BirdAnalyst
Species · BCR 27 · BBS 2026 Release · 1966–2025

Swainson's Warbler In Southeastern Coastal Plain

All regionsSoutheastern Coastal PlainForest birds

Swainson's Warbler in Southeastern Coastal Plain has surged: up 34× on the route-weighted index since 1968.

34×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 →
220Routes 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 →

No notable trend signals for Swainson's Warbler in Southeastern Coastal Plain. See the full index history below.

Swainson's Warbler In Southeastern Coastal Plain Population Forecast

If the recent trend holds, Swainson's Warbler in Southeastern Coastal Plain is projected to fall about 43% by 2030 — from 0.98 in 2025 to a central estimate of 0.56 (95% range 0.38–0.73). A 5-year backtest shows a typical error of ±22.1%, with 60% of held-out values landing inside the 95% band.

-43%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 →
0.56Projected 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 →
0.38–0.7395% 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 →
±22.1%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, Swainson's Warbler in Southeastern Coastal Plain is projected to fall about 43% by 2030 — from 0.98 in 2025 to a central estimate of 0.56 (95% range 0.38–0.73). A 5-year backtest shows a typical error of ±22.1%, with 60% 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 →
20260.520.340.70
20270.530.350.71
20280.540.360.72
20290.550.370.72
20300.560.380.73

Routes In Southeastern Coastal Plain

Routes recording Swainson's Warbler in Southeastern Coastal 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 →
Sprott-Cahaba RivALABAMA342014
GreensboroALABAMA212025
Gainestown FerryALABAMA172015
CarrolltonALABAMA112025
JenaALABAMA82025
Seminole Hills 2FLORIDA72022
BloctonALABAMA62025
New HopeFLORIDA62011
WedgeworthALABAMA52025
HoltALABAMA52025
HeliconALABAMA52025
WorkmoreGEORGIA52025
Trace LormanMISSISSIPPI52019
Dismal SwampNORTH-CAROLINA52024
LindenALABAMA42023
Warrior StdALABAMA42025
NewtonALABAMA42024
BloxhamFLORIDA42022
CuthbertGEORGIA42025
CottonGEORGIA42025
LacrossGEORGIA42025
TazewellGEORGIA42025
DeepstepGEORGIA42023
Green SeaSOUTH-CAROLINA42025
Dismal SwampVIRGINIA42016

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