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

Great Blue Heron In Sierra Madre Occidental

All regionsSierra Madre OccidentalWetland birds

Great Blue Heron in Sierra Madre Occidental has edged up: up 23% on the route-weighted index since 1978.

+23%Since 1978TrendPercent 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 →
23Routes 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 →
45YearsYears 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 Great Blue Heron in Sierra Madre Occidental. See the full index history below.

Great Blue Heron In Sierra Madre Occidental Population Forecast

If the recent trend holds, Great Blue Heron in Sierra Madre Occidental is projected to rise about 227% by 2029 — from 0.11 in 2024 to a central estimate of 0.36 (95% range 0.00–2.6). A 5-year backtest shows a typical error of ±304.8%, with 100% of held-out values landing inside the 95% band.

+227%Change by 2029TrendPercent 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 →
0.36Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–2.695% 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 →
±304.8%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, Great Blue Heron in Sierra Madre Occidental is projected to rise about 227% by 2029 — from 0.11 in 2024 to a central estimate of 0.36 (95% range 0.00–2.6). A 5-year backtest shows a typical error of ±304.8%, with 100% of held-out values landing inside the 95% band.19752029
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 →
20250.390.002.6
20260.390.002.6
20270.380.002.6
20280.370.002.6
20290.360.002.6

Routes In Sierra Madre Occidental

Routes recording Great Blue Heron 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 →
PatagoniaARIZONA42017
CutterARIZONA32014
PrescottARIZONA22016
Tonto Vill.ARIZONA22021
Bartlett ResARIZONA22022
Happy JackARIZONA22022
SprucedaleARIZONA21998
PomereneARIZONA12024
San SimonARIZONA11984
Peña BlancaARIZONA12005
WilliamsARIZONA12018
MaineARIZONA12011
Skull ValleyARIZONA12024
Forest LakesARIZONA12022
PinetopARIZONA12004
AlpineARIZONA12023
RedingtonARIZONA12010
AmadoARIZONA12012
McnealARIZONA12015
Clay SpringARIZONA12014
Carr MtnARIZONA12023
Sunizona 2ARIZONA12017
ReserveNEW-MEXICO12009

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