BirdAnalyst
Species · BCR 12 · BBS 2025 Release · 1966–2024

Chimney Swift In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionAerial insectivores

Chimney Swift in Boreal Hardwood Transition has collapsed: down 79% on the route-weighted index since 1968.

-79%Since 1968
102Routes In Region
58Years

Notable Signals

long arc declinecomputed index

Chimney Swift has collapsed in Boreal Hardwood Transition: down 79% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Chimney Swift in Boreal Hardwood Transition is projected to fall about 82% by 2029 — from 0.52 in 2024 to a central estimate of 0.10 (95% range 0.00–0.93). A 5-year backtest shows a typical error of ±54%, with 100% of held-out values landing inside the 95% band.

-82%Change by 2029
0.10Projected 2029 index
0.00–0.9395% range
±54%Backtest error
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 index95% low95% high
20250.210.001.0
20260.180.001.0
20270.160.000.99
20280.130.000.96
20290.100.000.93

Routes In Boreal Hardwood Transition

Routes recording Chimney Swift in Boreal Hardwood Transition.
Lake CityMICHIGAN82022
Crystal FlsMICHIGAN72024
Rib LakeWISCONSIN72023
OntonagonMICHIGAN61985
MareniscoMICHIGAN62014
Traverse CtyMICHIGAN61992
Iron RiverWISCONSIN62024
GilmanWISCONSIN62024
Cass LakeMINNESOTA52012
Bear LakeMICHIGAN42015
FlambeauWISCONSIN42024
HermanMICHIGAN32015
Gibbs CityMICHIGAN32022
IshpemingMICHIGAN31990
ShingletonMICHIGAN32002
IsabellaMICHIGAN32004
Hubbard LakeMICHIGAN31996
HerronMICHIGAN32012
Imp LakeMICHIGAN32019
Wigwam BayMINNESOTA32018
BenaMINNESOTA31967
BemidjiMINNESOTA31968
DebsMINNESOTA32016
McgregorMINNESOTA32022
ExelandWISCONSIN32002

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