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

Tree Swallow In Southern Rockies / Colorado Plateau

All regionsSouthern Rockies / Colorado PlateauAerial insectivores

Tree Swallow in Southern Rockies / Colorado Plateau has edged down: down 23% on the route-weighted index since 1970.

-23%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 →
155Routes 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 →
57YearsYears 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 Tree Swallow in Southern Rockies / Colorado Plateau. See the full index history below.

Tree Swallow In Southern Rockies / Colorado Plateau Population Forecast

If the recent trend holds, Tree Swallow in Southern Rockies / Colorado Plateau is projected to rise about 43% by 2030 — from 2.2 in 2025 to a central estimate of 3.1 (95% range 0.26–6.0). A 5-year backtest shows a typical error of ±64.1%, with 100% of held-out values landing inside the 95% band.

+43%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 →
3.1Projected 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 →
0.26–6.095% 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 →
±64.1%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, Tree Swallow in Southern Rockies / Colorado Plateau is projected to rise about 43% by 2030 — from 2.2 in 2025 to a central estimate of 3.1 (95% range 0.26–6.0). A 5-year backtest shows a typical error of ±64.1%, 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 →
20263.20.286.0
20273.20.286.0
20283.10.276.0
20293.10.266.0
20303.10.266.0

Routes In Southern Rockies / Colorado Plateau

Routes recording Tree Swallow 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 →
CebollaNEW-MEXICO242018
YampaCOLORADO232023
Weston PassCOLORADO212000
ParlinCOLORADO202025
MonticelloUTAH192024
HannaUTAH172024
Pagosa SpgsCOLORADO161978
Lost LakeCOLORADO162025
Rio Grnds RsCOLORADO162024
De BequeCOLORADO152025
BeckUTAH151987
Deadman Rd.COLORADO142025
Trail Ridge RoadCOLORADO142014
Skyline DrivUTAH142025
M Warner ResUTAH142025
La SalUTAH141998
Steamboat L.COLORADO122025
HeeneyCOLORADO122019
Fox ParkWYOMING122025
Dry ParkARIZONA112000
BufordCOLORADO112025
Lake CityCOLORADO112000
Gold HillCOLORADO112012
CortezCOLORADO102008
ShivwitzUTAH102025

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