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Species · BCR 14 · BBS 2026 Release · 1966–2025

Ruby-crowned Kinglet In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Ruby-crowned Kinglet in Atlantic Northern Forest has fallen sharply: down 73% on the route-weighted index since 1968.

-73%Since 1968TrendPercent 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 →
112Routes 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 →
59YearsYears 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 declinecomputed 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 fallen sharply in Atlantic Northern Forest: down 73% on the route-weighted index since 1968.

Ruby-crowned Kinglet In Atlantic Northern Forest Population Forecast

If the recent trend holds, Ruby-crowned Kinglet in Atlantic Northern Forest is projected to rise about 74% by 2030 — from 0.12 in 2025 to a central estimate of 0.20 (95% range 0.00–0.82). A 5-year backtest shows a typical error of ±60.8%, with 100% of held-out values landing inside the 95% band.

+74%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 →
0.20Projected 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 →
0.00–0.8295% 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 →
±60.8%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, Ruby-crowned Kinglet in Atlantic Northern Forest is projected to rise about 74% by 2030 — from 0.12 in 2025 to a central estimate of 0.20 (95% range 0.00–0.82). A 5-year backtest shows a typical error of ±60.8%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.240.000.86
20270.230.000.85
20280.220.000.84
20290.210.000.83
20300.200.000.82

Routes In Atlantic Northern Forest

Routes recording Ruby-crowned Kinglet in Atlantic Northern Forest.
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 →
Big TwentyMAINE172008
Pillsbury PdMAINE111968
YankeetuladiMAINE92009
Big Twenty 2MAINE92009
Moose RiverMAINE52008
Weeks BrookMAINE52016
Lake MoxieMAINE52010
Wilson MillsMAINE42025
Otisfield GrMAINE31975
Bowdoin CtrMAINE31975
HarmonyMAINE31996
BentonMAINE31980
NorthfieldMAINE31981
Seboomook LkMAINE32014
St DavidMAINE32005
Northfield 2MAINE31998
Dixvil NotchNEW-HAMPSHIRE32017
NewcombNEW-YORK32013
BethelMAINE21977
GreenwoodMAINE22005
South ArmMAINE21999
HermonMAINE21992
HancockMAINE21987
AuroraMAINE21998
Grnd Lk StrmMAINE21999

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