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

Forest Birds In Delaware

All statesDelaware

33 species in this guild. As a group they are +126%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 forest birds in Delaware. See the full index history below.

Forecast

If the recent trend holds, Forest birds in Delaware is projected to stay roughly flat through 2029, near 8.7 (95% range 6.7–11). A 5-year backtest shows a typical error of ±9.8%, with 60% of held-out values landing inside the 95% band.

+6%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 →
8.7Projected 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 →
6.7–1195% 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 →
±9.8%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, Forest birds in Delaware is projected to stay roughly flat through 2029, near 8.7 (95% range 6.7–11). A 5-year backtest shows a typical error of ±9.8%, with 60% 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 →
20258.46.410
20268.46.510
20278.56.610
20288.66.611
20298.76.711

Member Species In Delaware

Forest birds 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 →
Kentucky WarblerParulidae-80%
Prairie WarblerParulidae-63%
Yellow-throated VireoVireonidae-62%
American RedstartParulidae-57%
Black-and-white WarblerParulidae-44%
Warbling VireoVireonidae-41%
Hooded WarblerParulidae-24%
Wood ThrushTurdidae-12%
Yellow WarblerParulidae-11%
Louisiana WaterthrushParulidae-1%
Northern House WrenTroglodytidae+11%
White-eyed VireoVireonidae+31%
American RobinTurdidae+38%
Red-eyed VireoVireonidae+58%
Common YellowthroatParulidae+72%
Tufted TitmouseParidae+97%
Yellow-throated WarblerParulidae+107%
Red-bellied WoodpeckerPicidae+134%
Downy WoodpeckerPicidae+169%
OvenbirdParulidae+188%
Marsh WrenTroglodytidae+248%
Prothonotary WarblerParulidae+297%
Hairy WoodpeckerPicidae+314%
Red-headed WoodpeckerPicidae+324%
Carolina ChickadeeParidae+414%
Brown-headed NuthatchSittidae+428%
Pine WarblerParulidae+439%
Worm-eating WarblerParulidae+442%
White-breasted NuthatchSittidae+608%
Carolina WrenTroglodytidae13×
Blue-gray GnatcatcherPolioptilidae15×
Eastern BluebirdTurdidae24×
Pileated WoodpeckerPicidae42×

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