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

Brewer's Sparrow In Northern Rockies

All regionsNorthern RockiesGeneralists

Brewer's Sparrow in Northern Rockies has surged: up 140% on the route-weighted index since 1970.

+140%Since 1970
169Routes In Region
56Years

Notable Signals

long arc increasecomputed index

Brewer's Sparrow has surged in Northern Rockies: up 140% on the route-weighted index since 1970.

Forecast

If the recent trend holds, Brewer's Sparrow in Northern Rockies is projected to fall about 29% by 2029 — from 19 in 2024 to a central estimate of 13 (95% range 6.5–20). A 5-year backtest shows a typical error of ±20.6%, with 100% of held-out values landing inside the 95% band.

-29%Change by 2029
13Projected 2029 index
6.5–2095% range
±20.6%Backtest error
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 index95% low95% high
2025136.420
2026136.420
2027136.420
2028136.420
2029136.520

Routes In Northern Rockies

Routes recording Brewer's Sparrow in Northern Rockies.
Black Rock 2WYOMING1402024
Seedskadee 2WYOMING1262024
Bear CreekWYOMING1152024
RyegrassWYOMING1102024
Rawlins 2WYOMING1092024
Neponset ResUTAH1082018
Browns ParkCOLORADO982024
MeeteetseWYOMING942024
MckinnonWYOMING861986
Great DivideCOLORADO842024
BeaverheadMONTANA842024
BaggsWYOMING822024
Clover CreekOREGON802024
BairoilWYOMING802024
LayCOLORADO742024
Saleratus CrUTAH722018
MaybellCOLORADO692024
Patrick DrawWYOMING631980
RelianceWYOMING632018
LamontWYOMING622024
DiamondvilleWYOMING601982
Flamin GorgeWYOMING602024
Mtn ViewWYOMING592024
Elk Horn 2WYOMING582024
Sawtooth CtyIDAHO522014

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