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

Tree Swallow In Northern Rockies

All regionsNorthern RockiesAerial insectivores

Tree Swallow in Northern Rockies has increased: up 32% on the route-weighted index since 1970.

+32%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 →
183Routes 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 →

No notable trend signals for Tree Swallow in Northern Rockies. See the full index history below.

Tree Swallow In Northern Rockies Population Forecast

If the recent trend holds, Tree Swallow in Northern Rockies is projected to stay roughly flat through 2029, near 5.8 (95% range 3.3–8.3). A 5-year backtest shows a typical error of ±9.9%, with 100% of held-out values landing inside the 95% band.

+9%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 →
5.8Projected 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 →
3.3–8.395% 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 →
±9.9%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 Northern Rockies is projected to stay roughly flat through 2029, near 5.8 (95% range 3.3–8.3). A 5-year backtest shows a typical error of ±9.9%, 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 →
20255.73.38.2
20265.83.38.2
20275.83.38.2
20285.83.38.3
20295.83.38.3

Routes In Northern Rockies

Routes recording Tree Swallow in Northern Rockies.
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 →
Red RockMONTANA1152024
CascadeIDAHO711984
Green RiverWYOMING671984
Pablo Res.MONTANA392024
Hebgen LakeMONTANA372024
CodyWYOMING322024
ChestnutMONTANA272024
CabartonIDAHO262023
Clyde ParkMONTANA242024
BeaverheadMONTANA212024
MeeteetseWYOMING202024
KalispellMONTANA192024
St. Mary 2MONTANA192024
SeedskadeeWYOMING192023
BoulderWYOMING182024
Seedskadee 2WYOMING182024
NezperceIDAHO162007
Hayden ValWYOMING161986
CentervilleIDAHO152019
WoodmanMONTANA152024
EllistonMONTANA152024
Logan PassMONTANA142024
SaveryWYOMING141995
MammothWYOMING142024
NinemileMONTANA132024

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