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

Forest Birds In Idaho

All statesIdaho

46 species in this guild. As a group they are -58%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 1970.

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 →

Forest birds as a group have fallen sharply in Idaho, down 58% since 1970.

Forest Birds In Idaho Population Forecast

If the recent trend holds, Forest birds in Idaho is projected to fall about 24% by 2029 — from 2.1 in 2024 to a central estimate of 1.6 (95% range 0.00–4.0). A 5-year backtest shows a typical error of ±43.3%, with 100% of held-out values landing inside the 95% band.

-24%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 →
1.6Projected 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 →
0.00–4.095% 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 →
±43.3%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 Idaho is projected to fall about 24% by 2029 — from 2.1 in 2024 to a central estimate of 1.6 (95% range 0.00–4.0). A 5-year backtest shows a typical error of ±43.3%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20251.70.004.1
20261.70.004.0
20271.60.004.0
20281.60.004.0
20291.60.004.0

Member Species In Idaho

Forest birds species in Idaho.
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 →
White-breasted NuthatchSittidae-91%
Plumbeous VireoVireonidae-88%
Juniper TitmouseParidae-82%
Canyon WrenTroglodytidae-78%
Pygmy NuthatchSittidae-75%
American RedstartParulidae-71%
Black-backed WoodpeckerPicidae-64%
Downy WoodpeckerPicidae-62%
Marsh WrenTroglodytidae-53%
Hairy WoodpeckerPicidae-47%
Brown CreeperCerthiidae-46%
American RobinTurdidae-30%
Northern WaterthrushParulidae-28%
American Three-toed WoodpeckerPicidae-25%
Blue-gray GnatcatcherPolioptilidae-24%
Western BluebirdTurdidae-21%
Townsend's SolitaireTurdidae-19%
Mountain BluebirdTurdidae-14%
Williamson's SapsuckerPicidae-11%
Varied ThrushTurdidae-10%
Black-throated Gray WarblerParulidae-6%
Black-capped ChickadeeParidae-5%
VeeryTurdidae+17%
Mountain ChickadeeParidae+27%
Yellow WarblerParulidae+32%
Hermit ThrushTurdidae+47%
Red-naped SapsuckerPicidae+79%
Lewis's WoodpeckerPicidae+79%
MacGillivray's WarblerParulidae+96%
Swainson's ThrushTurdidae+133%
Warbling VireoVireonidae+135%
Red-eyed VireoVireonidae+148%
Wilson's WarblerParulidae+152%
Cassin's VireoVireonidae+166%
Pileated WoodpeckerPicidae+166%
Nashville WarblerParulidae+183%
Orange-crowned WarblerParulidae+204%
Chestnut-backed ChickadeeParidae+207%
Ruby-crowned KingletRegulidae+249%
Common YellowthroatParulidae+262%
Rock WrenTroglodytidae+375%
Red-breasted NuthatchSittidae+448%
Northern House WrenTroglodytidae+483%
Pacific WrenTroglodytidae+583%
Townsend's WarblerParulidae+770%
Golden-crowned KingletRegulidae+832%

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