BirdAnalyst
Species · BCR 34 · BBS 2026 Release · 1966–2025

Verdin In Sierra Madre Occidental

All regionsSierra Madre OccidentalArid-land birds

Verdin in Sierra Madre Occidental has held roughly steady: down 5% on the route-weighted index since 1970.

-5%Since 1970TrendPercent 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 →
20Routes 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 →
57YearsYears 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 Verdin in Sierra Madre Occidental. See the full index history below.

Verdin In Sierra Madre Occidental Population Forecast

If the recent trend holds, Verdin in Sierra Madre Occidental is projected to rise about 17% by 2030 — from 5.3 in 2025 to a central estimate of 6.2 (95% range 1.5–11). A 5-year backtest shows a typical error of ±83.3%, with 80% of held-out values landing inside the 95% band.

+17%Change by 2030TrendPercent 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 →
6.2Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
1.5–1195% 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 →
±83.3%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, Verdin in Sierra Madre Occidental is projected to rise about 17% by 2030 — from 5.3 in 2025 to a central estimate of 6.2 (95% range 1.5–11). A 5-year backtest shows a typical error of ±83.3%, with 80% of held-out values landing inside the 95% band.19682030
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 →
20266.21.511
20276.21.511
20286.21.511
20296.21.511
20306.21.511

Routes In Sierra Madre Occidental

Routes recording Verdin in Sierra Madre Occidental.
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 →
PomereneARIZONA642025
CutterARIZONA602014
SahuaritaARIZONA212025
Aztec PeakARIZONA151978
Bartlett ResARIZONA142025
RedingtonARIZONA142025
Carr MtnARIZONA122025
SunizonaARIZONA71997
PortalARIZONA52025
Peña BlancaARIZONA42025
PatagoniaARIZONA42025
AmadoARIZONA32025
San SimonARIZONA22024
McnealARIZONA22025
DragoonARIZONA22009
RuckerARIZONA22003
Vicks PeakNEW-MEXICO22022
Skull ValleyARIZONA12018
Sunizona 2ARIZONA12023
MagdalenaNEW-MEXICO12022

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.