BirdAnalyst
Species · BCR 23 · BBS 2026 Release · 1966–2025

Swamp Sparrow In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionWetland birds

Swamp Sparrow in Prairie Hardwood Transition has risen sharply: up 68% on the route-weighted index since 1968.

+68%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 →
134Routes 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 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 68% on the route-weighted index since 1968.

Swamp Sparrow In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Swamp Sparrow in Prairie Hardwood Transition is projected to stay roughly flat through 2030, near 2.2 (95% range 1.7–2.8). A 5-year backtest shows a typical error of ±11.3%, with 100% of held-out values landing inside the 95% band.

-4%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 →
2.2Projected 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 →
1.7–2.895% 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 →
±11.3%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 2030, near 2.2 (95% range 1.7–2.8). A 5-year backtest shows a typical error of ±11.3%, 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 →
20262.21.62.7
20272.21.62.8
20282.21.62.8
20292.21.62.8
20302.21.72.8

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 →
Omro 2WISCONSIN162025
MatherWISCONSIN132023
MinnetonkaMINNESOTA122025
AshbyMINNESOTA122021
Chippewa Lk.MICHIGAN102025
Sherburne NrMINNESOTA102025
Brook ParkMINNESOTA92025
LoraineWISCONSIN92025
NashvilleMICHIGAN82025
EdwardsMINNESOTA82006
BriggsvilleWISCONSIN82025
KnappMINNESOTA72025
New LondonMINNESOTA72024
PardeevilleWISCONSIN72025
KielWISCONSIN72025
GalesburgMICHIGAN62025
HowardsvilleMICHIGAN62025
PettysvilleMICHIGAN61979
LapeerMICHIGAN62025
GlenwoodMINNESOTA62019
CumberlandWISCONSIN62025
UnityWISCONSIN62025
HebronWISCONSIN62025
EvergreenMINNESOTA52025
GilmantonWISCONSIN51988

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