BirdAnalyst
Species · BCR 16 · BBS 2025 Release · 1966–2024

Savannah Sparrow In Southern Rockies / Colorado Plateau

All regionsSouthern Rockies / Colorado PlateauGrassland birds

Savannah Sparrow in Southern Rockies / Colorado Plateau has surged: up 157% on the route-weighted index since 1970.

+157%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 →
110Routes 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 →

Savannah Sparrow has surged in Southern Rockies / Colorado Plateau: up 157% on the route-weighted index since 1970.

Forecast

If the recent trend holds, Savannah Sparrow in Southern Rockies / Colorado Plateau is projected to rise about 15% by 2029 — from 1.5 in 2024 to a central estimate of 1.7 (95% range 0.00–4.8). A 5-year backtest shows a typical error of ±27.6%, with 100% of held-out values landing inside the 95% band.

+15%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 →
1.7Projected 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 →
0.00–4.895% 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 →
±27.6%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, Savannah Sparrow in Southern Rockies / Colorado Plateau is projected to rise about 15% by 2029 — from 1.5 in 2024 to a central estimate of 1.7 (95% range 0.00–4.8). A 5-year backtest shows a typical error of ±27.6%, 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 →
20251.70.004.8
20261.70.004.8
20271.70.004.8
20281.70.004.8
20291.70.004.8

Routes In Southern Rockies / Colorado Plateau

Routes recording Savannah Sparrow in Southern Rockies / Colorado Plateau.
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 →
WaldenCOLORADO432024
YampaCOLORADO422023
CastletonCOLORADO272024
Steamboat L.COLORADO192024
DoylevilleCOLORADO172024
Weston PassCOLORADO172000
Angel FireNEW-MEXICO162002
HeeneyCOLORADO142019
Uintah NfUTAH131994
ParlinCOLORADO112023
Gribbles PrkCOLORADO112024
Hill CreekUTAH111993
KamasUTAH112024
YampaiARIZONA91970
Ragged Mtn.COLORADO72019
BufordCOLORADO62024
Fish Lake NfUTAH61999
ColonaCOLORADO52012
Piceance BasinCOLORADO52004
Stillwater Pass 2COLORADO52024
Willow CreekUTAH52001
VernalUTAH52017
BicknellUTAH52021
TarryallCOLORADO42023
UncompahgreCOLORADO41998

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