BirdAnalyst
Species · BCR 24 · BBS 2025 Release · 1966–2024

Field Sparrow In Central Hardwoods

All regionsCentral HardwoodsGeneralists

Field Sparrow in Central Hardwoods has fallen sharply: down 69% on the route-weighted index since 1968.

-69%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 →
166Routes 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 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 Central Hardwoods: down 69% on the route-weighted index since 1968.

Field Sparrow In Central Hardwoods Population Forecast

If the recent trend holds, Field Sparrow in Central Hardwoods is projected to fall about 29% by 2029 — from 11 in 2024 to a central estimate of 8.0 (95% range 0.00–16). A 5-year backtest shows a typical error of ±25.6%, with 100% of held-out values landing inside the 95% band.

-29%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 →
8.0Projected 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 →
0.00–1695% 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 →
±25.6%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 Central Hardwoods is projected to fall about 29% by 2029 — from 11 in 2024 to a central estimate of 8.0 (95% range 0.00–16). A 5-year backtest shows a typical error of ±25.6%, 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 →
20259.21.117
20268.90.8417
20278.60.5317
20288.30.2316
20298.00.0016

Routes In Central Hardwoods

Routes recording Field Sparrow in Central Hardwoods.
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 →
RoyaltonILLINOIS452024
Bays ForkKENTUCKY422019
DrakesboroKENTUCKY381993
Beaverdam LkILLINOIS312023
Peace ValleyMISSOURI312024
Osage BeachMISSOURI312024
BelknapILLINOIS302024
Cole CampMISSOURI291990
RichlandMISSOURI282021
SwaimALABAMA252024
BremenILLINOIS252024
GraydonMISSOURI252024
West PlainsMISSOURI252024
RomeOHIO252024
FarwellARKANSAS232018
Iron BridgeKENTUCKY231998
JohnsonvilleKENTUCKY222021
Buena VistaKENTUCKY222017
BlandMISSOURI222024
LeveeKENTUCKY211982
EugeneMISSOURI212024
PetersburgTENNESSEE212019
SwedenMISSOURI202024
PeytonsvilleTENNESSEE202024
MerrimacKENTUCKY192024

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