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

Field Sparrow In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionForest birds

Field Sparrow in Prairie Hardwood Transition has fallen sharply: down 64% on the route-weighted index since 1968.

-64%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 →
157Routes 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 →

Field Sparrow has fallen sharply in Prairie Hardwood Transition: down 64% on the route-weighted index since 1968.

Field Sparrow In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Field Sparrow in Prairie Hardwood Transition is projected to fall about 36% by 2030 — from 3.9 in 2025 to a central estimate of 2.5 (95% range 0.55–4.4). A 5-year backtest shows a typical error of ±30.7%, with 100% of held-out values landing inside the 95% band.

-36%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 →
2.5Projected 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 →
0.55–4.495% 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 →
±30.7%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, Field Sparrow in Prairie Hardwood Transition is projected to fall about 36% by 2030 — from 3.9 in 2025 to a central estimate of 2.5 (95% range 0.55–4.4). A 5-year backtest shows a typical error of ±30.7%, 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 →
20263.01.04.9
20272.80.924.7
20282.70.804.6
20292.60.674.5
20302.50.554.4

Routes In Prairie Hardwood Transition

Routes recording Field 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 →
EllisINDIANA382024
Drayton PlnsMICHIGAN351987
Sherburne NrMINNESOTA262025
GuilfordILLINOIS252023
GalesburgMICHIGAN172025
KnoxINDIANA162025
ScottvilleMICHIGAN132025
HowardsvilleMICHIGAN132025
Caledonia 2MINNESOTA132025
WhitewaterMINNESOTA132000
HatfieldWISCONSIN131998
N FreedomWISCONSIN132025
Lake GalenaILLINOIS122021
PackertownINDIANA122004
RemusMICHIGAN122025
AlmenaMICHIGAN122015
WiotaWISCONSIN122025
NashvilleMICHIGAN112025
Barry S.G.A.MICHIGAN112012
MillvilleMINNESOTA112025
CaledoniaMINNESOTA112012
Money CreekMINNESOTA102023
Rolling GrndWISCONSIN102025
New LisbonWISCONSIN102025
BriggsvilleWISCONSIN102025

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