Jansen, W.A. (1996) Plasticity in maturity and fecundity of yellow perch, Perca flavescens (Mitchill): comparisons of stunded and normal-growing populations. Ann. Zool. Fennici, pp. 403-415
| Species | Development state | Trait | Primary Data | Secondary Data |
| Perca flavescens | Female | Age at sexual maturity | The largest immature females from the stunded population attained just over 10% of the weight of the smallest normal females which had reached maturity. At an average age of 2.84 years, stunted females matured exactly 2 years earlier tnah their normal conspecific (4.84 years). Generally, females mature 1 or more years later than male P. fluviatilis or P. flavescens. This can be as early as during the second year of life for P. flavescens. More commonly, though, females are 3 or 4 years old at first maturity, and in some populations it may take on average 5 years to become mature | 10.0 year |
| Perca flavescens | Female | Length at sexual maturity | The smallest stunded female was 8.4 cm long | 8.4 cm |
| Perca flavescens | Female | Weight at sexual maturity | The smallest stunded female weighted 5.52 g | 5.52 kg |
| Perca flavescens | Female | Relative fecundity | Although the weight range of stunted and normal perch did not overlap and values had to be extrapolated for stunded fish, the above relationships between fecundity was used to calculate the fecundity of a 100g 'strandard' perch. For the stunted population this hypothetical fish produced approximatively 5000 more eggs (16556 +/-710) than a corresponding female from the normal population (11327 +/-2245). Data from other studies: 130-232 [For females 190-354 mm in Lake Michigan, US], 130-255 [For females 98-168 in Narrow Lake, CDN], 112-199 [For females 135-257, in Lake Ontario, CDN], 82-184 [For females 174-411 mm, in Patuxent River, US], 85-141 [For females 200-305 mm, in Baptiste Lake, CDN], 132-157 [For female 156-353 mm, in Lake Erie, CDN], | 16556.0 thousand eggs/kg |
| Perca flavescens | Female | Absolute fecundity | Mean fecundity of 28 stunted females 9.8-16.8 cm, was 3992 eggs (range 1910-11812). The corresponding value for 29 normal perch (20.0-30.5 cm) was 22658 eggs (range: 10639-55592). Data from other studies: 10654-157594 [For females 190-354 mm in Lake Michigan, US], 1910-11812 [For females 98-168 in Narrow Lake, CDN], 3035-61465 [For females 135-257, in Lake Ontario, CDN], 5266-75715 [For females 174-411 mm, in Patuxent River, US], 10639-55952 [For females 200-305 mm, in Baptiste Lake, CDN], 12641-135848 [For female 156-353 mm, in Lake Erie, CDN], | 13.3 thousand eggs |
| Perca flavescens | Female | Onset of oogenesis | Rapid gonadal development in September and October | ['September', 'October'] |
| Perca flavescens | Female | Maximum GSI value | For stunted individuals: GSI vary between 22.5 to 30% and for normal females from 12.5-22.5% | 17.5 percent |
| Perca flavescens | Male | Age at sexual maturity | Out of the 483 stunded males analyzed for maturity status, almost all fish had reached maturity by the time they were two years old, and one male reached maturity after the firstgrowing season. The average age at maturity (1.61 years) of stunded males was nerly 1 year less than that of normal males (2.52 years). Males of P. flavescens and P. fluviatilis typically spawn at age 2, although in some populationsof P. fluviatilis almostall fish mature furing their first year of life, and in one reported case most male P. flavescens mature at age 1 | 483.0 years |
| Perca flavescens | Male | Length at sexual maturity | The smallest fish of the stunted males was 5.9 cm. The smallest mature male from the normal population measured 10.0 cm | 5.9 cm |
| Perca flavescens | Male | Weight at sexual maturity | The smallest fish of the stunted males weighted 1.71 g. The smallest mature male from the normal population weighted more than 10 g | 1.71 kg |
| Perca fluviatilis | Female | Length at sexual maturity | Described as female P. fluviatilis to first spawn as smal as 9.3 and 10 cm, the smallest size recorded for this species. | 10.0 cm |
| Perca fluviatilis | Female | Relative fecundity | Values reported in various studies: 50-146 [For females 176-324 mm, in Lake Kinord and Davan, GB], 69-216 [For females 115-210 mm, in Lake Agios Vasilios, GR], 52-188 [For females 98-278 mm, in Salpton Ley, GB], 33-141 [For females 145-422, in Lake Pounui, NZ], 91-317 [For females 115-330 mm, in lake Klicava, CSSR] | 98.0 thousand eggs/kg |
| Perca fluviatilis | Female | Absolute fecundity | Values reported in various studies: 9277-74124 [For females 176-324 mm, in Lake Kinord and Davan, GB], 2080-24488 [For females 115-210 mm, in Lake Agios Vasilios, GR], 1000-30500 [For females 98-278 mm, in Salpton Ley, GB], 2657-63858 [For females 145-422, in Lake Pounui, NZ], 6710-144000 [For females 115-330 mm, in lake Klicava, CSSR] | 41700.5 thousand eggs |
| Perca fluviatilis | Male | Length at sexual maturity | For male, the size at maturity is 6.3 cm, or possibly smaller. Also reported the smallest maturing males to measure "about 55 mm" in the fall. | 6.3 cm |