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Species · BCR 12 · BBS 2026 Release · 1966–2025

Bank Swallow In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionAerial insectivores

Bank Swallow in Boreal Hardwood Transition has collapsed: down 89% on the route-weighted index since 1968.

-89%Since 1968TrendPercent 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 →
93Routes 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 →
59YearsYears 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 →

Bank Swallow has collapsed in Boreal Hardwood Transition: down 89% on the route-weighted index since 1968.

Bank Swallow In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Bank Swallow in Boreal Hardwood Transition is projected to fall about 84% by 2030 — from 0.34 in 2025 to a central estimate of 0.06 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±118.5%, with 100% of held-out values landing inside the 95% band.

-84%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 →
0.06Projected 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 →
0.00–1.795% 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 →
±118.5%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, Bank Swallow in Boreal Hardwood Transition is projected to fall about 84% by 2030 — from 0.34 in 2025 to a central estimate of 0.06 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±118.5%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.220.001.9
20270.180.001.8
20280.140.001.8
20290.100.001.8
20300.060.001.7

Routes In Boreal Hardwood Transition

Routes recording Bank Swallow in Boreal Hardwood Transition.
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 →
BerglandMICHIGAN411993
WilsonMICHIGAN402007
BenaMINNESOTA201967
IrmaWISCONSIN122000
HollisterWISCONSIN122012
CathroMICHIGAN102007
Pine RiverMINNESOTA102025
LudeMINNESOTA102016
BagleyMINNESOTA101995
BootjackMICHIGAN82009
NebishMINNESOTA81993
CavourWISCONSIN82009
BemidjiMINNESOTA71980
MahtowaMINNESOTA71993
OntonagonMICHIGAN61971
MareniscoMICHIGAN62003
Walloon Lake 2MICHIGAN62024
MayfieldMICHIGAN62025
CouderayWISCONSIN62017
ExelandWISCONSIN62010
IshpemingMICHIGAN51991
CreightonMICHIGAN52019
SkeelsMICHIGAN52008
Red OakMICHIGAN51990
Pleasant Valley 2MICHIGAN52025

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