BirdAnalyst
Species · BCR 29 · BBS 2025 Release · 1966–2024

Grasshopper Sparrow In Piedmont

All regionsPiedmontGrassland birds

Grasshopper Sparrow in Piedmont has collapsed: down 77% on the route-weighted index since 1968.

-77%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 →
144Routes 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 Piedmont: down 77% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Grasshopper Sparrow in Piedmont is projected to fall about 59% by 2029 — from 1.6 in 2024 to a central estimate of 0.67 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±45%, with 100% of held-out values landing inside the 95% band.

-59%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 →
0.67Projected 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 →
0.00–2.495% 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 →
±45%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 Piedmont is projected to fall about 59% by 2029 — from 1.6 in 2024 to a central estimate of 0.67 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±45%, 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 →
20250.940.002.7
20260.870.002.6
20270.800.002.5
20280.730.002.5
20290.670.002.4

Routes In Piedmont

Routes recording Grasshopper Sparrow in Piedmont.
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 →
EmmitsburgMARYLAND262024
CherryvilleNORTH-CAROLINA161968
PendletonSOUTH-CAROLINA151976
Mooresville 2NORTH-CAROLINA122024
WylliesburgVIRGINIA102019
MadonnaMARYLAND92022
OstwaltNORTH-CAROLINA92024
CampobelloSOUTH-CAROLINA92024
FlayNORTH-CAROLINA82024
TaylorstownVIRGINIA82010
MoranVIRGINIA82024
OwingsSOUTH-CAROLINA62004
Brandy StationVIRGINIA62024
LincolntonGEORGIA51995
RutledgeGEORGIA52024
Stoney Point 2GEORGIA52019
IjamsvilleMARYLAND52024
CrotonNEW-JERSEY52007
LabottPENNSYLVANIA51983
ShrewsburyPENNSYLVANIA52023
PartlowVIRGINIA52007
MetasvilleGEORGIA42000
EkloMARYLAND42018
WheatonMARYLAND41995
MadisonNORTH-CAROLINA41985

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