Species · New Jersey · BBS 2025 Release · 1966–2024

Vesper Sparrow Population Trend in New Jersey

Vesper Sparrow in New Jersey has fallen sharply: down 67% on the route-weighted index since 1968.

-67%Since 1968
11Routes In State
24Years

Notable Vesper Sparrow Trends in New Jersey

long arc declinecomputed index

Vesper Sparrow has fallen sharply in New Jersey: down 67% on the route-weighted index since 1968.

Vesper Sparrow Population Forecast in New Jersey

If the recent trend holds, Vesper Sparrow in New Jersey is projected to fall about 89% by 2007 — from 0.05 in 2002 to a central estimate of 0.01 (95% range 0.00–0.17). A 5-year backtest shows a typical error of ±55.6%, with 100% of held-out values landing inside the 95% band.

-89%Change by 2007
0.01Projected 2007 index
0.000.1795% range
±55.6%Backtest error
19662007
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
20030.020.000.18
20040.020.000.18
20050.010.000.17
20060.010.000.17
20070.010.000.17

Vesper Sparrow Survey Routes in New Jersey

Routes recording Vesper Sparrow in New Jersey.
Sandbrook219691969
Six Points119781978
Ancora119701968
Masonville119671966
Bennett Mill119721968
New Bedford120021970
Robbinsville119691968
Bloomsbury119951969
High Point120011988
Pottersville119801980
Roosevelt119941994

Vesper Sparrow Population Trend in Other States

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