Effect of temperature and food availability on reproductive investment of first-time spawning male Atlantic cod, Gadus morhua

• Published in: ICES Journal of Marine Science
• Main Authors: Yoneda, Michio, Wright, Peter J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press (OUP) 2005
• Subjects: atlantic cod; Gadus morhua
• Online Access: http://dx.doi.org/10.1016/j.icesjms.2005.04.018; http://academic.oup.com/icesjms/article-pdf/62/7/1387/29123938/62-7-1387.pdf

Abstract This study demonstrates how temperature and food availability affect growth, maturation, and sperm production in first-time spawning male cod in captivity. Cod, prior to the onset of maturation, were held under four different varying temperature and feeding regimes between November 2002 and March 2003. Lower food availability resulted in poor growth and body condition. Decreasing temperature partly led to slower growth in fish that matured during the experiment. Low temperature resulted in lesser proportions of mature fish relative to the higher temperature treatments. Higher temperature and food availability resulted in higher sperm production (testicular weight and gonadosomatic index). Our findings suggest that variation in food availability would mainly affect the growth and condition and the level of gamete production whilst variation in temperature would affect the proportion of males that mature. These results are contrasted with similar data for female cod.