Species · Colorado · BBS 2025 Release · 1966–2024

Chimney Swift Population Trend in Colorado

Chimney Swift in Colorado has collapsed: down 82% on the route-weighted index since 1970.

-82%Since 1970
8Routes In State
51Years

Notable Chimney Swift Trends in Colorado

long arc declinecomputed index

Chimney Swift has collapsed in Colorado: down 82% on the route-weighted index since 1970.

Chimney Swift Population Forecast in Colorado

If the recent trend holds, Chimney Swift in Colorado is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.17). A 5-year backtest shows a typical error of ±108.7%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2028
0.00Projected 2028 index
0.000.1795% range
±108.7%Backtest error
19682028
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
20240.000.000.17
20250.000.000.17
20260.000.000.17
20270.000.000.17
20280.000.000.17

Chimney Swift Survey Routes in Colorado

Routes recording Chimney Swift in Colorado.
Burlington620142004
Fleming320231968
Amherst220211993
Julesburg220191998
Waverly120182015
Fort Morgan120231998
Flagler120211997
Ellicott120102010

Chimney Swift Population Trend in Other States

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