BirdAnalyst
Species · BCR 29 · BBS 2025 Release · 1966–2024

Cliff Swallow In Piedmont

All regionsPiedmontAerial insectivores

Cliff Swallow in Piedmont has surged: up 18× on the route-weighted index since 1970.

18×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 →
70Routes 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 →
56YearsYears 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 18× on the route-weighted index since 1970.

Forecast

If the recent trend holds, Cliff Swallow in Piedmont is projected to stay roughly flat through 2029, near 4.1 (95% range 1.8–6.3). A 5-year backtest shows a typical error of ±51.2%, with 80% of held-out values landing inside the 95% band.

-6%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 →
4.1Projected 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 →
1.8–6.395% 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 →
±51.2%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 2029, near 4.1 (95% range 1.8–6.3). A 5-year backtest shows a typical error of ±51.2%, 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 →
20253.81.56.1
20263.81.56.1
20273.91.66.2
20284.01.76.3
20294.11.86.3

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
CallNORTH-CAROLINA912024
WhitesburgGEORGIA882024
Rock BranchGEORGIA762022
RidgewaySOUTH-CAROLINA522021
BlacksburgSOUTH-CAROLINA452013
ArcolaNORTH-CAROLINA312024
SiloamGEORGIA302024
HebronGEORGIA302021
CopelandNORTH-CAROLINA202024
SiloamNORTH-CAROLINA192024
Plum BranchSOUTH-CAROLINA162024
FairviewNORTH-CAROLINA142024
Curry HillGEORGIA132017
WoodstockGEORGIA132021
Mooresville 2NORTH-CAROLINA102024
Owings 2SOUTH-CAROLINA102024
BrodnaxVIRGINIA102024
MillervilleALABAMA82024
FinchleyVIRGINIA82021
JulietteGEORGIA72016
CrestGEORGIA62022
EkloMARYLAND62017
OakboroNORTH-CAROLINA62024
West GrovePENNSYLVANIA61992

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