BirdAnalyst
Species · Connecticut · BBS 2025 Release · 1966–2024

Cliff Swallow Population Trend in Connecticut

All statesAerial insectivores

Cliff Swallow in Connecticut has declined: down 42% on the route-weighted index since 1976.

-42%Since 1976
8Routes In State
24Years

Notable Cliff Swallow Trends in Connecticut

No notable trend signals for Cliff Swallow in Connecticut. See the full index history below.

Cliff Swallow Population Forecast in Connecticut

If the recent trend holds, Cliff Swallow in Connecticut is projected to rise about 129% by 2026 — from 0.09 in 2021 to a central estimate of 0.21 (95% range 0.00–0.73). A 5-year backtest shows a typical error of ±100.9%, with 60% of held-out values landing inside the 95% band.

+129%Change by 2026
0.21Projected 2026 index
0.00–0.7395% range
±100.9%Backtest error
19732026
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
20220.220.000.74
20230.220.000.74
20240.210.000.74
20250.210.000.73
20260.210.000.73

Cliff Swallow Survey Routes in Connecticut

Routes recording Cliff Swallow in Connecticut.
Warren720042004
New Hartford419871975
Danbury220082008
Sherman120051973
Long Hill120192005
Mid Haddam119861981
Warren 2120212021
Granby119911990

Cliff Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradodelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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