BirdAnalyst
Species · BCR 34 · BBS 2025 Release · 1966–2024

Vesper Sparrow In Sierra Madre Occidental

All regionsSierra Madre OccidentalGrassland birds

Vesper Sparrow in Sierra Madre Occidental has declined: down 45% on the route-weighted index since 1970.

-45%Since 1970
11Routes In Region
44Years

Notable Signals

No notable trend signals for Vesper Sparrow in Sierra Madre Occidental. See the full index history below.

Forecast

If the recent trend holds, Vesper Sparrow in Sierra Madre Occidental is projected to rise about 52% by 2029 — from 0.83 in 2024 to a central estimate of 1.3 (95% range 0.00–3.3). A 5-year backtest shows a typical error of ±27.2%, with 100% of held-out values landing inside the 95% band.

+52%Change by 2029
1.3Projected 2029 index
0.00–3.395% range
±27.2%Backtest error
19682029
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
20251.30.003.4
20261.30.003.4
20271.30.003.4
20281.30.003.4
20291.30.003.3

Routes In Sierra Madre Occidental

Routes recording Vesper Sparrow in Sierra Madre Occidental.
AlpineARIZONA152023
MaineARIZONA122024
PinetopARIZONA112022
FlagstaffARIZONA92022
Mormon LakeARIZONA51975
Clay SpringARIZONA52021
WilliamsARIZONA42019
SprucedaleARIZONA42023
Happy JackARIZONA32024
BlueARIZONA11985
Forest LakesARIZONA12022

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