BirdAnalyst
Species · BCR 22 · BBS 2026 Release · 1966–2025

Prothonotary Warbler In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieForest birds

Prothonotary Warbler in Eastern Tallgrass Prairie has surged: up 134% on the route-weighted index since 1968.

+134%Since 1968TrendPercent 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 →
64Routes 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 →
58YearsYears 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 →

No notable trend signals for Prothonotary Warbler in Eastern Tallgrass Prairie. See the full index history below.

Prothonotary Warbler In Eastern Tallgrass Prairie Population Forecast

If the recent trend holds, Prothonotary Warbler in Eastern Tallgrass Prairie is projected to fall about 11% by 2030 — from 0.10 in 2025 to a central estimate of 0.09 (95% range 0.04–0.13). A 5-year backtest shows a typical error of ±20.5%, with 100% of held-out values landing inside the 95% band.

-11%Change by 2030TrendPercent 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 →
0.09Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.04–0.1395% 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 →
±20.5%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, Prothonotary Warbler in Eastern Tallgrass Prairie is projected to fall about 11% by 2030 — from 0.10 in 2025 to a central estimate of 0.09 (95% range 0.04–0.13). A 5-year backtest shows a typical error of ±20.5%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.080.040.13
20270.080.040.13
20280.080.040.13
20290.080.040.13
20300.090.040.13

Routes In Eastern Tallgrass Prairie

Routes recording Prothonotary Warbler in Eastern Tallgrass 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 →
BelleviewILLINOIS62025
EldredILLINOIS31995
NewarkILLINOIS22014
Mascoutah LkILLINOIS22023
BeaucoupILLINOIS22025
FilleyMISSOURI22025
StetMISSOURI21995
EnonOHIO22021
GeneseoILLINOIS12025
GulfportILLINOIS12023
ChandlervillILLINOIS11973
AthensvilleILLINOIS12003
ConcordILLINOIS12004
PawneeILLINOIS12002
FairlandILLINOIS11994
HumboldtILLINOIS12023
ColumbiaILLINOIS11968
JamestownILLINOIS12025
St MorganILLINOIS12022
OlneyILLINOIS12024
FloraILLINOIS12017
RobinsonILLINOIS12022
Camp PointILLINOIS12025
DarmstadtILLINOIS12012
Lake SummersetILLINOIS12025

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.