Meeting Abstract

56.2  Tuesday, Jan. 5  Life history correlates of cortisol and androgen levels in a parental teleost fish O’CONNOR, Constance M*; BARTHEL, Brandon L; GILMOUR, Kathleen M; PHILIPP, David P; VAN DER KRAAK, Glen; COOKE, Steven J; Carleton University, Ottawa; University of Illinois, Champagne-Urbana; University of Ottawa, Ottawa; University of Illinois, Champagne-Urbana; University of Guelph, Guelph; Carleton University, Ottawa coconno4@connect.carleton.ca

For the past 10 years, researchers have monitored the reproductive ecology of smallmouth bass (Micropterus dolomieu) in an inter-connected lake and river system in eastern Ontario. Each year during the reproductive period, all parental fish are temporarily removed from the nest to determine identity. Scales are obtained to assess age, and fish are measured and monitored throughout the parental care period to assess annual reproductive success. During the summer of 2009, all parental fish (n=184) were subjected to an additional standardized capture-and-restraint protocol, and non-lethally sampled for blood to determine whether cortisol or androgen levels (testosterone and 11-keteotestosterone) are correlated with any life history characteristics. We revealed that the cortisol stress response is higher in fish from the river than from the lake. This likely reflects the difference in predation risk between the two locations, with fish from the river being more vulnerable to predation during parental care than fish from the lake. Furthermore, we found that androgen levels are correlated with a suite of life-history characteristics, including size and age of the parent, prior nesting experience, and the number of offspring in the nest. Collectively, this study contributes to our understanding of the interplay between the endocrine system and life history in wild animals, and represents the first such long-term study on wild fish.