Effects of the synthetic estrogen 17α-ethinylestradiol on Heterandria formosa populations: Does matrotrophy circumvent population collapse?

•A full-life, chronic, single breeding season exposure was used to examine EE2’s estrogenic potential to Heterandria formosa fish populations.•H. formosa populations and population growth rates were significantly reduced after one breeding season of chronic exposure to 5 ng/L EE2.•Analyses of population dynamics showed that the chronic exposure to EE2 caused a significant reduction in the number of males and newborns.•17α-ethinylestradiol exposure resulted in female-biased populations.