Morphofunctional Characteristics of the Ovaries of Pumpkinseed Lepomis gibbosus (Linnaeus, 1758) from the Kuchurgan Reservoir (Cooling Water Body of the Moldavian Regional Power Plant)

Abstract

The results of studies of the reproductive system in sexually mature pumpkinseed Lepomis gibbosus (Linnaeus, 1758) (Centrarchidae) females during spawning in the Kuchurgan Reservoir (liman), the cooling water body of the Moldavian Regional Power Plant, are presented. Asynchronous development of germ cells in the ovary is characteristic of this invasive species. The females spawn three times in May–July, and the relative gonad weight decreases with each generation, so that the gonadоsomatic index before the second and third spawning is sequentially reduced. This is confirmed by the decrease of the weight of eggs and the relative gonad weight during the formation of the second and third egg cell portions within a specific breeding season. Females with severe impairments of gonad development were identified.