BirdAnalyst
Species · Pennsylvania · BBS 2026 Release · 1966–2025

Magnolia Warbler Population Trend in Pennsylvania

All statesForest birds

Magnolia Warbler in Pennsylvania has surged: up 579% on the route-weighted index since 1968.

+579%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 →
72Routes 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 →
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 Magnolia Warbler Trends in PennsylvaniaNotable 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 →

Magnolia Warbler has surged in Pennsylvania: up 579% on the route-weighted index since 1968.

Magnolia Warbler Population Forecast in Pennsylvania

If the recent trend holds, Magnolia Warbler in Pennsylvania is projected to rise about 51% by 2030 — from 0.78 in 2025 to a central estimate of 1.2 (95% range 0.82–1.5). A 5-year backtest shows a typical error of ±51.6%, with 20% of held-out values landing inside the 95% band.

+51%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 →
1.2Projected 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 →
0.82–1.595% 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 →
±51.6%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 Pennsylvania is projected to rise about 51% by 2030 — from 0.78 in 2025 to a central estimate of 1.2 (95% range 0.82–1.5). A 5-year backtest shows a typical error of ±51.6%, with 20% 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 →
20261.10.751.5
20271.10.771.5
20281.10.791.5
20291.20.801.5
20301.20.821.5

Magnolia Warbler Survey Routes in Pennsylvania

Routes recording Magnolia Warbler in Pennsylvania.
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 →
Logue1220251970
Mawr Glen720251982
Ridgway620181994
Eldred620221973
Marsh Hill620251985
N Pine Grove520251975
Cherry Sprs520251974
Susquehanna520251992
Honesdale420171973
Starlight419991997
Pocono Summit 2420062004
Ellenton320251984
Roulette320211975
Little Marsh320242005
Laurel Hill320241978
Hometown319921992
Ansonia320252002
Roulette 2320252022
Whig Hill220251966
Teepleville220052005
Lynch220251969
Russell City220251968
Rasselas220221969
English Ctr219891989
Bow Bridge220241983

Magnolia Warbler Population Trend in Other States

connecticutmainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinaohiovermontvirginiawest-virginiawisconsin

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