BirdAnalyst
Species · BCR 23 · BBS 2025 Release · 1966–2024

Swamp Sparrow In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionGeneralists

Swamp Sparrow in Prairie Hardwood Transition has risen sharply: up 59% on the route-weighted index since 1968.

+59%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 →
133Routes 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 →
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 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 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 →

Swamp Sparrow has risen sharply in Prairie Hardwood Transition: up 59% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Swamp Sparrow in Prairie Hardwood Transition is projected to stay roughly flat through 2029, near 2.2 (95% range 1.6–2.8). A 5-year backtest shows a typical error of ±10%, 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 →
2.2Projected 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 →
1.6–2.895% 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 →
±10%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, Swamp Sparrow in Prairie Hardwood Transition is projected to stay roughly flat through 2029, near 2.2 (95% range 1.6–2.8). A 5-year backtest shows a typical error of ±10%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20252.21.62.7
20262.21.62.7
20272.21.62.7
20282.21.62.8
20292.21.62.8

Routes In Prairie Hardwood Transition

Routes recording Swamp Sparrow in Prairie 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 →
Sherburne NrMINNESOTA272024
Brook ParkMINNESOTA172024
MinnetonkaMINNESOTA142024
Omro 2WISCONSIN142024
MatherWISCONSIN132023
EvergreenMINNESOTA122024
AshbyMINNESOTA122021
BriggsvilleWISCONSIN112024
Chippewa Lk.MICHIGAN102024
CumberlandWISCONSIN92024
KnappMINNESOTA82024
EdwardsMINNESOTA82006
New LondonMINNESOTA72024
Fall RiverWISCONSIN72024
NashvilleMICHIGAN62024
GalesburgMICHIGAN62024
HowardsvilleMICHIGAN62024
PettysvilleMICHIGAN61979
GlenwoodMINNESOTA62019
EdenWISCONSIN62024
LapeerMICHIGAN52024
GilmantonWISCONSIN51988
UnityWISCONSIN52024
ClintonvilleWISCONSIN52024
PardeevilleWISCONSIN52024

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