Open AccessEvaluation of the reproductive parameters of female neotropical migratory fish from a lotic and lentic environment of a dammed river
Author(s) -
Luiza Mariz Amador de Souza,
Gabriela Gonçalves Theobaldo,
Elizete Rizzo,
José Eduardo dos Santos,
Nilo Bazzoli,
Alessandro Loureiro Paschoalini
Publication year - 2021
Publication title -
tropical zoology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.268
H-Index - 24
eISSN - 1970-9528
pISSN - 0394-6975
DOI - 10.4081/tz.2021.73
Subject(s) - lake ecosystem , river ecosystem , fecundity , biology , ecology , population , biodiversity , fishery , ecosystem , demography , sociology
The fragmentation of watercourses caused by dams is considered to be one of the main threats to aquatic biodiversity worldwide, especially for ichthyofauna. Several studies have shown that the environmental modifications caused by dammed water bodies can change the various reproductive parameters of freshwater fish. Therefore, the present study aims to comparatively analyze the reproductive potential of female Megaleporinus reinhardti, a migratory species, sampled in the lentic environment of the Três Marias Reservoir and the lotic environment of the São Francisco River. Biometric data were obtained from 79 females and the biological indices were subsequently calculated. Additionally, the microscopic analysis of the gonads was performed, and the follicular atresia index was compared. The results of the study show that fish from the lotic environment presented higher gonadal volume, fecundity, and oocyte diameter, and a lower follicular atresia index when compared to fish from the lentic environment. In summary, the data suggest that environmental changes, i.e. from a lotic to lentic environment, caused by river damming, may negatively affect the reproductive process of migratory fish, such as M. reinhardti, and impair the maintenance of the population of this species in lentic environments