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

Grassland Birds In Wyoming

All statesWyoming

13 species in this guild. As a group they are -54%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 →

Grassland birds as a group have fallen sharply in Wyoming, down 54% since 1970.

Grassland Birds In Wyoming Population Forecast

If the recent trend holds, Grassland birds in Wyoming is projected to fall about 46% by 2029 — from 15 in 2024 to a central estimate of 8.1 (95% range 0.00–17). A 5-year backtest shows a typical error of ±34.8%, with 100% of held-out values landing inside the 95% band.

-46%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 →
8.1Projected 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 →
0.00–1795% 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 →
±34.8%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, Grassland birds in Wyoming is projected to fall about 46% by 2029 — from 15 in 2024 to a central estimate of 8.1 (95% range 0.00–17). A 5-year backtest shows a typical error of ±34.8%, 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 →
20259.50.3519
20269.20.0018
20278.80.0018
20288.40.0018
20298.10.0017

Member Species In Wyoming

Grassland birds species in Wyoming.
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 →
Lark BuntingPasserellidae-69%
Ring-necked PheasantPhasianidae-67%
Northern BobwhiteOdontophoridae-58%
Baird's SparrowPasserellidae-40%
Horned LarkAlaudidae-39%
Western MeadowlarkIcteridae-18%
Lark SparrowPasserellidae-3%
Vesper SparrowPasserellidae+34%
Grasshopper SparrowPasserellidae+63%
DickcisselCardinalidae+73%
BobolinkIcteridae+170%
Upland SandpiperScolopacidae+331%
Savannah SparrowPasserellidae+509%

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