BirdAnalyst
Species · BCR 13 · BBS 2026 Release · 1966–2025

Magnolia Warbler In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainForest birds

Magnolia Warbler in Lower Great Lakes / St. Lawrence Plain has declined: down 46% on the route-weighted index since 1968.

-46%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 →
41Routes 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 →
58YearsYears 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 Magnolia Warbler in Lower Great Lakes / St. Lawrence Plain. See the full index history below.

Magnolia Warbler In Lower Great Lakes / St. Lawrence Plain Population Forecast

If the recent trend holds, Magnolia Warbler in Lower Great Lakes / St. Lawrence Plain is projected to rise about 80% by 2030 — from 0.11 in 2025 to a central estimate of 0.19 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±236.4%, with 100% of held-out values landing inside the 95% band.

+80%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 →
0.19Projected 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 →
0.00–0.4295% 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 →
±236.4%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, Magnolia Warbler in Lower Great Lakes / St. Lawrence Plain is projected to rise about 80% by 2030 — from 0.11 in 2025 to a central estimate of 0.19 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±236.4%, 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 →
20260.200.000.43
20270.200.000.42
20280.200.000.42
20290.190.000.42
20300.190.000.42

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording Magnolia Warbler in Lower Great Lakes / St. Lawrence Plain.
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 →
BalmatNEW-YORK51997
RandolphNEW-YORK32018
N WilmurtNEW-YORK31998
WillsboroNEW-YORK32000
CatskillsNEW-YORK22004
SheridanNEW-YORK22025
Cherry HillNEW-YORK22014
TeeplevillePENNSYLVANIA22005
HarrisvillePENNSYLVANIA22025
HighlandNEW-YORK12010
W ShokanNEW-YORK12019
AusterlitzNEW-YORK11992
DuanesburgNEW-YORK12000
Oriskany FlsNEW-YORK11992
RomulusNEW-YORK11997
TrumansburgNEW-YORK12022
BranchportNEW-YORK12018
Canadice LNEW-YORK12023
MendonNEW-YORK11989
Mt MorrisNEW-YORK12024
CastileNEW-YORK12010
NashvilleNEW-YORK12012
PulaskiNEW-YORK12022
Alder CreekNEW-YORK12004
OneidaNEW-YORK11997

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