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Species · Arizona · BBS 2025 Release · 1966–2024

Ridgway's Rail Population Trend in Arizona

All statesWetland birds

Ridgway's Rail in Arizona has surged: up 239% on the route-weighted index since 1997.

+239%Since 1997TrendPercent 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 →
4Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
22YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Ridgway's Rail Trends in ArizonaNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Ridgway's Rail has surged in Arizona: up 239% on the route-weighted index since 1997.

Ridgway's Rail Population Forecast in Arizona

If the recent trend holds, Ridgway's Rail in Arizona is projected to stay roughly flat through 2028, near 0.16 (95% range 0.04–0.28). A 5-year backtest shows a typical error of ±70.1%, with 60% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.16Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.04–0.2895% 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 →
±70.1%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, Ridgway's Rail in Arizona is projected to stay roughly flat through 2028, near 0.16 (95% range 0.04–0.28). A 5-year backtest shows a typical error of ±70.1%, with 60% of held-out values landing inside the 95% band.19932028
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 →
20240.150.020.27
20250.150.030.27
20260.150.030.28
20270.160.040.28
20280.160.040.28

Ridgway's Rail Survey Routes in Arizona

Routes recording Ridgway's Rail in Arizona.
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 →
Araby420221993
Cibola Lake320212016
Laguna220102010
Palo Verde 2220232023

Ridgway's Rail Population Trend in Other States

californianevada

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