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
0.00–0.1995% range
±172.7%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.09 | 0.00 | 0.18 |
| 2026 | 0.09 | 0.00 | 0.19 |
| 2027 | 0.09 | 0.00 | 0.19 |
| 2028 | 0.09 | 0.00 | 0.19 |
| 2029 | 0.09 | 0.00 | 0.19 |
Routes In Boreal Hardwood Transition
| Red Oak | MICHIGAN | 7 | 2011 |
| Wigwam Bay | MINNESOTA | 6 | 2018 |
| Hiawatha Nf | MICHIGAN | 4 | 2013 |
| Cohasset | MINNESOTA | 3 | 2021 |
| Babbitt | MINNESOTA | 3 | 2022 |
| Mcnaughton | WISCONSIN | 3 | 2013 |
| Bergland | MICHIGAN | 2 | 1990 |
| Bear Lake | MICHIGAN | 2 | 2011 |
| Oberlin | MICHIGAN | 2 | 1994 |
| Sand Lake | MICHIGAN | 2 | 1996 |
| Gilman | WISCONSIN | 2 | 2004 |
| Crandon | WISCONSIN | 2 | 2018 |
| Marenisco | MICHIGAN | 1 | 1994 |
| Ned Lake | MICHIGAN | 1 | 2014 |
| Herman | MICHIGAN | 1 | 2022 |
| Crystal Fls | MICHIGAN | 1 | 2009 |
| Gibbs City | MICHIGAN | 1 | 2013 |
| Maple Grove | MICHIGAN | 1 | 2017 |
| Ishpeming | MICHIGAN | 1 | 2021 |
| Wilson | MICHIGAN | 1 | 2008 |
| Cunard | MICHIGAN | 1 | 1997 |
| Muskallonge | MICHIGAN | 1 | 2013 |
| Gilchrist | MICHIGAN | 1 | 1997 |
| Lake City | MICHIGAN | 1 | 1978 |
| Skegemog Pt | MICHIGAN | 1 | 2023 |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.