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

Purple Martin In Piedmont

All regionsPiedmontAerial insectivores

Purple Martin in Piedmont has declined: down 37% on the route-weighted index since 1968.

-37%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 →
167Routes 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 →

No notable trend signals for Purple Martin in Piedmont. See the full index history below.

Purple Martin In Piedmont Population Forecast

If the recent trend holds, Purple Martin in Piedmont is projected to rise about 25% by 2030 — from 4.7 in 2025 to a central estimate of 5.9 (95% range 0.57–11). A 5-year backtest shows a typical error of ±44.6%, with 100% of held-out values landing inside the 95% band.

+25%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 →
5.9Projected 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 →
0.57–1195% 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 →
±44.6%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, Purple Martin in Piedmont is projected to rise about 25% by 2030 — from 4.7 in 2025 to a central estimate of 5.9 (95% range 0.57–11). A 5-year backtest shows a typical error of ±44.6%, 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 →
20266.00.6811
20276.00.6511
20286.00.6211
20296.00.6011
20305.90.5711

Routes In Piedmont

Routes recording Purple Martin 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 →
BlacksburgSOUTH-CAROLINA3122013
MetasvilleGEORGIA652000
Little MtnSOUTH-CAROLINA581988
ProsperitySOUTH-CAROLINA532024
WedoweeALABAMA352023
Barton CreekSOUTH-CAROLINA292022
FlayNORTH-CAROLINA282025
Nixburg 2ALABAMA272024
LeolaPENNSYLVANIA232025
HiramGEORGIA222018
RutledgeGEORGIA212025
OakboroNORTH-CAROLINA212025
WhitesburgGEORGIA202025
JordanNORTH-CAROLINA202025
MadonnaMARYLAND192022
TaylorstownVIRGINIA182010
PendletonSOUTH-CAROLINA161976
FairplayGEORGIA151990
WacoNORTH-CAROLINA152019
Salem XrdSOUTH-CAROLINA152017
BullockNORTH-CAROLINA142025
LanettALABAMA132024
BendersvillePENNSYLVANIA132024
Plum BranchSOUTH-CAROLINA132025
RinggoldVIRGINIA132025

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