BirdAnalyst
Species · Minnesota · BBS 2026 Release · 1966–2025

Tree Swallow Population Trend in Minnesota

All statesAerial insectivores

Tree Swallow in Minnesota has risen sharply: up 64% on the route-weighted index since 1969.

+64%Since 1969TrendPercent 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 →
91Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Tree Swallow Trends in MinnesotaNotable 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 increasecomputed 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 →

Tree Swallow has risen sharply in Minnesota: up 64% on the route-weighted index since 1969.

Tree Swallow Population Forecast in Minnesota

If the recent trend holds, Tree Swallow in Minnesota is projected to rise about 114% by 2030 — from 3.9 in 2025 to a central estimate of 8.3 (95% range 3.5–13). A 5-year backtest shows a typical error of ±105.6%, with 20% of held-out values landing inside the 95% band.

+114%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 →
8.3Projected 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 →
3.5–1395% 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 →
±105.6%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 Minnesota is projected to rise about 114% by 2030 — from 3.9 in 2025 to a central estimate of 8.3 (95% range 3.5–13). A 5-year backtest shows a typical error of ±105.6%, with 20% of held-out values landing inside the 95% band.19672030
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 →
20268.13.413
20278.23.413
20288.23.413
20298.23.513
20308.33.513

Tree Swallow Survey Routes in Minnesota

Routes recording Tree Swallow in Minnesota.
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 →
Edwards4520241973
Bagley2720061995
Knapp2320251968
Sherburne Nr2020251990
New London1920241994
Glenwood1520191993
Brainerd1520241993
St Stephen1420251968
Ashby1420211997
Whitewater 21320192011
Minnetonka1220251969
Osseo1020251967
Wigwam Bay1020231967
Whitewater1020001994
Chokio920251970
Le Center920251993
Tyler920251993
Brook Park920251998
Island Lake819951967
Appleton720251978
Evergreen720251967
Tenney720161978
Beltrami720251967
Big Stone720121995
Millville620251967

Tree Swallow Population Trend in Other States

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

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