Species · BCR 12 · BBS 2025 Release · 1966–2024
Common Grackle In Boreal Hardwood Transition
Common Grackle in Boreal Hardwood Transition has edged down: down 19% on the route-weighted index since 1968.
-19%Since 1968
126Routes In Region
58Years
Notable Signals
No notable trend signals for Common Grackle in Boreal Hardwood Transition. See the full index history below.
Forecast
If the recent trend holds, Common Grackle in Boreal Hardwood Transition is projected to fall about 19% by 2029 — from 5.7 in 2024 to a central estimate of 4.7 (95% range 0.94–8.4). A 5-year backtest shows a typical error of ±20.9%, with 100% of held-out values landing inside the 95% band.
-19%Change by 2029
4.7Projected 2029 index
0.94–8.495% range
±20.9%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 4.9 | 1.2 | 8.7 |
| 2026 | 4.9 | 1.2 | 8.6 |
| 2027 | 4.8 | 1.1 | 8.5 |
| 2028 | 4.7 | 1.0 | 8.4 |
| 2029 | 4.7 | 0.94 | 8.4 |
Routes In Boreal Hardwood Transition
| Brocky Lake | MICHIGAN | 53 | 2024 |
| Walloon Lake 2 | MICHIGAN | 51 | 2024 |
| Skeels | MICHIGAN | 47 | 2015 |
| Traverse Cty | MICHIGAN | 36 | 1992 |
| Marenisco | MICHIGAN | 30 | 2019 |
| Mayfield | MICHIGAN | 25 | 2022 |
| Shanagolden | WISCONSIN | 21 | 2024 |
| Frederic | MICHIGAN | 20 | 2003 |
| Pickford | MICHIGAN | 19 | 2024 |
| Riggsville | MICHIGAN | 19 | 2019 |
| Cedar Run | MICHIGAN | 17 | 1999 |
| Crystal Fls | MICHIGAN | 16 | 2024 |
| Phillips | WISCONSIN | 16 | 2024 |
| Pleasant Valley 2 | MICHIGAN | 14 | 2024 |
| Union Twp | WISCONSIN | 14 | 2024 |
| Irons | MICHIGAN | 13 | 1989 |
| Little Fork | MINNESOTA | 13 | 2024 |
| Bear Lake | MICHIGAN | 12 | 2024 |
| Skegemog Pt | MICHIGAN | 12 | 2024 |
| Walloon Lake | MICHIGAN | 12 | 2004 |
| Brush Creek | MICHIGAN | 11 | 2016 |
| Cathro | MICHIGAN | 11 | 2016 |
| Nebish | MINNESOTA | 11 | 2022 |
| Rib Lake | WISCONSIN | 11 | 2024 |
| Irma | WISCONSIN | 11 | 2024 |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.