Billard, R. and Breton, B. (1981) Le cycle reproducteur chez les poissons téléostéens. Cahiers du laboratoire de Montereau, pp. 11-32
| Species | Development state | Trait | Primary Data | Secondary Data |
| Abramis brama | Spawning conditions | Spawning period duration | The duration of the spawning period may depend on the latitude; in the USSR for instance the bream spawning season varies from 58 to 60 days in the North to 16 days in the Volga delta. | 58.0 weeks |
| Thymallus thymallus | Spawning conditions | Spawning season | Spring spawner | ['April', 'May', 'June'] |