BirdAnalyst
Species · BCR 24 · BBS 2026 Release · 1966–2025

Chimney Swift In Central Hardwoods

All regionsCentral HardwoodsAerial insectivores

Chimney Swift in Central Hardwoods has collapsed: down 84% on the route-weighted index since 1968.

-84%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 →
162Routes 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 →
59YearsYears 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 →

Chimney Swift has collapsed in Central Hardwoods: down 84% on the route-weighted index since 1968.

Chimney Swift In Central Hardwoods Population Forecast

If the recent trend holds, Chimney Swift in Central Hardwoods is projected to fall about 85% by 2030 — from 3.2 in 2025 to a central estimate of 0.47 (95% range 0.00–4.7). A 5-year backtest shows a typical error of ±24.9%, with 100% of held-out values landing inside the 95% band.

-85%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 →
0.47Projected 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 →
0.00–4.795% 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 →
±24.9%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, Chimney Swift in Central Hardwoods is projected to fall about 85% by 2030 — from 3.2 in 2025 to a central estimate of 0.47 (95% range 0.00–4.7). A 5-year backtest shows a typical error of ±24.9%, 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 →
20261.70.005.9
20271.40.005.6
20281.10.005.3
20290.790.005.0
20300.470.004.7

Routes In Central Hardwoods

Routes recording Chimney Swift 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 →
FarwellARKANSAS932018
MillionKENTUCKY501986
Cole CampMISSOURI441990
LeveeKENTUCKY301982
Daniel BooneKENTUCKY261988
GoshenKENTUCKY241999
BoxvilleKENTUCKY191983
Buena VistaKENTUCKY192017
DelwoodILLINOIS172025
Indian SpgsINDIANA172025
GlencoeKENTUCKY172018
SyracuseMISSOURI172023
CelestineINDIANA162025
Iron BridgeKENTUCKY161998
AzaliaINDIANA152025
GraydonMISSOURI152022
PeytonsvilleTENNESSEE152025
EvansvilleINDIANA142019
GeorgiaINDIANA122025
DixieKENTUCKY122019
DixonKENTUCKY122022
PorterKENTUCKY112025
Valhermoso SpgsALABAMA102010
BremenILLINOIS102025
Levee 2KENTUCKY102019

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