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

Aerial Insectivores In Connecticut

All statesConnecticut

16 species in this guild. As a group they are -29%Guild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology → since 1968.

Guild SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for aerial insectivores in Connecticut. See the full index history below.

Aerial Insectivores In Connecticut Population Forecast

If the recent trend holds, Aerial insectivores in Connecticut is projected to stay roughly flat through 2029, near 3.0 (95% range 1.9–4.1). A 5-year backtest shows a typical error of ±17.8%, with 100% 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 →
3.0Projected 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 →
1.9–4.195% 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 →
±17.8%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, Aerial insectivores in Connecticut is projected to stay roughly flat through 2029, near 3.0 (95% range 1.9–4.1). A 5-year backtest shows a typical error of ±17.8%, with 100% 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 →
20253.11.94.2
20263.01.94.2
20273.01.94.1
20283.01.94.1
20293.01.94.1

Member Species In Connecticut

Aerial insectivores species in Connecticut.
TrendPercent 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 →
Least FlycatcherTyrannidae-84%
Eastern KingbirdTyrannidae-79%
Eastern Whip-poor-willCaprimulgidae-64%
Cliff SwallowHirundinidae-42%
Purple MartinHirundinidae-22%
Tree SwallowHirundinidae+13%
Eastern PhoebeTyrannidae+16%
Barn SwallowHirundinidae+18%
Great Crested FlycatcherTyrannidae+28%
Willow FlycatcherTyrannidae+30%
Eastern Wood-PeweeTyrannidae+31%
Chimney SwiftApodidae+34%
Alder FlycatcherTyrannidae+66%
Bank SwallowHirundinidae+77%
Acadian FlycatcherTyrannidae+121%
Northern Rough-winged SwallowHirundinidae+295%

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