Select until 14 March
Totals Nijensleek (nacht) 2017 - 2026
| | Species | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 | Totals | Average | Present | Year Maximum | |
| 1. | Canada Goose | 0 | 0 | 1 | 0 | 6 | 0 | 3 | 0 | 3 | 7 | 20 | 2.5 | 0 | 7 (2026) | | | | |
| 2. | Barnacle Goose | 0 | 0 | 0 | 88 | 3 | 0 | 0 | 0 | 2 | 235 | 328 | 41 | 0 | 235 (2026) | | | | |
| 3. | Greylag Goose | 0 | 0 | 2 | 51 | 16 | 0 | 0 | 17 | 18 | 5 | 109 | 14 | 0 | 51 (2020) | | | | |
| 4. | Tundra Bean Goose | 0 | 0 | 4 | 0 | 2 | 2 | 2 | 104 | 85 | 6 | 205 | 26 | 0 | 104 (2024) | | | | |
| 5. | Eurasian White-fronted Goose | 0 | 0 | 0 | 11 | 129 | 12 | 40 | 645 | 1244 | 598 | 2679 | 335 | 0 | 1244 (2025) | | | | |
| 6. | Eurasian / Greenland White-fronted Goose | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 11 | 11 | 1.4 | 0 | 11 (2026) | | | | |
| 7. | Mute Swan | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0.1 | 0 | 1 (2024) | | | | |
| 8. | Bewick's Swan | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 4 | 4 | 0.5 | 0 | 4 (2026) | | | | |
| 9. | Egyptian Goose | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0.1 | 0 | 1 (2020) | | | | |
| 10. | Gadwall | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 0.1 | 0 | 1 (2023) | | | | |
| 11. | Wigeon | 0 | 0 | 0 | 3 | 0 | 1 | 3 | 0 | 1 | 67 | 75 | 9.4 | 0 | 67 (2026) | | | | |
| 12. | American Wigeon | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 3 | 0.4 | 0 | 3 (2026) | | | | |
| 13. | Mallard | 0 | 0 | 0 | 2 | 34 | 1 | 0 | 1 | 18 | 11 | 67 | 8.4 | 0 | 34 (2021) | | | | |
| 14. | Pintail | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 3 | 4 | 0.5 | 0 | 3 (2026) | | | | |
| 15. | Teal | 0 | 0 | 0 | 0 | 1 | 0 | 2 | 0 | 0 | 0 | 3 | 0.4 | 0 | 2 (2023) | | | | |
| 16. | Quail | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0.1 | 0 | 1 (2020) | | | | |
| 17. | Water Rail | 0 | 0 | 1 | 1 | 0 | 2 | 0 | 0 | 0 | 10 | 14 | 1.8 | 0 | 10 (2026) | | | | |
| 18. | Moorhen | 0 | 0 | 2 | 1 | 0 | 2 | 2 | 0 | 1 | 10 | 18 | 2.3 | 0 | 10 (2026) | | | | |
| 19. | Coot | 0 | 0 | 2 | 1 | 4 | 2 | 3 | 1 | 1 | 8 | 22 | 2.8 | 0 | 8 (2026) | | | | |
| 20. | Crane | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 2 | 0.3 | 0 | 2 (2025) | | | | |
| 21. | Little Grebe | 0 | 0 | 1 | 0 | 2 | 0 | 0 | 0 | 1 | 10 | 14 | 1.8 | 1 | 10 (2026) | | | | |
| 22. | Oystercatcher | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 8 | 9 | 1.1 | 0 | 8 (2026) | | | | |
| 23. | Golden Plover | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0.1 | 0 | 1 (2026) | | | | |
| 24. | Little Ringed Plover | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0.1 | 0 | 1 (2021) | | | | |
| 25. | Lapwing | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0.1 | 0 | 1 (2026) | | | | |
| 26. | Whimbrel | 0 | 0 | 0 | 1 | 2 | 1 | 0 | 0 | 0 | 0 | 4 | 0.5 | 0 | 2 (2021) | | | | |
| 27. | Curlew | 0 | 0 | 2 | 0 | 1 | 2 | 1 | 1 | 0 | 0 | 7 | 0.9 | 0 | 2 (2019) | | | | |
| 28. | Common Sandpiper | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0.1 | 0 | 1 (2021) | | | | |
| 29. | Greenshank | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0.1 | 0 | 1 (2019) | | | | |
| 30. | Black-headed Gull | 0 | 0 | 0 | 1 | 4 | 1 | 0 | 0 | 0 | 7 | 13 | 1.6 | 0 | 7 (2026) | | | | |
| 31. | Common Gull | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0.1 | 0 | 1 (2026) | | | | |
| 32. | Cormorant | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 251 | 251 | 31 | 0 | 251 (2026) | | | | |
| 33. | Bittern | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 2 | 0.3 | 0 | 2 (2026) | | | | |
| 34. | Grey Heron | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 4 | 8 | 1 | 0 | 4 (2026) | | | | |
| 35. | Barn Owl | 0 | 0 | 0 | 3 | 1 | 1 | 1 | 1 | 0 | 2 | 9 | 1.1 | 0 | 3 (2020) | | | | |
| 36. | owl sp. | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0.1 | 0 | 1 (2021) | | | | |
| 37. | Eagle Owl | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 2 | 3 | 0.4 | 1 | 2 (2026) | | | | |
| 38. | Tawny Owl | 0 | 0 | 0 | 4 | 2 | 0 | 0 | 0 | 0 | 2 | 8 | 1 | 0 | 4 (2020) | | | | |
| 39. | Song Thrush | 0 | 0 | 0 | 1 | 1 | 4 | 11 | 0 | 0 | 4 | 21 | 2.6 | 0 | 11 (2023) | | | | |
| 40. | Redwing | 0 | 0 | 1 | 71 | 21 | 198 | 33 | 0 | 35 | 16 | 375 | 47 | 0 | 198 (2022) | | | | |
| 41. | Blackbird | 0 | 0 | 0 | 0 | 1 | 12 | 0 | 0 | 0 | 2 | 15 | 1.9 | 0 | 12 (2022) | | | | |
| 42. | Spotted Flycatcher | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 2 | 0.3 | 0 | 1 (2021) | | | | |
| 43. | Robin | 0 | 0 | 0 | 5 | 2 | 1 | 0 | 0 | 0 | 0 | 8 | 1 | 0 | 5 (2020) | | | | |
| 44. | Species unidentified | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 3 | 0.4 | 0 | 1 (2019) | | | | |
| | Species | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 | Totals | Average | Present | Year Maximum | |
| |
Totals |
0 | 0 | 19 | 248 | 237 | 244 | 102 | 772 | 1413 | 1292 | 4327 | 541 | 2 | | |
| |
Observation hours |
| | 68:53 | 53:24 | 84:13 | 71:50 | 107:34 | 38:33 | 51:49 | 141:49 | 618:05 | 77:16 | | | |