BirdAnalyst
Species · BCR 17 · BBS 2025 Release · 1966–2024

Swainson's Thrush In Badlands and Prairies

All regionsBadlands and PrairiesForest birds

Swainson's Thrush in Badlands and Prairies has surged: up 986% on the route-weighted index since 1972.

+986%Since 1972TrendPercent 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 →
25Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
53YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed 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 →

Swainson's Thrush has surged in Badlands and Prairies: up 986% on the route-weighted index since 1972.

Swainson's Thrush In Badlands and Prairies Population Forecast

If the recent trend holds, Swainson's Thrush in Badlands and Prairies is projected to rise about 51% by 2029 — from 0.70 in 2024 to a central estimate of 1.1 (95% range 0.16–1.9). A 5-year backtest shows a typical error of ±112.4%, with 100% of held-out values landing inside the 95% band.

+51%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 →
1.1Projected 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 →
0.16–1.995% 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 →
±112.4%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 Badlands and Prairies is projected to rise about 51% by 2029 — from 0.70 in 2024 to a central estimate of 1.1 (95% range 0.16–1.9). A 5-year backtest shows a typical error of ±112.4%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.990.101.9
20261.00.111.9
20271.00.131.9
20281.00.141.9
20291.10.161.9

Routes In Badlands and Prairies

Routes recording Swainson's Thrush in Badlands and Prairies.
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 →
Long DrawSOUTH-DAKOTA362024
Black FoxSOUTH-DAKOTA312017
NorbeckSOUTH-DAKOTA292002
EnglewoodSOUTH-DAKOTA172021
RochfordSOUTH-DAKOTA142018
Maynard CouleeMONTANA72024
Silver CitySOUTH-DAKOTA62012
CusterSOUTH-DAKOTA52024
Lightning CrSOUTH-DAKOTA22000
HighwoodMONTANA12011
Two DotMONTANA11987
Reed PointMONTANA12014
Roubaix LkSOUTH-DAKOTA11990
Hill CitySOUTH-DAKOTA12013
Elk MountainSOUTH-DAKOTA12004
HazelrodtSOUTH-DAKOTA12022
Wind Cave NpSOUTH-DAKOTA12013
WyarnoWYOMING11978
SundanceWYOMING12023
DaytonWYOMING12005
MoskeeWYOMING11991
ShawneeWYOMING12004
Seely 2WYOMING12006
Moskee 2WYOMING12019
Moskee 3WYOMING12024

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