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

Tree Swallow In Appalachian Mountains

Tree Swallow in Appalachian Mountains has surged: up 236% on the route-weighted index since 1968.

+236%Since 1968
339Routes In Region
58Years

Notable Signals

long arc increasecomputed index

Tree Swallow has surged in Appalachian Mountains: up 236% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Tree Swallow in Appalachian Mountains is projected to rise about 54% by 2029 — from 2.9 in 2024 to a central estimate of 4.5 (95% range 3.1–5.9). A 5-year backtest shows a typical error of ±62.8%, with 0% of held-out values landing inside the 95% band.

+54%Change by 2029
4.5Projected 2029 index
3.15.995% range
±62.8%Backtest error
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 index95% low95% high
20254.32.95.7
20264.43.05.8
20274.43.05.8
20284.53.15.9
20294.53.15.9

Routes In Appalachian Mountains

Routes recording Tree Swallow in Appalachian Mountains.
WelchWEST-VIRGINIA352022
Brunnerville 2PENNSYLVANIA292024
RydePENNSYLVANIA272005
McdonoughNEW-YORK262017
Clear CreekWEST-VIRGINIA262024
SmithsburgMARYLAND252013
DurhamNEW-YORK251976
S BerneNEW-YORK212013
SwainNEW-YORK202007
BetulaPENNSYLVANIA202022
GuntersvilleALABAMA192017
SturgillsNORTH-CAROLINA172024
DrydenNEW-YORK162024
SusquehannaPENNSYLVANIA162024
Phillips CrNEW-YORK152024
BirminghamOHIO152019
BrevardNORTH-CAROLINA132024
HometownPENNSYLVANIA132024
BlacksburgVIRGINIA132024
GhentWEST-VIRGINIA132024
ClendeninWEST-VIRGINIA132024
LisleNEW-YORK122022
Vestal CtrNEW-YORK122019
EllentonPENNSYLVANIA122024
Iron Mtn.VIRGINIA122011

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