Site: Olen
| Species | Scientific name | 2018 | 2020 | 2021 | 2022 | 2024 |
|---|---|---|---|---|---|---|
| Blue Tit | Cyanistes caeruleus | 1 | 1 | 1 | 1 | |
| Eurasian Bullfinch | Pyrrhula pyrrhula | 1 | 1 | 1 | 1 | |
| Willow Tit | Poecile montanus | 1 | 1 | 1 | 1 | |
| Great Tit | Parus major | 1 | 1 | 1 | 1 | 1 |
| Marsh Tit | Poecile palustris | 1 | 1 | |||
| Nuthatch | Sitta europaea | 1 | 1 | 1 | 1 | |
| Coal Tit | Periparus ater | 1 | 1 | 1 | 1 |
