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

Barn Swallow In Southeastern Coastal Plain

All regionsSoutheastern Coastal PlainAerial insectivores

Barn Swallow in Southeastern Coastal Plain has surged: up 147% on the route-weighted index since 1968.

+147%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 →
334Routes 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 →

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 →

Barn Swallow has surged in Southeastern Coastal Plain: up 147% on the route-weighted index since 1968.

Barn Swallow In Southeastern Coastal Plain Population Forecast

If the recent trend holds, Barn Swallow in Southeastern Coastal Plain is projected to rise about 15% by 2030 — from 13 in 2025 to a central estimate of 15 (95% range 11–18). A 5-year backtest shows a typical error of ±20.6%, with 80% of held-out values landing inside the 95% band.

+15%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 →
15Projected 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 →
11–1895% 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 →
±20.6%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, Barn Swallow in Southeastern Coastal Plain is projected to rise about 15% by 2030 — from 13 in 2025 to a central estimate of 15 (95% range 11–18). A 5-year backtest shows a typical error of ±20.6%, with 80% 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 →
2026141118
2027141118
2028151118
2029151118
2030151118

Routes In Southeastern Coastal Plain

Routes recording Barn Swallow 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 →
Wards CornerNORTH-CAROLINA1492024
HumboldtTENNESSEE1002025
HarrellALABAMA752025
WhitevilleTENNESSEE742025
ShilohGEORGIA662025
SpeedNORTH-CAROLINA612025
Cypress CrNORTH-CAROLINA502022
PinewoodSOUTH-CAROLINA492019
BackbayVIRGINIA431974
OwensboroGEORGIA392025
LovelacevileKENTUCKY382025
GenoaNORTH-CAROLINA362025
OusleyGEORGIA352025
CyburMISSISSIPPI342019
CottonGEORGIA332025
ColumbiaMISSISSIPPI332018
Leaf RiverMISSISSIPPI332013
Holly HillSOUTH-CAROLINA332025
LakeMISSISSIPPI322025
MaconMISSISSIPPI322025
MansfieldTENNESSEE322025
NashvilleGEORGIA312025
DortchesNORTH-CAROLINA312025
DillonSOUTH-CAROLINA312021
LibertyALABAMA302022

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