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

Bewick's Wren In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieForest birds

Bewick's Wren in Eastern Tallgrass Prairie has fallen sharply: down 55% on the route-weighted index since 1968.

-55%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 →
42Routes 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 →
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 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 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 →

Bewick's Wren has fallen sharply in Eastern Tallgrass Prairie: down 55% on the route-weighted index since 1968.

Bewick's Wren In Eastern Tallgrass Prairie Population Forecast

If the recent trend holds, Bewick's Wren in Eastern Tallgrass Prairie is projected to stay roughly flat through 2029, near 0.05 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±340%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.05Projected 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 →
0.00–0.1295% 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 →
±340%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, Bewick's Wren in Eastern Tallgrass Prairie is projected to stay roughly flat through 2029, near 0.05 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±340%, 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 →
20250.050.000.13
20260.050.000.13
20270.050.000.13
20280.050.000.12
20290.050.000.12

Routes In Eastern Tallgrass Prairie

Routes recording Bewick's Wren 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 →
TrentonMISSOURI41967
FilleyMISSOURI32024
UnionMISSOURI31999
LincolnvilleKANSAS22023
WashingtonMISSOURI21976
OhioMISSOURI22006
WatsonMISSOURI22021
ConcordILLINOIS11991
ColumbiaILLINOIS11966
EubanksILLINOIS12015
Mt HamillIOWA12017
HumboldtKANSAS11991
LaplandKANSAS12017
DoverKANSAS11998
BarclayKANSAS11999
WrefordKANSAS12023
EllinorKANSAS12007
LongtonKANSAS12019
ReeceKANSAS12024
Le LoupKANSAS12018
OlsburgKANSAS12023
RensselaerMISSOURI11975
WarrenMISSOURI11969
MadisonMISSOURI12005
HuntsvilleMISSOURI12022

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