Gregersen, F. and Haugen, T.O. and Vollestad, LA. (2008) Contemporary egg size divergence among sympatric grayling demes with common ancestors. Ecology of Freshwater Fish, pp. 110-118
| Species | Development state | Trait | Primary Data | Secondary Data |
| Thymallus thymallus | Larvae | Larvae behaviour | Hatching occurs within the gravel, and yolk sac larvae remain within the gravel until the yolk is resorbed. The larvae then emerge from the gravel, fill their swim bladders with air and, for a period, stay in mid-water shoals. After a few days, the take the position closer to the bottom, and the shoals reduce to small groups or single individuals | Demersal |
| Thymallus thymallus | Spawning conditions | Spawning migration period | Mature fish migrating into streams and rivers after ice break | No data |
| Thymallus thymallus | Spawning conditions | Spawning season | The grayling spawn in spring | ['April', 'May', 'June'] |
| Thymallus thymallus | Spawning conditions | Spawning substrate | During spawning, eggs are deposited a few centimetres below the gravel surface | Lithophils |
| Thymallus thymallus | Spawning conditions | Spawning site preparation | During spawning, eggs are deposited a few centimetres below the gravel surface | Susbtrate chooser |