BirdAnalyst
Species · BCR 22 · BBS 2025 Release · 1966–2024

Prothonotary Warbler In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieForest birds

Prothonotary Warbler in Eastern Tallgrass Prairie has surged: up 116% on the route-weighted index since 1968.

+116%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 →
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 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 →

Prothonotary Warbler has surged in Eastern Tallgrass Prairie: up 116% on the route-weighted index since 1968.

Prothonotary Warbler In Eastern Tallgrass Prairie Population Forecast

If the recent trend holds, Prothonotary Warbler in Eastern Tallgrass Prairie is projected to rise about 32% by 2029 — from 0.06 in 2024 to a central estimate of 0.08 (95% range 0.04–0.13). A 5-year backtest shows a typical error of ±32.1%, with 100% of held-out values landing inside the 95% band.

+32%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 →
0.08Projected 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 →
0.04–0.1395% 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 →
±32.1%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 rise about 32% by 2029 — from 0.06 in 2024 to a central estimate of 0.08 (95% range 0.04–0.13). A 5-year backtest shows a typical error of ±32.1%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.080.040.13
20260.080.040.13
20270.080.040.13
20280.080.040.13
20290.080.040.13

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 →
BelleviewILLINOIS52024
EldredILLINOIS31995
Trading PostKANSAS32024
NewarkILLINOIS22014
Mascoutah LkILLINOIS22023
MoreheadKANSAS22023
FilleyMISSOURI22022
StetMISSOURI21995
EnonOHIO22021
GeneseoILLINOIS12018
GulfportILLINOIS12023
ChandlervillILLINOIS11973
AthensvilleILLINOIS12003
ConcordILLINOIS12004
PawneeILLINOIS12002
FairlandILLINOIS11994
HumboldtILLINOIS12023
ColumbiaILLINOIS11968
JamestownILLINOIS12012
St MorganILLINOIS12022
BeaucoupILLINOIS12023
OlneyILLINOIS12024
FloraILLINOIS12017
RobinsonILLINOIS12022
Camp PointILLINOIS12023

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