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

Barn Swallow In Northern Rockies

All regionsNorthern RockiesAerial insectivores

Barn Swallow in Northern Rockies has fallen sharply: down 51% on the route-weighted index since 1970.

-51%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 →

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 →

Barn Swallow has fallen sharply in Northern Rockies: down 51% on the route-weighted index since 1970.

Barn Swallow In Northern Rockies Population Forecast

If the recent trend holds, Barn Swallow in Northern Rockies is projected to fall about 67% by 2029 — from 2.3 in 2024 to a central estimate of 0.76 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±42%, with 100% of held-out values landing inside the 95% band.

-67%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 →
0.76Projected 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 →
0.00–3.595% 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 →
±42%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, Barn Swallow in Northern Rockies is projected to fall about 67% by 2029 — from 2.3 in 2024 to a central estimate of 0.76 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±42%, 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 →
20251.20.003.9
20261.10.003.8
20270.980.003.7
20280.870.003.6
20290.760.003.5

Routes In Northern Rockies

Routes recording Barn 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 →
BasinWYOMING502024
Browns ParkCOLORADO362007
Rock RiverWYOMING352022
CascadeIDAHO291984
MidvaleWYOMING292024
OttoWYOMING282024
RandolphUTAH182024
SpartaOREGON172001
Gas Hills 2WYOMING172024
MadrasOREGON122024
EtheteWYOMING122024
ChestnutMONTANA102018
Elk HornWYOMING102018
Bear CreekWYOMING102015
Pablo Res.MONTANA92024
Wolf CreekMONTANA92022
GeboWYOMING92024
Twin BridgesMONTANA81976
Wise RiverMONTANA82022
St. Mary 2MONTANA82023
Mount VernonOREGON82024
FrannieWYOMING82024
MeeteetseWYOMING82024
MaybellCOLORADO72024
NaplesIDAHO72024

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