BirdAnalyst
Species · BCR 22 · BBS 2026 Release · 1966–2025

Swamp Sparrow In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieWetland birds

Swamp Sparrow in Eastern Tallgrass Prairie has held roughly steady: down 9% on the route-weighted index since 1968.

-9%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 →
47Routes 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 →

No notable trend signals for Swamp Sparrow in Eastern Tallgrass Prairie. See the full index history below.

Swamp Sparrow In Eastern Tallgrass Prairie Population Forecast

If the recent trend holds, Swamp Sparrow in Eastern Tallgrass Prairie is projected to fall about 32% by 2030 — from 0.06 in 2025 to a central estimate of 0.04 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±46.2%, with 100% of held-out values landing inside the 95% band.

-32%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 →
0.04Projected 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 →
0.00–0.0995% 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 →
±46.2%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 Eastern Tallgrass Prairie is projected to fall about 32% by 2030 — from 0.06 in 2025 to a central estimate of 0.04 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±46.2%, 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 →
20260.040.000.09
20270.040.000.09
20280.040.000.09
20290.040.000.09
20300.040.000.09

Routes In Eastern Tallgrass Prairie

Routes recording Swamp Sparrow in Eastern Tallgrass Prairie.
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 →
MilfordILLINOIS61996
Ash CreekMINNESOTA42019
GaryINDIANA21987
HebronINDIANA21985
Portage 2INDIANA22025
BloomvilleOHIO22025
RaymondWISCONSIN22025
Mill CreekILLINOIS12000
HolcombILLINOIS11998
BarringtonILLINOIS11997
ItascaILLINOIS12012
AtkinsonILLINOIS12006
SheffieldILLINOIS11974
ComptonILLINOIS12025
WayneILLINOIS12025
SherburnvillILLINOIS11992
New LenoxILLINOIS11999
ChandlervillILLINOIS11974
Mt VernonILLINOIS12005
CaledoniaILLINOIS11996
Troy GroveILLINOIS12015
AldenILLINOIS12023
Lake SummersetILLINOIS12025
UnionILLINOIS12012
TiptonINDIANA11979

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