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Species · Kansas · BBS 2025 Release · 1966–2024

Cassin's Sparrow Population Trend in Kansas

All statesGrassland birds

Cassin's Sparrow in Kansas has collapsed: down 78% on the route-weighted index since 1970.

-78%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 →
26Routes 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 →
56YearsYears 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 Sparrow Trends in KansasNotable 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 Sparrow has collapsed in Kansas: down 78% on the route-weighted index since 1970.

Cassin's Sparrow Population Forecast in Kansas

If the recent trend holds, Cassin's Sparrow in Kansas is projected to rise about 12% by 2029 — from 0.15 in 2024 to a central estimate of 0.17 (95% range 0.00–3.4). A 5-year backtest shows a typical error of ±208.4%, with 100% of held-out values landing inside the 95% band.

+12%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 →
0.17Projected 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 →
0.00–3.495% 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 →
±208.4%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 Sparrow in Kansas is projected to rise about 12% by 2029 — from 0.15 in 2024 to a central estimate of 0.17 (95% range 0.00–3.4). A 5-year backtest shows a typical error of ±208.4%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.350.003.6
20260.310.003.6
20270.260.003.5
20280.220.003.5
20290.170.003.4

Cassin's Sparrow Survey Routes in Kansas

Routes recording Cassin's Sparrow in Kansas.
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 →
Ashland2120211971
Coldwater1620111976
Hopewell720112003
Ulysses620222000
Grigston620172002
Lakin520171967
Plymell420242000
Hays320111974
Gove320221980
Ash Valley320142002
St John220141974
Albert219831983
Gray219781977
Leoville220111989
Leoti220222000
Coats120221974
Kanopolis120132013
Wallace120181967
Minneapolis119741974
Phillipsburg119791979
Missler120151975
Ruleton120181991
Berwet120122011
Lincolnville120112011
Rexford120222011

Cassin's Sparrow Population Trend in Other States

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