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

Common Merganser In Appalachian Mountains

All regionsAppalachian MountainsWaterfowl

Common Merganser in Appalachian Mountains has surged: up 19× on the route-weighted index since 1977.

19×Since 1977
99Routes In Region
48Years

Notable Signals

long arc increasecomputed index

Common Merganser has surged in Appalachian Mountains: up 19× on the route-weighted index since 1977.

Forecast

If the recent trend holds, Common Merganser in Appalachian Mountains is projected to rise about 33% by 2029 — from 0.14 in 2024 to a central estimate of 0.19 (95% range 0.01–0.37). A 5-year backtest shows a typical error of ±51.5%, with 100% of held-out values landing inside the 95% band.

+33%Change by 2029
0.19Projected 2029 index
0.01–0.3795% range
±51.5%Backtest error
19712029
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
20250.180.000.36
20260.180.000.36
20270.180.000.36
20280.190.010.37
20290.190.010.37

Routes In Appalachian Mountains

Routes recording Common Merganser in Appalachian Mountains.
StollingsWEST-VIRGINIA122018
Natural BridVIRGINIA102023
RushPENNSYLVANIA92024
BerwickPENNSYLVANIA91993
EldredPENNSYLVANIA82015
Pocono SummitPENNSYLVANIA82024
LisleNEW-YORK62007
OneontaNEW-YORK52023
SusquehannaPENNSYLVANIA42023
Yellow SpgWEST-VIRGINIA42018
JenningsMARYLAND32024
LynchPENNSYLVANIA32019
RasselasPENNSYLVANIA32014
ArnotPENNSYLVANIA32004
WallerPENNSYLVANIA32018
KittanningPENNSYLVANIA32019
New RinggoldPENNSYLVANIA32012
WyalusingPENNSYLVANIA32022
WilliamsportMARYLAND22022
CobleskillNEW-YORK22015
LaurensNEW-YORK22024
CentervilleNEW-YORK22005
S VandaliaNEW-YORK22016
BetulaPENNSYLVANIA22019
RoulettePENNSYLVANIA22008

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