BirdAnalyst
Species · Idaho · BBS 2025 Release · 1966–2024

Tree Swallow Population Trend in Idaho

All statesAerial insectivores

Tree Swallow in Idaho has risen sharply: up 68% on the route-weighted index since 1970.

+68%Since 1970
53Routes In State
56Years

Notable Tree Swallow Trends in Idaho

long arc increasecomputed index

Tree Swallow has risen sharply in Idaho: up 68% on the route-weighted index since 1970.

Tree Swallow Population Forecast in Idaho

If the recent trend holds, Tree Swallow in Idaho is projected to rise about 110% by 2029 — from 1.3 in 2024 to a central estimate of 2.8 (95% range 0.00–10). A 5-year backtest shows a typical error of ±38.6%, with 100% of held-out values landing inside the 95% band.

+110%Change by 2029
2.8Projected 2029 index
0.00–1095% range
±38.6%Backtest error
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 index95% low95% high
20252.90.0011
20262.90.0010
20272.90.0010
20282.80.0010
20292.80.0010

Tree Swallow Survey Routes in Idaho

Routes recording Tree Swallow in Idaho.
Henry9319831973
Cascade7119841968
Cabarton2620231985
Nezperce1620071968
Centerville1520191973
Daniels Res1520071988
Naples1220231972
Magic Mtn1220241987
Sawtooth Cty820141988
Challis620241977
Sawtooth City 2620232015
Bates620231988
Dougal Res520211989
Nezperce Nf519921992
Cape Horn420241988
Baldy Mountain420162013
Golden320161987
Alturas319861985
Almo320231991
Preston320171988
Blackft Res220181984
Mivoden220221977
Avery220162006
Lolo Pass220191992
Baker220241974

Tree Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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