landing inside the 95% band.19832029
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 →
20250.430.020.84
20260.450.040.85
20270.460.050.87
20280.470.070.88
20290.490.080.90

Smith's Longspur Survey Routes in Alaska

Routes recording Smith's Longspur in Alaska.
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 →
Happy Valley5620241995
Galbraith L.820242006
Monahan319831983
Paxson Lake119971997
Nabesna Road119971997

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