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Species · Pennsylvania · BBS 2025 Release · 1966–2024

Vesper Sparrow Population Trend in Pennsylvania

All statesGrassland birds

Vesper Sparrow in Pennsylvania has collapsed: down 96% on the route-weighted index since 1968.

-96%Since 1968
104Routes In State
58Years

Notable Vesper Sparrow Trends in Pennsylvania

long arc declinecomputed index

Vesper Sparrow has collapsed in Pennsylvania: down 96% on the route-weighted index since 1968.

Vesper Sparrow Population Forecast in Pennsylvania

If the recent trend holds, Vesper Sparrow in Pennsylvania is projected to fall about 100% by 2029 — from 0.09 in 2024 to a central estimate of 0.00 (95% range 0.00–0.71). A 5-year backtest shows a typical error of ±337.5%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.00–0.7195% range
±337.5%Backtest error
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 index95% low95% high
20250.000.000.71
20260.000.000.71
20270.000.000.71
20280.000.000.71
20290.000.000.71

Vesper Sparrow Survey Routes in Pennsylvania

Routes recording Vesper Sparrow in Pennsylvania.
Needmore619911966
Ravensburg519661966
Brunnerville520091969
Pottersdale419941969
Normalville419701966
Big Flat419811967
Akeley319701967
Mifflintown320021966
Carsonville320161966
Quakertown319721971
Jeannette320221979
Jacobus319941986
Roulette219881988
Rosecrans220191969
Ralston219661966
Waller220231971
Honesdale220111974
Starlight219971970
Plesant Grov219921989
Parkwood220041967
Kittanning220231987
Virginia220011969
Geeseytown220241994
St College220241969
Peters Mt219761974

Vesper Sparrow Population Trend in Other States

arizonacaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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