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Species · Wyoming · BBS 2025 Release · 1966–2024

Swainson's Thrush Population Trend in Wyoming

All statesForest birds

Swainson's Thrush in Wyoming has edged down: down 14% on the route-weighted index since 1970.

-14%Since 1970TrendPercent 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 →
40Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Swainson's Thrush Trends in WyomingNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Swainson's Thrush in Wyoming. See the full index history below.

Swainson's Thrush Population Forecast in Wyoming

If the recent trend holds, Swainson's Thrush in Wyoming is projected to stay roughly flat through 2029, near 0.86 (95% range 0.10–1.6). A 5-year backtest shows a typical error of ±55.5%, with 40% of held-out values landing inside the 95% band.

-4%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 →
0.86Projected 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 →
0.10–1.695% 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 →
±55.5%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, Swainson's Thrush in Wyoming is projected to stay roughly flat through 2029, near 0.86 (95% range 0.10–1.6). A 5-year backtest shows a typical error of ±55.5%, with 40% 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 →
20250.830.061.6
20260.840.071.6
20270.850.081.6
20280.850.091.6
20290.860.101.6

Swainson's Thrush Survey Routes in Wyoming

Routes recording Swainson's Thrush in Wyoming.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Colter Bay 23620242019
Moran1620162002
Ne Entrance1520211982
Mammoth1220241982
Buckskin Mtn1220211981
Wilson1120241979
Colter Bay919991968
West Thumb819821982
Hunter Peak720241982
Savery519891989
Warbonnet420241990
Savery 2420242008
Ryan Park320232012
Dubois220101982
Prior Flats220051991
Riverside219991969
Bald Mtn220241992
Soda Lake220241980
Pathfinder219831983
Cody119991999
Hayden Val119861985
Wyarno119781978
Yellowstone120221988
Sundance120231975
Brookhurst120031969

Swainson's Thrush Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutidahoillinoismainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinaoregonpennsylvaniasouth-dakotautahvermontvirginiawashingtonwest-virginiawisconsin

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