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

Wetland Birds In Washington

All statesWashington

23 species in this guild. As a group they are -73%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 →

Wetland birds as a group have fallen sharply in Washington, down 73% since 1970.

Wetland Birds In Washington Population Forecast

If the recent trend holds, Wetland birds in Washington is projected to fall about 78% by 2029 — from 0.37 in 2024 to a central estimate of 0.08 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±31.2%, with 100% of held-out values landing inside the 95% band.

-78%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 →
0.08Projected 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 →
0.00–1.195% 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 →
±31.2%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, Wetland birds in Washington is projected to fall about 78% by 2029 — from 0.37 in 2024 to a central estimate of 0.08 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±31.2%, 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 →
20250.210.001.3
20260.180.001.2
20270.150.001.2
20280.120.001.2
20290.080.001.1

Member Species In Washington

Wetland birds species in Washington.
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 →
Black-crowned Night HeronArdeidae-95%
Western GullLaridae-94%
Eared GrebePodicipedidae-87%
Ring-billed GullLaridae-76%
Green HeronArdeidae-73%
Red-necked GrebePodicipedidae-72%
Glaucous-winged GullLaridae-71%
Pied-billed GrebePodicipedidae-65%
American BitternArdeidae-64%
Forster's TernLaridae-64%
Virginia RailRallidae-63%
Western GrebePodicipedidae-61%
American CootRallidae-55%
Black TernLaridae-53%
Pelagic CormorantPhalacrocoracidae-53%
Great Blue HeronArdeidae-46%
SoraRallidae-45%
Common LoonGaviidae-11%
Caspian TernLaridae-11%
Double-crested CormorantPhalacrocoracidae-7%
American White PelicanPelecanidae-0%
California GullLaridae+61%
Great EgretArdeidae+179%

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