Additionally, we measured levels of the lipid hormone prostaglandin F2a (PGF2) across the ovarian cycle, as PGF2 plays an important role in the reproductive physiology of female vertebrates, both at the level of ovarian maturation and behavior [reviewed in 41]. More generally, many studies in teleosts have profiled steroid hormone levels in seasonal breeders [5,9,25,32,35], whereas the hormonal profiles of species that breed year-round are comparatively understudied [44].