Sex differentiation of summer flounder (Paralichthys dentates L.) raised at practical hatchery temperatures


Female summer flounder grow considerably faster than males, and rearing temperature has been shown to influence sex differentiation in related species. The present studies were conducted to examine sex differentiation of post-metamorphic juveniles reared at temperatures conducive for commercial production. In experiments 1 and 2, offspring produced from crosses with meiogynogenetic, sex-reversed males and normal females were raised at 14, 16 or 18°C for ≥300 days or 12°C for 30, 60 or 120 days and then transferred to a male-determining temperature (21°C). In all cases, the fish developed predominantly as phenotypic males (≥74%). In a third experiment, offspring produced from crosses with normal males and females were reared at 15, 17 and 19°C for 111, 227 and 278 days and then transferred to 21°C. Most fish (≥92.1%) developed as phenotypic males irrespective of rearing temperature or length of exposure. Several hypotheses are proposed for these findings and further research is necessary to understand the sex-determining mechanisms in this species before the economic advantages associated with sexually dimorphic growth can be realized.

Publication Date


Journal Title

Aquaculture Research



Digital Object Identifier (DOI)

Scientific Contribution Number


Document Type



© 2013 John Wiley & Sons Ltd