BirdAnalyst
Species · BCR 16 · BBS 2026 Release · 1966–2025

Lark Bunting In Southern Rockies / Colorado Plateau

All regionsSouthern Rockies / Colorado PlateauGrassland birds

Lark Bunting in Southern Rockies / Colorado Plateau has collapsed: down 97% on the route-weighted index since 1970.

-97%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 →
46Routes 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 declinecomputed 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 →

Lark Bunting has collapsed in Southern Rockies / Colorado Plateau: down 97% on the route-weighted index since 1970.

Lark Bunting In Southern Rockies / Colorado Plateau Population Forecast

If the recent trend holds, Lark Bunting in Southern Rockies / Colorado Plateau is projected to fall about 100% by 2030 — from 0.41 in 2025 to a central estimate of 0.00 (95% range 0.00–3.7). A 5-year backtest shows a typical error of ±3302.4%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2030TrendPercent 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 →
0.00Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–3.795% 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 →
±3302.4%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, Lark Bunting in Southern Rockies / Colorado Plateau is projected to fall about 100% by 2030 — from 0.41 in 2025 to a central estimate of 0.00 (95% range 0.00–3.7). A 5-year backtest shows a typical error of ±3302.4%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.000.003.7
20270.000.003.7
20280.000.003.7
20290.000.003.7
20300.000.003.7

Routes In Southern Rockies / Colorado Plateau

Routes recording Lark Bunting 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 →
San LuisCOLORADO442025
AlamosaCOLORADO102015
MesitaCOLORADO92025
WestcliffeCOLORADO82012
Wet Mtns.COLORADO71994
Sybille CynWYOMING72024
Douglas PassCOLORADO61982
Mt TrumbullARIZONA51978
AntonitoCOLORADO52004
Red Spur Mtn.UTAH52004
MoscaCOLORADO42025
PasturaNEW-MEXICO42015
Gallo ArroyoNEW-MEXICO42007
Cane Spr DesUTAH41992
BrookhurstWYOMING42022
WarbonnetWYOMING42017
BufordCOLORADO31992
Blackhead PkCOLORADO31994
NotomUTAH32023
WestwaterUTAH32011
Gribbles PrkCOLORADO21997
TorreonNEW-MEXICO21975
AztecNEW-MEXICO21988
M Warner ResUTAH22022
BufordWYOMING22025

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.