BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Sage Thrasher In Northern Rockies

All regionsNorthern RockiesGeneralists

Sage Thrasher in Northern Rockies has surged: up 114% on the route-weighted index since 1970.

+114%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 →
119Routes 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 →
56YearsYears 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 →

Sage Thrasher has surged in Northern Rockies: up 114% on the route-weighted index since 1970.

Sage Thrasher In Northern Rockies Population Forecast

If the recent trend holds, Sage Thrasher in Northern Rockies is projected to fall about 40% by 2029 — from 9.5 in 2024 to a central estimate of 5.7 (95% range 0.00–14). A 5-year backtest shows a typical error of ±18.7%, with 100% of held-out values landing inside the 95% band.

-40%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 →
5.7Projected 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 →
0.00–1495% 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 →
±18.7%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, Sage Thrasher in Northern Rockies is projected to fall about 40% by 2029 — from 9.5 in 2024 to a central estimate of 5.7 (95% range 0.00–14). A 5-year backtest shows a typical error of ±18.7%, 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 →
20256.10.0015
20266.00.0015
20275.90.0015
20285.80.0015
20295.70.0014

Routes In Northern Rockies

Routes recording Sage Thrasher in Northern Rockies.
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 →
Patrick DrawWYOMING921980
Patrick Draw 2WYOMING851983
MckinnonWYOMING811986
Black Rock 2WYOMING782024
Bear CreekWYOMING752024
BairoilWYOMING702024
RyegrassWYOMING622024
DanielWYOMING601988
DiamondvilleWYOMING581982
Carter 2WYOMING582024
Neponset ResUTAH552018
BaggsWYOMING552024
Seedskadee 2WYOMING552024
RelianceWYOMING512018
Browns ParkCOLORADO462024
Patrick Draw 6WYOMING452024
Saleratus CrUTAH412018
ShirleyWYOMING402024
Rawlins 2WYOMING402024
Mtn ViewWYOMING392024
MaybellCOLORADO372024
Great DivideCOLORADO372024
ErvayWYOMING332024
LamontWYOMING322024
Elk Horn 2WYOMING322024

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