BirdAnalyst
Guild · New Hampshire · BBS 2025 Release · 1966–2024

Aerial Insectivores In New Hampshire

All statesNew Hampshire

18 species in this guild. As a group they are -54%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 →

guild collapsecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Aerial insectivores as a group have fallen sharply in New Hampshire, down 54% since 1968.

Aerial Insectivores In New Hampshire Population Forecast

If the recent trend holds, Aerial insectivores in New Hampshire is projected to fall about 33% by 2029 — from 2.3 in 2024 to a central estimate of 1.5 (95% range 0.59–2.5). A 5-year backtest shows a typical error of ±20.2%, with 100% of held-out values landing inside the 95% band.

-33%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 →
1.5Projected 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 →
0.59–2.595% 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 →
±20.2%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 New Hampshire is projected to fall about 33% by 2029 — from 2.3 in 2024 to a central estimate of 1.5 (95% range 0.59–2.5). A 5-year backtest shows a typical error of ±20.2%, 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 →
20251.80.852.7
20261.70.792.7
20271.70.722.6
20281.60.662.5
20291.50.592.5

Member Species In New Hampshire

Aerial insectivores species in New Hampshire.
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 →
Bank SwallowHirundinidae-97%
Cliff SwallowHirundinidae-93%
Olive-sided FlycatcherTyrannidae-90%
Yellow-bellied FlycatcherTyrannidae-82%
Eastern KingbirdTyrannidae-79%
Least FlycatcherTyrannidae-79%
Barn SwallowHirundinidae-77%
Northern Rough-winged SwallowHirundinidae-76%
Tree SwallowHirundinidae-69%
Chimney SwiftApodidae-62%
Common NighthawkCaprimulgidae-58%
Purple MartinHirundinidae-57%
Eastern Whip-poor-willCaprimulgidae-53%
Eastern Wood-PeweeTyrannidae+4%
Great Crested FlycatcherTyrannidae+4%
Alder FlycatcherTyrannidae+13%
Eastern PhoebeTyrannidae+30%
Willow FlycatcherTyrannidae+205%

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