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Species · Arkansas · BBS 2026 Release · 1966–2025

Swainson's Warbler Population Trend in Arkansas

All statesForest birds

Swainson's Warbler in Arkansas has surged: up 158% on the route-weighted index since 1970.

+158%Since 1970TrendPercent 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 →
15Routes 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 →
37YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Swainson's Warbler Trends in ArkansasNotable 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 →

Swainson's Warbler has surged in Arkansas: up 158% on the route-weighted index since 1970.

Swainson's Warbler Population Forecast in Arkansas

If the recent trend holds, Swainson's Warbler in Arkansas is projected to rise about 64% by 2030 — from 0.18 in 2025 to a central estimate of 0.29 (95% range 0.09–0.50). A 5-year backtest shows a typical error of ±52.8%, with 100% of held-out values landing inside the 95% band.

+64%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 →
0.09–0.5095% 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 →
±52.8%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, Swainson's Warbler in Arkansas is projected to rise about 64% by 2030 — from 0.18 in 2025 to a central estimate of 0.29 (95% range 0.09–0.50). A 5-year backtest shows a typical error of ±52.8%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.270.070.48
20270.280.070.48
20280.280.080.49
20290.290.080.49
20300.290.090.50

Swainson's Warbler Survey Routes in Arkansas

Routes recording Swainson's Warbler in Arkansas.
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 →
Old Milo220251969
Ramsey119941968
Locust Bayou120231989
Hope120252019
Havana120152015
Princeton120012001
Four Lakes120002000
South Bend119771977
Gillett120242024
Poyen120071970
Hollywood120141982
Blakely119991990
Crowley'S Ridge120252011
Poyen 2120252008
Dry Fork120062006

Swainson's Warbler Population Trend in Other States

alabamafloridageorgiakentuckylouisianamarylandmississippinorth-carolinaoklahomasouth-carolinatennesseetexasvirginiawest-virginia

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