BirdAnalyst
Species · BCR 29 · BBS 2026 Release · 1966–2025

Cliff Swallow In Piedmont

All regionsPiedmontAerial insectivores

Cliff Swallow in Piedmont has surged: up 21× on the route-weighted index since 1970.

21×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 →
73Routes 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 →
57YearsYears 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 →

Cliff Swallow has surged in Piedmont: up 21× on the route-weighted index since 1970.

Cliff Swallow In Piedmont Population Forecast

If the recent trend holds, Cliff Swallow in Piedmont is projected to stay roughly flat through 2030, near 4.2 (95% range 1.9–6.5). A 5-year backtest shows a typical error of ±50.3%, with 100% of held-out values landing inside the 95% band.

-5%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 →
4.2Projected 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 →
1.9–6.595% 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 →
±50.3%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, Cliff Swallow in Piedmont is projected to stay roughly flat through 2030, near 4.2 (95% range 1.9–6.5). A 5-year backtest shows a typical error of ±50.3%, with 100% 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 →
20263.91.66.2
20274.01.76.2
20284.01.76.3
20294.11.86.4
20304.21.96.5

Routes In Piedmont

Routes recording Cliff Swallow in Piedmont.
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 →
WylliesburgVIRGINIA2202019
ArcolaNORTH-CAROLINA932025
FairviewNORTH-CAROLINA702025
CallNORTH-CAROLINA542025
RidgewaySOUTH-CAROLINA522021
BlacksburgSOUTH-CAROLINA452013
SiloamGEORGIA302024
HebronGEORGIA302021
GladysVIRGINIA182025
Owings 2SOUTH-CAROLINA172025
Nixburg 2ALABAMA152025
EdenNORTH-CAROLINA152025
Plum BranchSOUTH-CAROLINA142025
BrodnaxVIRGINIA142025
WhitesburgGEORGIA132025
Curry HillGEORGIA132017
WoodstockGEORGIA132021
SiloamNORTH-CAROLINA132025
Rock BranchGEORGIA122025
MillervilleALABAMA82024
FinchleyVIRGINIA82021
JulietteGEORGIA72016
CrestGEORGIA62022
EkloMARYLAND62017
West GrovePENNSYLVANIA61992

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