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

Grasshopper Sparrow In Central Hardwoods

All regionsCentral HardwoodsGrassland birds

Grasshopper Sparrow in Central Hardwoods has collapsed: down 93% on the route-weighted index since 1968.

-93%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 →
140Routes 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 →

Grasshopper Sparrow has collapsed in Central Hardwoods: down 93% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Grasshopper Sparrow in Central Hardwoods is projected to fall about 20% by 2029 — from 0.45 in 2024 to a central estimate of 0.36 (95% range 0.00–2.1). A 5-year backtest shows a typical error of ±65.6%, with 100% of held-out values landing inside the 95% band.

-20%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 →
0.36Projected 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 →
0.00–2.195% 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 →
±65.6%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, Grasshopper Sparrow in Central Hardwoods is projected to fall about 20% by 2029 — from 0.45 in 2024 to a central estimate of 0.36 (95% range 0.00–2.1). A 5-year backtest shows a typical error of ±65.6%, 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 →
20250.590.002.3
20260.530.002.3
20270.470.002.2
20280.420.002.2
20290.360.002.1

Routes In Central Hardwoods

Routes recording Grasshopper 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 →
FarwellARKANSAS122018
NewberryINDIANA92024
CourtlandALABAMA52006
RussellARKANSAS42021
YorkILLINOIS42024
Cave In RockILLINOIS42017
RoyaltonILLINOIS42024
KarnakILLINOIS42015
HudsonKENTUCKY42016
GoshenKENTUCKY41992
GlencoeKENTUCKY42018
Lebanon JunctionKENTUCKY42013
GranitevilleMISSOURI41986
CampbellsvilleTENNESSEE41992
Ravenden SpringsARKANSAS32014
CumbackINDIANA32016
VevayINDIANA32001
ScottsburgINDIANA32014
EvansvilleINDIANA32014
Iron BridgeKENTUCKY31998
DemunbrunsKENTUCKY32005
DrakesboroKENTUCKY31993
Levee 2KENTUCKY32019
DixonKENTUCKY32022
Peace ValleyMISSOURI32023

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