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

Grasshopper Sparrow Population Trend in New Jersey

Grasshopper Sparrow in New Jersey has fallen sharply: down 62% on the route-weighted index since 1969.

-62%Since 1969
29Routes In State
53Years

Notable Grasshopper Sparrow Trends in New Jersey

long arc declinecomputed index

Grasshopper Sparrow has fallen sharply in New Jersey: down 62% on the route-weighted index since 1969.

Grasshopper Sparrow Population Forecast in New Jersey

If the recent trend holds, Grasshopper Sparrow in New Jersey is projected to fall about 17% by 2029 — from 0.19 in 2024 to a central estimate of 0.16 (95% range 0.00–0.45). A 5-year backtest shows a typical error of ±52.5%, with 100% of held-out values landing inside the 95% band.

-17%Change by 2029
0.16Projected 2029 index
0.000.4595% range
±52.5%Backtest error
19672029
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
20250.170.000.46
20260.160.000.46
20270.160.000.46
20280.160.000.45
20290.160.000.45

Grasshopper Sparrow Survey Routes in New Jersey

Routes recording Grasshopper Sparrow in New Jersey.
Croton520071970
Woodbury Hgt320241967
Bloomsbury319911969
Roosevelt320071986
Deepwater219771971
Hope219771977
Pottersville220221977
Greenwich120221978
Six Points120191978
Toms River120051996
Albion119771968
Bennett Mill119761976
Sandbrook120231969
Holmansville119961981
Clarksville119761973
New Bedford119731970
Midvale119751975
Kemah Lake120051969
High Point119881988
Keyport119951990
Cranbury119971997
Friendship120182016
Pomona119901990
Mt Misery119891977
Pedricktown 2120172017

Grasshopper Sparrow Population Trend in Other States

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