Species · BCR 12 · BBS 2025 Release · 1966–2024

Common Merganser In Boreal Hardwood Transition

Common Merganser in Boreal Hardwood Transition has surged: up 113% on the route-weighted index since 1973.

+113%Since 1973
63Routes In Region
46Years

Notable Signals

long arc increasecomputed index

Common Merganser has surged in Boreal Hardwood Transition: up 113% on the route-weighted index since 1973.

Forecast

If the recent trend holds, Common Merganser in Boreal Hardwood Transition is projected to rise about 72% by 2029 — from 0.05 in 2024 to a central estimate of 0.09 (95% range 0.00–0.19). A 5-year backtest shows a typical error of ±172.7%, with 100% of held-out values landing inside the 95% band.

+72%Change by 2029
0.09Projected 2029 index
0.000.1995% range
±172.7%Backtest error
19672029
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
20250.090.000.18
20260.090.000.19
20270.090.000.19
20280.090.000.19
20290.090.000.19

Routes In Boreal Hardwood Transition

Routes recording Common Merganser in Boreal Hardwood Transition.
Red OakMICHIGAN72011
Wigwam BayMINNESOTA62018
Hiawatha NfMICHIGAN42013
CohassetMINNESOTA32021
BabbittMINNESOTA32022
McnaughtonWISCONSIN32013
BerglandMICHIGAN21990
Bear LakeMICHIGAN22011
OberlinMICHIGAN21994
Sand LakeMICHIGAN21996
GilmanWISCONSIN22004
CrandonWISCONSIN22018
MareniscoMICHIGAN11994
Ned LakeMICHIGAN12014
HermanMICHIGAN12022
Crystal FlsMICHIGAN12009
Gibbs CityMICHIGAN12013
Maple GroveMICHIGAN12017
IshpemingMICHIGAN12021
WilsonMICHIGAN12008
CunardMICHIGAN11997
MuskallongeMICHIGAN12013
GilchristMICHIGAN11997
Lake CityMICHIGAN11978
Skegemog PtMICHIGAN12023

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