BirdAnalyst
Species · BCR 24 · BBS 2025 Release · 1966–2024

Cerulean Warbler In Central Hardwoods

All regionsCentral HardwoodsForest birds

Cerulean Warbler in Central Hardwoods has fallen sharply: down 52% on the route-weighted index since 1968.

-52%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 →
84Routes 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 →

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 →

Cerulean Warbler has fallen sharply in Central Hardwoods: down 52% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Cerulean Warbler in Central Hardwoods is projected to stay roughly flat through 2029, near 0.14 (95% range 0.00–0.29). A 5-year backtest shows a typical error of ±38.3%, with 80% of held-out values landing inside the 95% band.

+4%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 →
0.14Projected 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 →
0.00–0.2995% 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 →
±38.3%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, Cerulean Warbler in Central Hardwoods is projected to stay roughly flat through 2029, near 0.14 (95% range 0.00–0.29). A 5-year backtest shows a typical error of ±38.3%, with 80% 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 →
20250.150.000.30
20260.150.000.30
20270.140.000.29
20280.140.000.29
20290.140.000.29

Routes In Central Hardwoods

Routes recording Cerulean Warbler in Central Hardwoods.
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 →
Levee 2KENTUCKY62019
ElkmontALABAMA31991
HoosierINDIANA32024
LeveeKENTUCKY31977
CentervilleMISSOURI32023
RomeOHIO32023
ComptonARKANSAS22022
RudyARKANSAS22021
CumbackINDIANA21996
VevayINDIANA22001
DrakesboroKENTUCKY21993
Mammoth CaveKENTUCKY22003
SwedenMISSOURI21986
SyracuseMISSOURI22007
MarshfieldMISSOURI22016
BaronOKLAHOMA21976
CollinwoodTENNESSEE22024
Lewis ForestTENNESSEE21988
Silver PtTENNESSEE22024
HillsboroALABAMA11988
Valhermoso SpgsALABAMA11969
RupertARKANSAS12023
LurtonARKANSAS12016
ZionARKANSAS12005
FultonARKANSAS11988

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