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

Brown Thrasher Population Trend in Kansas

All statesGeneralists

Brown Thrasher in Kansas has declined: down 43% on the route-weighted index since 1969.

-43%Since 1969TrendPercent 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 →
67Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Brown Thrasher 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 →

No notable trend signals for Brown Thrasher in Kansas. See the full index history below.

Brown Thrasher Population Forecast in Kansas

If the recent trend holds, Brown Thrasher in Kansas is projected to fall about 15% by 2029 — from 6.5 in 2024 to a central estimate of 5.6 (95% range 3.4–7.7). A 5-year backtest shows a typical error of ±15.5%, with 100% of held-out values landing inside the 95% band.

-15%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 →
5.6Projected 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 →
3.4–7.795% 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 →
±15.5%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, Brown Thrasher in Kansas is projected to fall about 15% by 2029 — from 6.5 in 2024 to a central estimate of 5.6 (95% range 3.4–7.7). A 5-year backtest shows a typical error of ±15.5%, 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 →
20256.03.88.1
20265.93.78.0
20275.83.67.9
20285.73.57.8
20295.63.47.7

Brown Thrasher Survey Routes in Kansas

Routes recording Brown Thrasher 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 →
Covert3820241967
Kanopolis2020241967
Jewell2020051967
Beloit1920032000
Phillipsburg1720221967
Hanover1620231969
Logan1620221967
Grantville1520221967
Lincolnville1520242002
Chapman1419811967
Berwet1420242000
Beloit 21320182005
Jewell 21220242006
Solomon1120191982
Hollenberg1020231969
Trading Post1020242000
St John820191967
Minneapolis820191967
Jamestown820242000
Albert720241967
Goessel720242000
Damar720162000
Gray620191967
Pittsburg620212000
Morehead620242000

Brown Thrasher Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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