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

Aerial Insectivores In Delaware

All statesDelaware

15 species in this guild. As a group they are +179%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 Delaware. See the full index history below.

Aerial Insectivores In Delaware Population Forecast

If the recent trend holds, Aerial insectivores in Delaware is projected to fall about 16% by 2029 — from 12 in 2024 to a central estimate of 9.9 (95% range 8.1–12). A 5-year backtest shows a typical error of ±15%, with 40% of held-out values landing inside the 95% band.

-16%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 →
9.9Projected 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 →
8.1–1295% 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 →
±15%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 Delaware is projected to fall about 16% by 2029 — from 12 in 2024 to a central estimate of 9.9 (95% range 8.1–12). A 5-year backtest shows a typical error of ±15%, with 40% 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 →
20259.47.611
20269.57.811
20279.77.911
20289.88.012
20299.98.112

Member Species In Delaware

Aerial insectivores species in Delaware.
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 →
Common NighthawkCaprimulgidae-89%
Eastern Whip-poor-willCaprimulgidae-86%
Eastern PhoebeTyrannidae-61%
Northern Rough-winged SwallowHirundinidae-60%
Chimney SwiftApodidae-41%
Bank SwallowHirundinidae+10%
Chuck-will's-widowCaprimulgidae+42%
Eastern KingbirdTyrannidae+45%
Willow FlycatcherTyrannidae+63%
Eastern Wood-PeweeTyrannidae+93%
Barn SwallowHirundinidae+96%
Great Crested FlycatcherTyrannidae+170%
Acadian FlycatcherTyrannidae+208%
Tree SwallowHirundinidae+729%
Purple MartinHirundinidae+962%

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