BirdAnalyst
Species · BCR 19 · BBS 2025 Release · 1966–2024

American Bittern In Central Mixed Grass Prairie

All regionsCentral Mixed Grass PrairieWetland birds

American Bittern in Central Mixed Grass Prairie has surged: up 545% on the route-weighted index since 1972.

+545%Since 1972TrendPercent 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 →
17Routes 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 →
51YearsYears 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 →

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 →

American Bittern has surged in Central Mixed Grass Prairie: up 545% on the route-weighted index since 1972.

American Bittern In Central Mixed Grass Prairie Population Forecast

If the recent trend holds, American Bittern in Central Mixed Grass Prairie is projected to fall about 19% by 2029 — from 0.27 in 2024 to a central estimate of 0.22 (95% range 0.01–0.42). A 5-year backtest shows a typical error of ±48.3%, with 100% of held-out values landing inside the 95% band.

-19%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 →
0.22Projected 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 →
0.01–0.4295% 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 →
±48.3%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, American Bittern in Central Mixed Grass Prairie is projected to fall about 19% by 2029 — from 0.27 in 2024 to a central estimate of 0.22 (95% range 0.01–0.42). A 5-year backtest shows a typical error of ±48.3%, 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 →
20250.210.000.41
20260.210.010.41
20270.210.010.42
20280.210.010.42
20290.220.010.42

Routes In Central Mixed Grass Prairie

Routes recording American Bittern in Central Mixed Grass Prairie.
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 →
Wheeler CoNEBRASKA82024
BassettNEBRASKA62024
AlbertKANSAS42019
DouglasOKLAHOMA41987
GrayKANSAS31994
KennedyNEBRASKA32024
Crescent LkNEBRASKA32016
Swan LakeNEBRASKA22022
CoatsKANSAS11979
BuckeyeKANSAS11974
KearneyNEBRASKA11974
SurpriseNEBRASKA11972
Piester LakeNEBRASKA12023
BrownleeNEBRASKA12024
MullenNEBRASKA12017
NenzelNEBRASKA12022
JetOKLAHOMA12016

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