Heibo, E. and Vollestad, L.A. (2002) Life-history variation in perch (Perca fluviatilis L.) in five neighbouring Norwegian lakes. Ecology of Freshwater Fish, pp. 270-280
| Species | Development state | Trait | Primary Data | Secondary Data |
| Perca fluviatilis | Male | Age at sexual maturity | All males mature at an age of 2 years, and 54.5 were mature at 1 year old | 2.0 years |