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

Purple Martin In Southern Rockies / Colorado Plateau

All regionsSouthern Rockies / Colorado PlateauAerial insectivores

Purple Martin in Southern Rockies / Colorado Plateau has declined: down 45% on the route-weighted index since 1970.

-45%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 →
51Routes 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 →
55YearsYears 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 →

No notable trend signals for Purple Martin in Southern Rockies / Colorado Plateau. See the full index history below.

Forecast

If the recent trend holds, Purple Martin in Southern Rockies / Colorado Plateau is projected to rise about 52% by 2029 — from 0.21 in 2024 to a central estimate of 0.32 (95% range 0.04–0.59). A 5-year backtest shows a typical error of ±83.4%, with 100% of held-out values landing inside the 95% band.

+52%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 →
0.32Projected 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 →
0.04–0.5995% 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 →
±83.4%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, Purple Martin in Southern Rockies / Colorado Plateau is projected to rise about 52% by 2029 — from 0.21 in 2024 to a central estimate of 0.32 (95% range 0.04–0.59). A 5-year backtest shows a typical error of ±83.4%, 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 →
20250.310.030.58
20260.310.040.58
20270.310.040.58
20280.320.040.59
20290.320.040.59

Routes In Southern Rockies / Colorado Plateau

Routes recording Purple Martin 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 →
Ragged Mtn.COLORADO152019
SawmillARIZONA112014
UncompahgreCOLORADO102024
Colona 2COLORADO62021
Haycamp MesaCOLORADO52010
DoloresCOLORADO31968
FlattopsCOLORADO32018
Groundhog RsCOLORADO32024
Fence LakeNEW-MEXICO32024
AnethUTAH32024
Lost Cr. ResUTAH32016
HuntARIZONA21976
YampaCOLORADO22018
Douglas PassCOLORADO22022
ThomasvilleCOLORADO22017
CokedaleCOLORADO22024
Yellowjacket PassCOLORADO21998
Horse MtnNEW-MEXICO22011
Claunch 2NEW-MEXICO22024
DulceNEW-MEXICO22024
Mt. Taylor 2NEW-MEXICO22022
BeckUTAH21977
Fish Lake NfUTAH22024
SoapstoneUTAH22007
ZeniffARIZONA11972

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