BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Magnolia Warbler Population Analysis

ParulidaeForest birdsSetophaga magnolia

Magnolia Warbler has held roughly steady: up 4% on the route-weighted index since 1968.

+4%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 →
464RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Magnolia Warbler

The Magnolia Warbler (Setophaga magnolia) is a North American member of the Wood-Warblers (Parulidae). In this analysis it is grouped with the forest birds.

Size
4.5–5.5 in long (11–14 cm) — a small, active songbird (typical for the family)
Habitat
Woodlands and forest edges, including wooded suburbs and parks.
Diet
Insects and spiders gleaned from foliage and bark, with seeds and berries in season.
Range
Recorded on 464 Breeding Bird Survey routes across 16 states, most concentrated in the Atlantic Northern Forest.
Family
Parulidae · Forest birds

Notable Magnolia Warbler TrendsNotable 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. See the full index history below.

Magnolia Warbler Population Forecast

If the recent trend holds, Magnolia Warbler is projected to rise about 39% by 2030 — from 0.21 in 2025 to a central estimate of 0.29 (95% range 0.17–0.42). A 5-year backtest shows a typical error of ±66.3%, with 0% of held-out values landing inside the 95% band.

+39%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 →
0.29Projected 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 →
0.17–0.4295% 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 →
±66.3%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 is projected to rise about 39% by 2030 — from 0.21 in 2025 to a central estimate of 0.29 (95% range 0.17–0.42). A 5-year backtest shows a typical error of ±66.3%, with 0% 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 →
20260.290.160.42
20270.290.160.42
20280.290.170.42
20290.290.170.42
20300.290.170.42

Where the Magnolia Warbler Is Detected

BBS routes recording Magnolia Warbler, sized by most recent count.

Magnolia Warbler Population Trend by State

Magnolia Warbler population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Connecticut+11%19749
Maine-63%196974
Maryland+472%19688
Massachusetts-41%197017
Michigan12×197452
Minnesota+313%196931
New Hampshire-38%196825
New Jerseyinsufficient datan/a3
New York-47%196888
North Carolinainsufficient datan/a1
Ohioinsufficient datan/a2
Pennsylvania+579%196872
Vermont+200%196824
Virginiainsufficient datan/a2
West Virginia+945%196920
Wisconsin+332%196936

Magnolia Warbler Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Magnolia Warbler population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Boreal Hardwood Transition+578%1968103
Lower Great Lakes / St. Lawrence Plain-46%196841
Atlantic Northern Forest-28%1968150
Prairie Hardwood Transition-35%198016
Appalachian Mountains+625%1968132
New England / Mid-Atlantic Coast-3%196922

Magnolia Warbler Conservation Status

Our route-weighted index shows it up about 4% since 1968.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.