BirdAnalyst
Species · BCR 28 · BBS 2025 Release · 1966–2024

Purple Martin In Appalachian Mountains

All regionsAppalachian MountainsAerial insectivores

Purple Martin in Appalachian Mountains has fallen sharply: down 64% on the route-weighted index since 1968.

-64%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 →
272Routes 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 declinecomputed 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 →

Purple Martin has fallen sharply in Appalachian Mountains: down 64% on the route-weighted index since 1968.

Purple Martin In Appalachian Mountains Population Forecast

If the recent trend holds, Purple Martin in Appalachian Mountains is projected to fall about 52% by 2029 — from 2.0 in 2024 to a central estimate of 0.98 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±43.9%, with 100% of held-out values landing inside the 95% band.

-52%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 →
0.98Projected 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 →
0.00–2.495% 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 →
±43.9%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 Appalachian Mountains is projected to fall about 52% by 2029 — from 2.0 in 2024 to a central estimate of 0.98 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±43.9%, with 100% 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 →
20251.10.002.6
20261.10.002.5
20271.10.002.5
20281.00.002.4
20290.980.002.4

Routes In Appalachian Mountains

Routes recording Purple Martin in Appalachian Mountains.
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 →
DresdenOHIO632024
Signal MtnTENNESSEE422024
DearmanvilleALABAMA371980
ClinchportVIRGINIA341978
Bald EaglePENNSYLVANIA302024
Peters MtPENNSYLVANIA271976
SummittALABAMA251981
WallandTENNESSEE251987
WoodvilleALABAMA242024
Amos MillGEORGIA242022
LandisburgPENNSYLVANIA212024
OakmanGEORGIA202024
WilgusOHIO202009
LovellTENNESSEE202019
LakeviewALABAMA182024
JasperALABAMA181999
Davis CrossroadsGEORGIA182021
RiversideALABAMA172013
MckeeKENTUCKY162024
Jonas RidgeNORTH-CAROLINA161971
KeeneOHIO152023
Mt OliveALABAMA142024
MaytownALABAMA142023
East JavaNEW-YORK141973
Borden SprngALABAMA131998

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