BirdAnalyst
Species · BCR 27 · BBS 2025 Release · 1966–2024

Barn Swallow In Southeastern Coastal Plain

All regionsSoutheastern Coastal PlainAerial insectivores

Barn Swallow in Southeastern Coastal Plain has surged: up 146% on the route-weighted index since 1968.

+146%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 →
333Routes 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 →
58YearsYears 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 146% 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 17% by 2029 — from 13 in 2024 to a central estimate of 15 (95% range 11–18). A 5-year backtest shows a typical error of ±24.7%, with 80% of held-out values landing inside the 95% band.

+17%Change by 2029TrendPercent 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 2029 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 →
±24.7%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 17% by 2029 — from 13 in 2024 to a central estimate of 15 (95% range 11–18). A 5-year backtest shows a typical error of ±24.7%, with 80% of held-out values landing inside the 95% band.19662029
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 →
2025141118
2026151118
2027151118
2028151118
2029151118

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
HendersonGEORGIA622024
ShilohGEORGIA532024
NewtonGEORGIA522024
Cypress CrNORTH-CAROLINA502022
PinewoodSOUTH-CAROLINA492019
CottonGEORGIA462024
BackbayVIRGINIA431974
OwensboroGEORGIA422024
SpeedNORTH-CAROLINA422024
GenoaNORTH-CAROLINA402024
Holly HillSOUTH-CAROLINA402024
WhitevilleTENNESSEE392024
TazewellGEORGIA382024
FinleysonGEORGIA382024
New HollandSOUTH-CAROLINA382024
MansfieldTENNESSEE362024
CyburMISSISSIPPI342019
HumboldtTENNESSEE342024
WeberGEORGIA332024
ColumbiaMISSISSIPPI332018
Leaf RiverMISSISSIPPI332013
DillonSOUTH-CAROLINA312021
HowardALABAMA302024
LibertyALABAMA302022

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.