BirdAnalyst
Guild · Michigan · BBS 2026 Release · 1966–2025

Wetland Birds In Michigan

All statesMichigan

20 species in this guild. As a group they are -55%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 →

Wetland birds as a group have fallen sharply in Michigan, down 55% since 1968.

Wetland Birds In Michigan Population Forecast

If the recent trend holds, Wetland birds in Michigan is projected to fall about 38% by 2030 — from 4.8 in 2025 to a central estimate of 3.0 (95% range 0.87–5.1). A 5-year backtest shows a typical error of ±25.7%, with 100% of held-out values landing inside the 95% band.

-38%Change by 2030TrendPercent 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 →
3.0Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.87–5.195% 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 →
±25.7%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 Michigan is projected to fall about 38% by 2030 — from 4.8 in 2025 to a central estimate of 3.0 (95% range 0.87–5.1). A 5-year backtest shows a typical error of ±25.7%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20263.41.35.5
20273.31.25.4
20283.21.15.3
20293.10.975.2
20303.00.875.1

Member Species In Michigan

Wetland birds species in Michigan.
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 →
Herring GullLaridae-96%
Black TernLaridae-96%
Pied-billed GrebePodicipedidae-95%
Common GallinuleRallidae-86%
SoraRallidae-82%
Virginia RailRallidae-63%
Double-crested CormorantPhalacrocoracidae-63%
American CootRallidae-60%
Red-winged BlackbirdIcteridae-54%
Least BitternArdeidae-53%
Caspian TernLaridae-33%
Belted KingfisherAlcedinidae-9%
American BitternArdeidae+63%
Green HeronArdeidae+69%
Great EgretArdeidae+77%
Great Blue HeronArdeidae+101%
Common LoonGaviidae+149%
Swamp SparrowPasserellidae+445%
Sandhill CraneGruidae41×
Ring-billed GullLaridae47×

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.