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

Ruby-crowned Kinglet In Sierra Madre Occidental

All regionsSierra Madre OccidentalForest birds

Ruby-crowned Kinglet in Sierra Madre Occidental has surged: up 656% on the route-weighted index since 1975.

+656%Since 1975TrendPercent 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 →
12Routes 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 →
46YearsYears 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 →

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 →

Ruby-crowned Kinglet has surged in Sierra Madre Occidental: up 656% on the route-weighted index since 1975.

Ruby-crowned Kinglet In Sierra Madre Occidental Population Forecast

If the recent trend holds, Ruby-crowned Kinglet in Sierra Madre Occidental is projected to stay roughly flat through 2028, near 1.8 (95% range 0.42–3.1). A 5-year backtest shows a typical error of ±38.7%, with 100% of held-out values landing inside the 95% band.

-5%Change 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 →
1.8Projected 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 →
0.42–3.195% 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 →
±38.7%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, Ruby-crowned Kinglet in Sierra Madre Occidental is projected to stay roughly flat through 2028, near 1.8 (95% range 0.42–3.1). A 5-year backtest shows a typical error of ±38.7%, with 100% of held-out values landing inside the 95% band.19682028
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 →
20241.70.323.0
20251.70.343.0
20261.70.373.0
20271.70.403.1
20281.80.423.1

Routes In Sierra Madre Occidental

Routes recording Ruby-crowned Kinglet 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 →
AlpineARIZONA342023
MaineARIZONA91997
SprucedaleARIZONA82010
Mt. GrahamARIZONA72023
BlueARIZONA31991
Happy JackARIZONA22004
FlagstaffARIZONA12013
Mormon LakeARIZONA11968
WilliamsARIZONA11993
PinetopARIZONA12018
PortalARIZONA11975
Emory PassNEW-MEXICO12000

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