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

Game Birds In Iowa

All statesIowa

4 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 1969.

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 →

Game birds as a group have fallen sharply in Iowa, down 58% since 1969.

Forecast

If the recent trend holds, Game birds in Iowa is projected to fall about 44% by 2029 — from 4.8 in 2024 to a central estimate of 2.7 (95% range 0.00–8.2). A 5-year backtest shows a typical error of ±45.1%, with 100% of held-out values landing inside the 95% band.

-44%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 →
2.7Projected 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 →
0.00–8.295% 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 →
±45.1%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, Game birds in Iowa is projected to fall about 44% by 2029 — from 4.8 in 2024 to a central estimate of 2.7 (95% range 0.00–8.2). A 5-year backtest shows a typical error of ±45.1%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20253.50.009.0
20263.30.008.8
20273.10.008.6
20282.90.008.4
20292.70.008.2

Member Species In Iowa

Game birds species in Iowa.
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 →
Northern BobwhiteOdontophoridae-68%
Ring-necked PheasantPhasianidae-29%
Gray PartridgePhasianidae+83%
Wild TurkeyPhasianidae13×

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