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Species · Montana · BBS 2025 Release · 1966–2024

Cassin's Kingbird Population Trend in Montana

All statesAerial insectivores

Cassin's Kingbird in Montana has fallen sharply: down 66% on the route-weighted index since 1981.

-66%Since 1981TrendPercent 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 →
25YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Cassin's Kingbird Trends in MontanaNotable 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 declinecomputed 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 →

Cassin's Kingbird has fallen sharply in Montana: down 66% on the route-weighted index since 1981.

Cassin's Kingbird Population Forecast in Montana

If the recent trend holds, Cassin's Kingbird in Montana is projected to stay roughly flat through 2029, near 0.10 (95% range 0.00–0.40). A 5-year backtest shows a typical error of ±508.4%, with 100% 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 →
0.10Projected 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 →
0.00–0.4095% 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 →
±508.4%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, Cassin's Kingbird in Montana is projected to stay roughly flat through 2029, near 0.10 (95% range 0.00–0.40). A 5-year backtest shows a typical error of ±508.4%, with 100% 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 →
20250.110.000.41
20260.110.000.41
20270.110.000.40
20280.100.000.40
20290.100.000.40

Cassin's Kingbird Survey Routes in Montana

Routes recording Cassin's Kingbird in Montana.
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 →
Miles City820222022
Brandenberg520191979
Maynard Coulee220242024
Bull Mtn.220211995
Chuffey Spring220232023

Cassin's Kingbird Population Trend in Other States

arizonacaliforniacoloradokansasnebraskanevadanew-mexicooklahomasouth-dakotatexasutahwyoming

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