| Hydra sp. | | 1991-08-27 | 1991-08-27 | Jarenvannet (Innlandet, Norway) |
| Hydra sp. | | 1989-09-14 | 1989-09-14 | Myravatnet (Vestland, Norway) |
| Hydra sp. | | 1989-09-20 | 1989-09-20 | Sagtjernet (Innlandet, Norway) |
| Hydra sp. | | 1990-10-25 | 1990-10-25 | Moensvatnet (Vestland, Norway) |
| Hydra sp. | | 1989-11-07 | 1989-11-07 | Moensvatnet (Vestland, Norway) |
| Hydra sp. | | 1989-09-27 | 1989-09-27 | Vikerauntjønna (Trøndelag, Norway) |
| Hydra sp. | | 1989-09-14 | 1989-09-14 | Hostadvatnet (Møre og Romsdal, Norway) |
| Hydra sp. | | 1989-10-08 | 1989-10-08 | Hammervatnet (Trøndelag, Norway) |
| Hydra sp. | | 1989-09-20 | 1989-09-20 | Årungen (Akershus, Norway) |
| Hydra sp. | | 1989-09-01 | 1989-09-01 | Kolbjørnviksjøen (Østfold, Norway) |
| Hydra sp. | | 1989-09-14 | 1989-09-14 | Kvitblikkvannet (Nordland, Norway) |
| Hydra sp. | | 1989-09-28 | 1989-09-28 | Husavatnet (Vestland, Norway) |
| Hydra sp. | | 1989-08-28 | 1989-08-28 | Arkavatnet (Rogaland, Norway) |
| Hydra sp. | | 1992-06-12 | 1992-06-12 | Harestuvannet (Akershus, Norway) |
Sustain.no is provided by the Norwegian Centre for Science Education