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

Bobolink In Piedmont

All regionsPiedmontGrassland birds

Bobolink in Piedmont has held roughly steady: down 8% on the route-weighted index since 1973.

-8%Since 1973TrendPercent 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 →
16Routes 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 →
52YearsYears 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 Bobolink in Piedmont. See the full index history below.

Bobolink In Piedmont Population Forecast

If the recent trend holds, Bobolink in Piedmont is projected to stay roughly flat through 2029, near 0.08 (95% range 0.00–0.30). A 5-year backtest shows a typical error of ±140.2%, with 100% of held-out values landing inside the 95% band.

+0%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 →
0.08Projected 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 →
0.00–0.3095% 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 →
±140.2%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, Bobolink in Piedmont is projected to stay roughly flat through 2029, near 0.08 (95% range 0.00–0.30). A 5-year backtest shows a typical error of ±140.2%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.090.000.31
20260.080.000.31
20270.080.000.31
20280.080.000.31
20290.080.000.30

Routes In Piedmont

Routes recording Bobolink 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 →
West GrovePENNSYLVANIA81992
EmmitsburgMARYLAND72024
Brick TavernPENNSYLVANIA61991
GilletteNEW-JERSEY42015
IjamsvilleMARYLAND32002
TaylorstownVIRGINIA32007
BendersvillePENNSYLVANIA22017
ShrewsburyPENNSYLVANIA21996
WarfieldsbrgMARYLAND12016
SandbrookNEW-JERSEY12023
CrotonNEW-JERSEY12007
PottersvilleNEW-JERSEY12023
CollegevillePENNSYLVANIA12016
Doe RunPENNSYLVANIA12006
Mt Gretna 2PENNSYLVANIA12014
ChathamPENNSYLVANIA12021

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